Structure & Boom Procedures

This page lists 79 maintenance procedures for structure & boom, drawn from HIT Srl's internal procedure library extracted from manufacturer service manuals.

HIT Srl supplies structural and boom spare parts for this class of machine.

General guidance only — always follow the operation and maintenance manual for your specific machine.

Mast

• What is the correct sequence to remove the mast?

  1. Remove the fork carriage.
  2. Put the machine in service position.
  3. Depressurize the hydraulic system.
  4. Connect lifting equipment to the lifting lugs on the mast in a secure manner.
  5. Undo the mast lighting connector and release the mast lighting cable.
  6. Mark up and undo other electrical connectors if there are any.
  7. Put a collection vessel under the mast to collect any spilled oil.
  8. Mark and undo the hydraulic connections for the lift cylinders, plugging all connections at once to protect the hydraulic system from contamination.
  9. Secure the tilt cylinder to an overhead crane and release it from the mast: remove the two screws and the lock plate for the shaft, remove the cylinder shaft (using a slide hammer if necessary), and repeat for the other cylinder.
  10. Undo the mast from the machine by undoing the screw and removing the shafts which fix the mast to the frame, using two M24 screws in the tapped holes as a puller.
  11. Lift the mast away and lay it on the ground.
  12. Undo the lifting equipment.

  Notes:

  • Read the safety instructions for oil before working.
  • The mast can swing out when it is released from the machine; this can cause personal injury.

• What is the correct sequence to install the mast?

  1. Put the machine in service position.
  2. Depressurize the hydraulic system.
  3. Connect lifting equipment to the lifting lugs on the mast in a secure manner.
  4. Lift the mast into place.
  5. Install the shafts and fix them with screws.
  6. Grease the mast anchorage.
  7. Connect the tilt cylinders to the mast: install the cylinder shaft, checking that the bearing in the cylinder anchorage on the mast is correctly aligned before installing the shaft; rotate the shaft to find the correct position for the lock plate; mount the lock plate and secure it with the two screws; repeat for the other cylinder.
  8. Grease the cylinder anchorages.
  9. Connect the hydraulic hoses to the lift cylinders according to the marking, checking that the O-rings are intact and fitted correctly.
  10. Fix the mast lighting cable and join the mast lighting connector together.
  11. Undo the lifting equipment.
  12. Turn the main switch on and start the engine.
  13. Check that the hydraulic connections seal correctly.
  14. Extract air from the lift cylinders (applies to the duplex freelift mast alternative on smaller machines in the range): lift the carriage about 0.5 m; connect a hose to the air vent valve with the other end in a vessel; open the valve and let the oil flow until it runs free of air bubbles.
  15. Check the mast functions, adjusting the tilt cylinders as necessary.
  16. Check the oil level in the hydraulic oil tank with all hydraulic pistons fully retracted, topping up as necessary.

  Notes:

  • Read the safety instructions for oil before working.
  • Risk of crushing while the trolley lowers.

• What is the correct sequence to repair flaking or pitting on the outer and inner mast beam flanges?

  Applies only if the beam flange surfaces have started breaking up in small flakes.

  1. Put the machine in service position.
  2. Remove the fork carriage from the mast.
  3. Remove the mast.
  4. Divide the inner and outer mast.
  5. Remove the mast wheels from the inner mast.
  6. Clean the outer and inner mast.
  7. Grind the affected surfaces smooth and bright with a belt grinder, starting with grain 36-40 and finishing with grain 60-80, with grinding scratches running along the beam direction; check the internal width between front and rear flange, and if it exceeds 187 mm for a 185 mm beam or 247 mm for a 245 mm beam, stop and contact the mast manufacturer.
  8. Fit the mast wheels to the inner mast.
  9. Apply a thin layer of grease to the running surfaces on the outer mast and install the inner mast into the outer mast.
  10. Apply a thin layer of grease to the running surfaces on the inner mast and install the mast onto the machine.
  11. Install the fork carriage into the mast.
  12. Lift and lower the mast to check its function: take a load of 6 tonnes (185 mm beam) or 8 tonnes (245 mm beam) at the stipulated centre of gravity and run up and down 20 times; take a load of 10 tonnes (185 mm beam) or 12 tonnes (245 mm beam) at the stipulated centre of gravity and run up and down 20 times; take the maximum load at the stipulated centre of gravity and run up and down 20 times.
  13. Check that the running surfaces look normal; if not, contact the mast manufacturer.

  Note: Read the safety instructions for oil before working.

• What is the correct sequence to adjust the play for the inner mast on masts with slide plates?

  Applies to masts with slide plates; a different procedure applies to masts with support rollers, described separately.

  1. Remove the fork carriage.
  2. Divide the mast, either installed on the machine or after removing the mast and dividing it on the ground (on a duplex standard mast: undo the cables, chains and hoses necessary for dividing the mast, loosen the circlip attaching the lift cylinders to the inner mast, connect lifting equipment to the inner mast, lift the inner mast away from the outer mast, and place it on the ground in a secure manner).
  3. Check the mast wheels and replace as necessary.
  4. Use a Vernier calliper to measure the internal width of the outer mast (dimensions A and B).
  5. Use a Vernier calliper to measure the external width of the slide plates (dimensions C and D).
  6. Adjust the play: if A and B are equal, adjust D to be equal to or at most 0.5 mm less than B, then adjust C to be equal to or at most 0.5 mm less than D; if A is larger than B, adjust D to be equal to or at most 0.5 mm less than B, then adjust C to be equal to or at most 0.5 mm less than D; if A is less than B, adjust D to be equal to or at most 0.5 mm less than B, then adjust C to be equal to or at most 0.5 mm less than A.
  7. Apply a thin layer of sliding grease to the internal sliding surfaces of the outer mast.
  8. Lift the inner mast and slide the inner and outer mast together.

• What is the correct sequence to adjust the play between the upper support in the outer mast and the inner mast, on masts with support rollers?

  1. Apply a thin layer of sliding grease to the external sliding surfaces of the inner mast.
  2. Lower the inner mast to the bottom position.
  3. Raise the inner mast about 200 mm.
  4. Adjust the upper support to touch the outside of the inner mast, or to give a play of at most 0.5 mm, using an appropriate number of shims at the rear and front end to give alignment along the whole width of the wear pad.
  5. Lift the inner mast to the top position and check that the wear pads do not touch too hard along the beam.

• What is the correct sequence to adjust the play between the fork carriage and the inner mast?

  A smaller adjustment of this play can be performed without removing the fork carriage.

  1. Remove the fork carriage.
  2. Check the mast wheels in the fork carriage and replace as necessary.
  3. Use a Vernier calliper to measure the internal width of the inner mast (dimensions A and B).
  4. Use a Vernier calliper to measure the external width of the slide plates or support rollers of the fork carriage (dimensions C and D).
  5. Adjust the play by loosening the screw and adding or removing shim plates: if A and B are equal, adjust C and D to be equal to or at most 0.5 mm more than A; if A is larger than B, adjust C to be equal to or at most 0.5 mm more than A and adjust D to be equal to or at most 0.5 mm more than B; if A is less than B, adjust C to be equal to or at most 0.5 mm more than A and adjust D to be equal to or at most 0.5 mm less than B.
  6. Apply a thin layer of sliding grease to the internal sliding surfaces of the inner mast.
  7. Install the fork carriage.
  8. Lift the fork carriage to the top position and check that the wear pads do not touch too hard along the beam.

• What is the correct sequence to replace the chain wheels?

  1. Put the machine in service position.
  2. Raise the mast.
  3. Put a support under the fork carriage and lower the mast again, so the chains and hoses are slackened.
  4. Connect lifting equipment to the chain in a secure manner, undo the chain anchorage from the chain tensioner, and lay the chain down.
  5. Remove the hose guide that prevents the hoses from becoming derailed.
  6. Lift the hose off the hose wheel.
  7. Undo the circlip and remove the hose wheel.
  8. Undo the set screw that locks the shaft.
  9. Pull the shaft out and remove the sprocket (the sprocket will fall when the shaft is loosened).
  10. Install a new sprocket, lubricate the shaft with sliding grease, and re-install the shaft.
  11. Lock the shaft with the set screw.
  12. Install the hose wheel.
  13. Install the circlip.
  14. Grease the sprocket.
  15. Put the hoses back and install the hose guide.

• What is the correct sequence to replace the chain wheels on a freelift mast?

  1. Put the machine in service position.
  2. Raise the mast.
  3. Put a support under the fork carriage and lower the mast again, so the chains and hoses are slackened.
  4. Connect lifting equipment to the chain in a secure manner, undo the chain anchorage from the chain tensioner, and lay the chain down.
  5. Undo the set screw that locks the shaft.
  6. Pull the shaft out and remove the sprocket (the sprocket will fall when the shaft is loosened).
  7. Install a new sprocket, lubricate the shaft with sliding grease, and re-install the shaft.
  8. Lock the shaft with the set screw.
  9. Grease the sprocket.
  10. Re-install the chain.

• What is the correct sequence to replace the hose wheels?

  1. Put the machine in service position.
  2. Raise the mast.
  3. Put a support under the fork carriage and lower the mast again, so the chains and hoses are slackened.
  4. Remove the hose guide that prevents the hoses from becoming derailed.
  5. Lift the hose off the hose wheel.
  6. Undo the circlip and remove the hose wheel, lubricating the shaft with sliding grease.
  7. Install a new hose wheel.
  8. Install a circlip.
  9. Put the hoses back and install the hose guide.

• What is the correct sequence to replace the hose wheels on a triplex freelift mast?

  1. Put the machine in service position.
  2. Raise the mast.
  3. Put a support under the fork carriage and lower the mast again, so the chains and hoses are slackened.
  4. Undo the screw, pull out the shaft, and remove the hose wheel, lubricating the shaft with sliding grease.
  5. Install a new hose wheel.
  6. Re-install the shaft and lock it with the screw.

• What is the correct sequence to check the mast suspension?

  1. Put the machine in service position.
  2. Visually check that the frame's mounting points and welding seams are intact.
  3. Check that the mast's mounting points and welding seams are intact, both inside and outside.

• What is the correct sequence to check the mast suspension bearings for wear?

  1. Raise and secure the trolley.
  2. Put the machine in service position.
  3. Visually check that the frame's and mast's mounting points and welding seams are intact, both inside and outside.
  4. Make a marking on the mast.
  5. Remove the load from the mast mountings in an appropriate manner.
  6. Make a new marking on the mast and measure the distance between the markings; it should be a maximum of 1 mm.
  7. If the difference is greater, the bearings in the mast mountings must be replaced.

  Note: Never work under a trolley that is not secured, due to risk of crushing.

• What is the correct sequence to check the mast's slide plates?

  Do not use adjustment shims that are too thick, since inadequate clearance increases wear on the slide plates.

  1. Put the machine in service position.
  2. Check that the slide surfaces in the mast and trolley have a normal appearance without damage or unevenness.
  3. Check the clearance in the mast and between the trolley and mast.
  4. If a noticeable clearance of at least 2 mm arises, reduce it using adjustment shims; if less than 5 mm of wear limit remains on the slide plates, replace them.

• What is the correct sequence to check the lifting chains for wear?

  The check is performed without a load on the side lift attachment; the chains must be thoroughly cleaned over their entire length first.

  1. Measure the length of the 25 links that travel over the chain wheel first (and most often) during lifting, where extension is greatest.
  2. Compare the measurement with the maximum allowed for the chain's pitch; if the extension exceeds 3%, replace the chains.

• What is the correct sequence to check and adjust the lifting chains' tension?

  If the chain is slack when the carriage is in its lowest position, the chain must be tightened.

  1. Check that the pins for the outer washers are securely fastened.
  2. Check that the washers are free of visible cracks.
  3. Check that the chain is free from mechanical damage and rust.
  4. Check that the chain bends easily over the pulley without jamming.
  5. Place the machine on a level surface with the mast vertical (0° tilt).
  6. Lower the carriage to the bottom position.
  7. Check that there is 10-20 mm of space between the carriage and the mast at the inspection hole, adjusting by tensioning or loosening the chains equally on the adjustment nut if needed.
  8. Adjust the chains so the carriage is lifted evenly: loosen the locking washers and remove the lower nut, lift the chain tightener out of the carriage and remove the old locking washer, then reinstall with a new locking washer, chain tightener, locking washer and lower nut, repeating on the other side.
  9. Adjust the nuts on each side to balance the carriage so the distance between carriage and mast is 10-20 mm, then tighten the nuts.
  10. Test lift and check that the lifting chain stretches equally on each side so the carriage is balanced, repeating adjustments as needed.
  11. Once the chains are aligned, lock the nuts with new locking washers.
  12. Lubricate the chains after the inspection is complete.

• What is the correct sequence to check the mast position sensor?

  1. Put the machine in service position.
  2. Wipe the sensor clean with a rag.
  3. Check that it is secured properly.
  4. Check that the distance between the sensor and the inner mast, when directly opposite it, is 10±1 mm.

Boom Sections & pads

• What safety precautions apply before servicing a telescopic arm?

  1. Before starting inspection, make sure no one starts the machine.
  2. Make sure the machine is stable and braked.
  3. Never perform maintenance on the telescopic arm and equipment when the machine is moving.

• How is wear on the fixed arm's side, upper and lower sliding blocks checked and adjusted?

  Performed every 500 hours; the source states a maximum acceptable tolerance of 3 mm on each side for this specific check, distinct from the 2 mm play-check tolerance described elsewhere for sliding block play.

  Periodicity: every 500 hours

  1. Check the side, upper and lower sliding blocks of the fixed arm for wear.
  2. If the tolerance exceeds 3 mm on each side, loosen the nut (1).
  3. Adjust by means of the screw (2).
  4. Tighten the nut (1).

  Note: If the value cannot be achieved by adjustment, replace the sliding blocks.

• What is the correct sequence to replace the fixed arm's sliding blocks?

  Periodicity: every 1500 work hours

  1. Rest the arm with spreader on a container, without raising the load.
  2. Loosen the screws (6) and (1), removing the sliding block support (3).
  3. Loosen the locknuts (5) and remove the worn sliding blocks.
  4. Before fitting the new sliding block, make sure there is no dirt in the housing that could impair its perfect alignment.
  5. Correctly position the sliding block and tighten the screws (5).

  Confirmed across independent manufacturers’ manuals.

• What is the correct sequence to replace the moving arm's sliding blocks?

  Periodicity: every 1500 work hours

  1. Rest the arm with spreader on a container, without raising the load.
  2. Loosen the screws (1) and (6), removing the sliding block support (3).
  3. Loosen the locknuts (5) and remove the worn sliding blocks.
  4. Before fitting the new sliding block, make sure there is no dirt in the housing that could impair its perfect alignment.
  5. Correctly position the sliding block and tighten the screws (5).
  6. After replacement, grease the sliding blocks, pull out the arm and apply a slight film of grease on the indicated surfaces.

  Note: The wear on side sliding blocks (8) is less than on the upper and lower sliding blocks, but it is nonetheless best to replace these too.

  Confirmed across independent manufacturers’ manuals.

• What is the emergency procedure to lower the boom if it fails to lower normally?

  Used in emergency if the boom, with or without load, fails to lower.

  1. Retract the extension cylinder: connect a hose to drain taps (A) and (B) to drain the oil into a suitable container (or recover it into the oil tank), then open the taps and the pressurised cap (T) of the oil tank on the left side of the vehicle. If the cylinder does not retract due to lack of angle, feed pressurised oil (max 250 bar) through tap (B) into the extension cylinder until it retracts, letting oil drain through tap (A) with the tank's pressurised cap (T) open.
  2. Lower the load (lift cylinders): open tap (S), located inside the frame on the centreline of the front crossmember near the accumulator.

  Notes:

  • Before lowering the boom, retract the extension cylinder first.
  • Before lowering the boom, make sure there is no one underneath it or nearby; carry out the manoeuvre in a free, safe area if possible.
  • Remember to close all taps and fittings again after these operations.
  • All these operations must be performed only by qualified, documented and trained personnel, in maximum safety and cleanliness; switch off the engine and confirm the parking brake is applied.

• What is the emergency procedure to raise the boom and free a load if it fails to lift normally?

  Used in emergency if the boom fails to lift and a load needs to be freed.

  1. Disconnect the hose (V) from tap (S) and cap it.
  2. Connect a hose to tap (S) where the hose (V) was disconnected.
  3. Open tap (S) and feed pressurised oil (max 250 bar) through the connected hose.

  Notes:

  • Before lifting the boom, free the load by rotating the twistlocks.
  • Remember to close all taps and reconnect hose (V) after these operations.
  • Oil must always be collected in a suitable container, never released into the environment.

• What boom operations are checked during the 500-hour Type A preventive maintenance service?

  There are four preventive maintenance cards (A, B, C, D) covering the machine's complete maintenance plan, on a 500-hour frequency, cycling in the order B-A-B-C-B-A-B-C-B-D before repeating. Service times assume normal operating conditions and may vary with type of use, road surface, and environment.

  1. Check for oil leaks from the boom's pipes, fittings and components.
  2. Grease the pins and joints of the cylinders (extension, lift, dumping).
  3. Grease the pins and joints of the boom's rear supports.
  4. Grease the boom's extension slide pads/rollers.
  5. Tighten the telescopic boom's bolted joints.

  Note: Maintenance must be carried out only by qualified, authorised personnel, working in conditions of maximum safety.

• How often should the telescopic arm's sliding blocks be greased?

  Periodicity: every 100 work hours, and every time the sliding blocks are replaced

  1. Grease the sliding blocks on the fixed and moving arm every 100 work hours, and every time these are replaced.

• How often is play checked between the telescopic arm's sliding blocks and the arm surface, and what is the acceptable tolerance?

  Periodicity: every 500 work hours

  1. Every 500 work hours, check the sliding blocks inside the fixed arm and moving arm.
  2. Before checking the play between the sliding blocks and the arm surface, carefully remove all grease and dirt.

  Note: Maximum acceptable tolerance for this play check is 2 mm on each side.

Chassis & frame

• When must the main frame of a container stacker be inspected for the first time?

  Periodicity: first inspection after 1 year; subsequent interval never longer than 1 year

  1. The first inspection of the main frame must be made after the first year of machine operation.
  2. On that occasion, the maximum time interval must be established between two consecutive inspections.
  3. In any case, this time interval cannot be longer than one year.

• What should be checked periodically on the pin couplings connecting a machine's moving parts?

  1. Check tightness of stop plates: make sure the pin retention devices are correctly tightened.
  2. Lubrication: periodically grease all the pins on the machine.
  3. Check the condition of the pins and the plates: periodically check their condition; notify and remedy any faults.

  Note: Before starting inspection, make sure no one can start the machine, unless expressly asked to do so.

• What is the correct paint cycle sequence for the machine body?

  1. Surface sanding.
  2. Degreasing with high-pressure cleaners, mixing hot water with 1-2% detergent or equivalent.
  3. First coat of rust preventer.
  4. Intermediate coat of epoxy-vinyl primer, thickness between 60-70 microns.
  5. Final coat, one hour after the rust preventer flash period or not later than 36/48 hours, of gloss polyurethane enamel applied with cross strokes, thickness between 70-80 microns.

  Notes:

  • Before inspecting the machine, make sure no one starts it up, unless expressly requested to do so.
  • When using paints or solvents, always follow the instructions on the containers.

• What is the correct sequence to touch up a damaged painted surface?

  1. When the surface is degreased and dry, remove all scaling and oxidation until the clean metal becomes visible, using sanding discs and an appropriate honing machine (mechanical brushes where necessary).
  2. Mix the filler and the catalyser in the specified proportions, as shown on the product pack.
  3. Apply the metal filler to the recesses using a spatula or suitable doser extruder.
  4. After the part has dried, sand the filled surfaces using a sanding disc.
  5. After sanding, blow off any remaining dust using compressed air.
  6. Apply the rust preventer, followed by the paint cycle.

• What is the correct sequence to manually translate the cab forward for engine access?

  1. Grip the handle of the locking pin "P" (at the rear of the left-hand cab guide) and lift it until it can be rotated.
  2. After rotating it, rest it on the pin guide "G".
  3. Push the cab forward using the handle(s) "M" on the cab (it is recommended this be done by two people).
  4. Before moving the cab back, reposition pin "P" in the locked position (rotating it), then push the cab back until it automatically engages in the correct travel position.

  Notes:

  • Only translate the cab after applying the parking brake and stopping the engine, unless absolutely necessary and specifically instructed otherwise.
  • Do not allow anyone to stand near the cab while it is being translated.

• Which points should be used to lift a reach stacker, and which must never be used?

  1. Rear lifting eyes: valid lifting point.
  2. Front hook-on eyes: valid lifting point.
  3. Slots/eyelets elsewhere on the machine: must never be used for lifting.

  Notes:

  • Lift the machine only without the boom attached.
  • Use chains and a crane suitable for the lifting task; keep personnel away from the vehicle's swing radius during the operation.

• What frame and structural components are checked during the 500-hour Type A preventive maintenance service?

  There are four preventive maintenance cards (A, B, C, D) covering the machine's complete maintenance plan, on a 500-hour frequency, cycling in the order B-A-B-C-B-A-B-C-B-D before repeating. Service times assume normal operating conditions and may vary with type of use, road surface, and environment.

  1. Check the condition of the frame structure.
  2. Check the condition of the cable drag chain.
  3. Check wear of the electrical cables and hoses on the drag chains.
  4. Check the condition of the cradle framework.
  5. Check the condition of the extending sections' framework.
  6. Check the condition of the boom head framework.

  Note: Maintenance must be carried out only by qualified, authorised personnel, working in conditions of maximum safety.

Hoist Chain

• What checks determine whether a lifting chain must be replaced due to wear?

  Periodicity: Inspect at least every 3 months or 1000 hours of operation, whichever occurs first.

  1. Check chain elongation, measured on a slightly tensioned segment 1/5 to 1/15 of the total chain length; maximum admissible elongation is 2% on the most worn segment.
  2. Check wear of the plate profile where most evident; maximum allowable reduction in height is 2.5% on one side or 4% on both sides, relative to the initial height.
  3. Check wear of the side chain; replace the chain if the pin head is worn more than 25% of its initial length, or the plate thickness is worn more than 20% of its initial thickness.
  4. Before installing a new chain, investigate the cause of the problem.

  Notes:

  • If one chain is found worn, replace both chains immediately.
  • A worn chain, unlike a cable, may not show visible signs of wear or imminent breakage; chain breakage can cause injury and damage.

• What should be checked during a sight inspection of the lifting chains?

  1. Check for abnormal protrusions or outjutting pins.
  2. Check for turned-around pins.
  3. Check for worn surfaces or pin heads.
  4. Check for worn horizontal parts and reduced height of chain links.
  5. Check for narrow (tight) articulated joints.
  6. Check for missing links and pins.
  7. Check chain lubrication.
  8. Check chain tension.

• How is the lifting chain cleaned before lubrication?

  1. If a film forms that prevents new lubricant from penetrating, clean the chain before applying new lubricant.
  2. Use a brush and non-inflammable solvent, a degreasing liquid, or a high-pressure cleaner at a temperature of at least 90°C.

• How is the lifting chain lubricated?

  1. If there are signs of oxidisation or dryness, lubricate the chains.
  2. Apply the lubricant to the chain using a brush, ensuring it saturates the chain and penetrates between the links and pins.

  Notes:

  • Free the chain of the load before lubricating, to facilitate lubricant penetration.
  • Do not lubricate the chain while the machine is moving, to prevent personal injury.
  • Use only the lubricant specified in the scheduled maintenance plan.

• How is the tension of the lifting chains adjusted?

  1. Regulate the chain length at the chain/plate connection using the nut and locknut (the mast connection cannot be adjusted).
  2. To increase chain length, unscrew the nut and tighten the locknut.
  3. To reduce chain length, unscrew the locknut and tighten the nut.
  4. After adjusting, carefully make sure both chains are identically tensioned, then tighten the nut and locknut.

Crack Check

• What is the correct sequence to check the machine's structural welds for cracks?

  Periodicity: According to recommended intervals, calculated for normal handling on a level, smooth surface; the interval should be shortened for other handling or rough surfaces.

  1. Turn off the engine and turn off the system voltage.
  2. Clean every weld carefully before inspection.
  3. Check for damage and cracks in the areas with high stress concentration, checking the whole length of every weld.
  4. When uncertain, test welds with the magnetic particle method to determine if there is a crack and where it is.
  5. Investigate any confirmed cracks further with penetrating fluid.

  Notes:

  • Never use a machine with structural damage to the mast and attachment; there is a fatal danger of dropped load.
  • If a weld shows signs of cracking, take the machine out of operation immediately and contact machine manufacturer support.

• What is the correct sequence for the magnetic particle crack-check method?

  1. Blast the applicable area clean so it is completely free of paint residue.
  2. Test using magnetic particle equipment with alternating current and a contrast colour, using a wet colour checking medium.
  3. If no cracks are detected, approve the applicable area.
  4. If cracks are indicated, investigate the crack further with penetrating fluid.

• What is the correct sequence for the penetrating-fluid crack-check method?

  1. Clean the area with cleaning fluid.
  2. Spray penetrating fluid on the cleaned area and let it dry for 10 minutes.
  3. Wash off the penetrating fluid with cleaning fluid, thoroughly wiping it off with a drying cloth and letting any remaining fluid evaporate.
  4. Spray detection fluid on the area.
  5. Let the sprayed area dry for 1-2 hours.
  6. Visually inspect the area; approve it if there are no signs of linear or point-shaped cracks, and contact the machine manufacturer support if there are.

• Which weld locations must be checked for cracks?

  1. Check the steering axle mounts in the frame and in the steering axle cradle.
  2. Check the attachment lugs on the tilt cylinder, and the tilt cylinder's mounting in the mast and in the frame.
  3. Check the horizontal support beams in the mast and the welds between the horizontal and vertical mast beams.
  4. Check the attachment of the frame beam to the rear section.
  5. Check the drive axle mount in the frame.
  6. Check the mast mount in the frame and the weld between the mast beam and mount tab.
  7. Check the side lift attachment's welding seams.
  8. Check the trolley's welding seams and the wheel pin welds in the trolley, including the inner mast wheel pins.
  9. Check the mounting of the lift cylinders' lower support mount against the mast beam.

• Performing dye-penetrant and magnetic particle testing on welded steel structures for fatigue cracks

  1. For dye-penetrant testing: clean and dry the test surface thoroughly, using chemical solvents, vapour degreasing, or mechanical methods (mechanical cleaning such as grinding, blasting or wire brushing may change the test results).
  2. Apply one of the following penetrant types with the proper procedure: water-soluble penetrant, post-emulsifiable penetrant, or solvent-removable penetrant.
  3. For magnetic particle testing: clean the test surface of loose rust scale and moisture, and clean the painted surfaces at all points of welding rod contact (grinding, brushing or blasting do not affect results in most instances).
  4. Apply a magnetic field to the test material with either a permanent magnet or a yoke.
  5. Photocopy the sketch if available, or make your own sketch or photograph, and indicate on the defect: location, size, extent of defect, position in the toe of the weld, and propagation into the base metal.

  Note: All welded steel structures of the crane must be checked yearly for fatigue cracks, paying special attention to the most critical welded joints. If anything unusual is observed by visual inspection, confirm the observation with a magnetic particle test; an ultrasonic test can also be used to complete a magnetic particle test. A dye-penetrant test can be used where it is impossible to use magnetic particle or ultrasonic testing.

• Checking bolt tightness visually on a quayside container crane

  1. Listen to the sound of a pointed hammer hitting the bolt head; the sound indicates whether the bolt is loose or tight.
  2. Visually check the position between the nut and the connecting part; if the manufacturer's marking-pen alignment marks on critical nuts and connecting parts have shifted, this indicates the bolt is loose.
  3. Visually inspect the paint film on nuts and connecting parts; if the paint film has cracked, the bolt should be inspected further.

  Note: For cyclic loading during operation, bolts may loosen; periodic inspection ensures the bolts remain uniformly loaded. Visual check is the most commonly used inspection method.

• Checking and refastening common structural bolts with a torque spanner on a quayside container crane

  1. Mark the original location with a marking pen on the nut and on the joint surface between the structure and the washer.
  2. Develop an initial tension of 75% of the final tension, then develop the final tension.
  3. Check the nut: if it can be turned, mark it for later refastening or replacement.
  4. Replace the bolt joint if needed.
  5. Repeat the marking, tensioning and checking steps for the other bolt joints.
  6. For a rotating (loose) nut: turn the nut about 30 degrees with a torque spanner to loosen it, then refasten it to its pretightening torque requirement.
  7. After refastening, remove all dirt, clean the bolts, nuts, washers and surrounding joint surface with a proper solvent, and repair any damaged paint per the paint repair process.

  Note: Before inspection, the crane must be stopped and the bolts unloaded from working stress. If needed, remove all dirt and paint from the fasteners; spray a thin layer of oil-based rust remover on the nut and washer, which takes 10-20 minutes to take effect.

• Adjusting a quayside container crane's trolley wheel alignment via the eccentric bearing sleeves

  1. Remove the bolts on the bearing block cover board.
  2. Loosen the half seat to rotate the eccentric sleeve.
  3. Find the peak on the eccentric sleeve (three points).
  4. Lift the wheel until it is 2-5 mm above the rail.
  5. Measure the horizontal deviation.
  6. Fasten the bolts on the eccentric sleeve; if necessary, rotate the eccentric sleeve to the correct angle using a punch or other tool.
  7. Put the trolley down, return it to normal condition, and trial-run to check the effect of the adjustment.

  Note: Before starting any disassembly, locate the original position mark on the eccentric sleeve; if the mark is not there, make one, so there is a definite reference for the direction of sleeve turning and the original position can be recovered if the adjustment makes things worse. When correcting a vertical lean, turn the eccentric sleeve gradually, in 15-30 degree increments, checking the trolley's running condition between turns.

• Inspecting welds and high-strength bolted joints on a mobile harbour crane's main structure

  1. If cracks or flaking paintwork are found around a weld, remove the paint back to bare metal and test the weld using penetrant liquid or another suitable method.
  2. If a surface crack is found, contact the manufacturer's after-sales service to arrange a repair; surface cracks could lead to complete structural failure.
  3. For a high-strength bolted joint, check for slip lines or cracks, identifiable by cracks in the paintwork; if found, contact the manufacturer's after-sales service to arrange a repair.
  4. Systematically check the bolt torque setting of each joint once a year, using a calibrated torque wrench, confirming that the actual torque corresponds to the design value in the torque wrench setting table.
  5. Test the torque setting with one of two methods: either use a torque wrench to measure the torque needed to turn the nut a further 10 degrees, or mark the relative positions of the nut and bolt, loosen the nut by turning it at least 60 degrees, then re-tighten it and check whether applying the required torque returns the nut to its original position.
  6. If even one bolt in a joint is found not tightened to the required torque, check all the other bolts in that joint again.

  Note: A first inspection of the crane structure must be carried out one year after the machine is put into service, and the maximum interval between subsequent inspections must not exceed one year. Do not attempt to repair any damaged structural member without prior approval from the manufacturer.

Paint

• What is the correct paint cycle for the machine body?

  1. Sand the surface.
  2. Degrease with high-pressure cleaners, mixing hot water with 1-2% detergent or equivalent.
  3. Apply a first coat of rust preventer.
  4. Apply an intermediate coat of epoxy-vinyl primer, 60-70 microns thick.
  5. Apply the final coat of gloss polyurethane enamel with cross strokes, one hour after the rust preventer flash period or no later than 36-48 hours, to a thickness of 70-80 microns.

• What is the correct paint cycle for the mast, arm and spreader?

  1. Sand the surface.
  2. Degrease with high-pressure cleaners, mixing hot water with 1-2% detergent or equivalent.
  3. Apply a first coat of rust preventer.
  4. Apply an intermediate coat of epoxy-vinyl primer, 40-50 microns thick.
  5. Apply the final coat of black rustproof enamel, one hour after the rust preventer flash period or no later than 36-48 hours, to a thickness of 80-90 microns, for a total average paint cycle thickness of 120-140 microns.

• What is the correct sequence to touch up damaged paint?

  1. Once the surface is degreased and dry, remove all scaling and oxidation until clean metal is visible, using grain-24 sanding discs and an appropriate honing machine, and mechanical brushes where necessary.
  2. Mix the filler and catalyser in the correct proportions as shown on the product pack.
  3. Apply the metal filler to the recesses using a spatula or suitable doser extruder.
  4. Once dry, sand the filled surfaces using a sanding disc.
  5. After sanding, blow off remaining dust with compressed air.
  6. Apply the rust preventer, followed by the paint cycle.

Hoist Mast

• What is the correct sequence to replace the thrust shoes on the fixed mast?

  1. Lower the equipment to minimum height and switch off the engine.
  2. Loosen the four retention screws on the thrust unit.
  3. Remove the thrust unit and loosen the four screws to separate the support from the shoe.
  4. Replace the shoe and refit the four screws.
  5. Fit the thrust unit and tighten the four screws to secure the unit to the fixed mast.

  Note: Replace the thrust shoes if the distance between the shoe and the contrasting section exceeds 1.5 mm.

• What is the correct sequence to replace the thrust shoes on the telescopic mast?

  1. Slightly lift the equipment bearing plate to gain free access to the thrust unit retention screws, and switch off the engine.
  2. Loosen the four retention screws of the thrust unit.
  3. Remove the thrust unit and loosen the four screws to separate the support from the shoe.
  4. Replace the shoe and tighten the four screws.
  5. Fit the thrust unit and tighten the four screws to secure the unit to the telescopic mast.

  Note: Replace the thrust shoes if the distance between the shoe and the contrasting section exceeds 1.5 mm.

• What is the correct sequence to replace the thrust shoes on the equipment bearing plate?

  1. Fully lower the equipment bearing plate and switch off the engine.
  2. Loosen the four retention screws of the thrust unit.
  3. Remove the thrust unit and loosen the four screws to separate the support from the shoe.
  4. Replace the shoe and tighten the four screws.
  5. Fit the thrust unit and tighten the four screws to secure the unit to the equipment bearing plate.

  Note: Replace the thrust shoes if the distance between the shoe and the contrasting section exceeds 1.5 mm.

Telescope Boom

• What is the correct sequence to check the boom fixtures on the extension boom and fixed boom?

  1. Check all parts for damage or wear.
  2. Check the sliding surfaces and sliding plates especially.

  Note: No service work on the boom or attachment is allowed when the engine is running.

• What is the correct sequence to check the boom's sliding plates for wear?

  The sliding plates sit at the front of the inner surface of the fixed boom and the rear of the outer surface of the extension boom, absorbing both vertical and lateral forces; the fixed boom has six sliding plates and the extension boom has four, each with a grease nipple.

  1. Check that the thickness of the sliding plates is at least 15 mm; if the plates are worn enough that the bolts damage the sliding surface, the boom has to be dismounted for service.
  2. If the sliding plates are thicker than 15 mm and the play between the sliding plate and sliding surface is bigger than approximately 2 mm, fit the sliding plates with more shims.

  Note: No service work on the boom or attachment is allowed when the engine is running.

• What is the correct sequence to check for uneven wear of the boom's sliding plates?

  If the sliding plates are worn on one side, the boom will be exposed to torsional stress, so it is important to check the plates regularly.

  1. Check the sliding plates regularly for uneven wear on one side.
  2. Measure the difference in thickness across each plate; if it exceeds the maximum allowed of 2 mm, dismount the plates and plane or replace them.

Fork Carriage

• What is the correct sequence to remove the fork carriage?

  1. Start the machine and set the mast vertical, then lower the mast (the fork carriage must be placed on a flat surface and secured, since it could otherwise tip over when the machine is reversed away).
  2. Put the machine in service position.
  3. Depressurize the hydraulic system.
  4. Mark and undo the hose connections to the fork carriage, plugging all connections at once to protect the hydraulic system from contamination.
  5. Loosen the lifting chains in the vehicle.
  6. Hang weights on the chain to prevent them from running away over the sprocket when the mast is raised.
  7. Start the machine and raise the mast so that the fork carriage comes loose, then reverse away from the mast or move the fork carriage.

  Note: Read the safety instructions for oil before working.

• What is the correct sequence to install the fork carriage?

  1. Start the machine and set the mast vertical.
  2. Hang weights on the chain to prevent them from running away over the sprocket when the mast is raised.
  3. Raise the mast high enough to leave room for the fork carriage.
  4. Fix the fork carriage on a traversing crane and drive the machine towards the fork carriage, or put the fork carriage in place against the mast.
  5. Lower the mast.
  6. Put the machine in service position.
  7. Depressurize the hydraulic system.
  8. Fix the chains in the fork carriage, installing the shaft and locking it with a split pin.
  9. Tension the chains with the chain tensioners, checking that the chains are tensioned equally.
  10. Measure the ground clearance of the fork carriage, which must be equal on the right and left sides within a tolerance of ±5 mm, adjusting further with the chain tensioner if necessary.
  11. Connect the hydraulic hoses to the fork carriage according to the marking, checking that the O-rings are intact and fitted correctly.
  12. Undo the lifting equipment.
  13. Turn the main switch on and start the engine.
  14. Activate the mast functions and check that the hydraulic connections seal correctly.
  15. Check the oil level in the hydraulic oil tank with all hydraulic pistons fully retracted, topping up as necessary.

  Note: Read the safety instructions for oil before working.

• Replacing a gantry travel wheel on a quayside container crane (32 wheels total, 24 driving and 8 driven)

  1. Jack up the crane with no suspended load, in calm weather.
  2. Lock out the crane's motion for the affected drives by performing the lock-out and tag-out procedure.
  3. Move the trolley to the following position: at maximum outreach when the landside leg is jacked up, or at the parking position when the waterside leg is jacked up.
  4. Position the boom: raise it to the maintenance position when the waterside leg is jacked up, or set it to the operating position when the landside leg is jacked up.
  5. At the jack point, connect a jacking-up support to the small equalizer beam with bolts, and use a hydraulic jack of at least 250 t capacity with at least 500 mm of stroke on this support; the jack's center line should match the rail's center line.
  6. Align the hydraulic jack to the center of the lower equalizer beam so the jacking-up support contacts the lower equalizer beam by bolts; jack up the lower equalizer beam and have a forklift hold the truck whose broken wheel is to be replaced, so there is no load at the truck pin.
  7. Jack up the equalizing beam with a second jack, matching it with the first jack at the jack point, until the clearance between shaft and hole is equal.
  8. Push the shaft out by hand.
  9. Lower the bogie onto the rail slowly, then translate it laterally and move it to the workshop with a fork truck.
  10. Remove the cover and pins of the anti-torque plate, then loosen the bolts of the up-tight plate.
  11. Remove the reducer.
  12. Remove the wheel's end-plate, in the workshop.
  13. Remove the bolts on the bearing block.
  14. Suspend the wheel away from the bogie with the service crane.
  15. Pull the shaft out of the bearing with a bearing puller; first install an additional pipe for the puller in the screw hole in the bearing block.
  16. Install the carrier rod of the puller.
  17. Install the hydraulic jack, matching the face between the shaft end and the jack, then start it up.
  18. Pull out the bearing.
  19. Pull out the bearing by hand.
  20. Pull out the bearing pedestal.
  21. Reassemble the bearing and gantry wheel in the reverse order onto the gantry mechanism and equalizing beam.
  22. Install the hollow shaft of the reducer, then install the end-plate and bolts.
  23. Adjust the bolts per the requirements for the up-tight plate of the reducer, and install the cover for the up-tight plate.
  24. Assemble it onto the equalizer beam to finish the replacement.

  Note: Gantry wheels are part of the gantry mechanism, with 8 wheels per corner (32 in total): 24 are driving wheels and 8 are driven wheels. Before replacement, read the drawings on the gantry wheel structure carefully. The jack capacity used to jack up the lower equalizer beam must be at least four times the wheel load value. The procedure for a driving wheel is the same as for a driven wheel, except for the details concerning the reducer and the up-tight plate.

Main Frame

• How is the applied torque moment of a high-resistance bolted coupling checked?

  1. Measure the required moment using a torque wrench, further turning the nut by 10°; or, after marking the nut and bolt to identify their position, first loosen the nut by turning it at least 60°, then tighten it again, making sure the application of the required moment restores the nut to its original marked position.
  2. If even one bolt in a coupling fails to meet the tightness requirement, check all the bolts of that coupling again.

  Note: Perform a yearly statistical check of the torque wrench settings of the bolts in each coupling.

• What is the correct procedure when cracks or paint flaking appear near a structural weld?

  1. If cracks or paint flaking appear near welds, check the welding using penetrating liquids or a similar method.
  2. If surface cracks are found, contact after-sales service to arrange repairs, since the crack could be a sign of breakage.

• Replacing a trolley travel wheel on a quayside container crane (4 wheels, rope-towed trolley)

  1. Move the trolley to the backreach, at its wheel maintenance position, and locate the jack-up point on the trolley frame.
  2. Lower the spreader to the ground and slacken the main hoist ropes.
  3. Perform the emergency stop to forbid all processes that would affect safety.
  4. Install a 10 t jack under the jacking pads on the transverse centerline of the trolley, parallel to the gantry rail; the gap between the top of the rail and the bottom of the jack point is about 300 mm. Raise the truck 10 mm; a timber block may be needed between the trolley frame and the rail top to prevent the trolley from tilting. The anti-lift plate may be removed from the trolley before jacking up.
  5. Loosen the bolts between the cover and sleeve to disconnect the truck with the defective wheel or shaft; lift the truck with the back-reach overhead bridge crane, transfer it to the electric jib hoist at the back reach, and lower it to the ground.
  6. Disassemble the truck at the workshop: first remove the wheel bearing end covers, then mark the outside surface of the bearing seats (eccentric sleeve) and the truck.
  7. Pull out the first bearing.
  8. Pull out the second bearing.
  9. Remove the old bearing.
  10. Install the prepared bearing and bearing seat on the trolley wheel.
  11. Suspend the new wheel into the shaft to assemble it.
  12. Install the sleeve on the shaft, then install the end cover and through cover.
  13. Lift the new wheel and shaft with the service crane at the back reach, translate them to the ground, and reassemble the pin roll.
  14. Install the check plate and positioning bolts.
  15. Install the bumper and other components, then trial-run the trolley.

  Note: Each trolley wheel is supported by two anti-friction bearings housed inside two eccentric bearing sleeves, both with 1.5 mm of eccentricity. It is recommended that trolley wheel or axle repair work be carried out in a workshop rather than on the crane. If there is noise or splashing metal dust from the wheels while running, stop at once, check, and make an adjustment plan. During the new-QC running-in check window of 150-300 hours, check and adjust the trolley wheel again: at that point built-in stress releases and the trolley frame deforms appreciably. At the end of adjusting, trial-run with an empty load first, and if that goes well, trial-run with the rated load (20-30 t); if anything is wrong during this period, adjust the wheel eccentric sleeve seat by 2-5 degrees until acceptable.

Sideshift Frame

• What is the correct sequence to check the sideshift frame's glide plates?

  1. Remove the cover plate, spacer plate and glide plate.
  2. Measure the glide plate's thickness, which should be at least 25 mm.
  3. Check the glide plate's clearance by measuring the distance between the glide plate and the cover plate's edge, which should be 1 mm, fitting or removing spacer plates until correct.
  4. Fit the cover plate.
  5. Repeat the same steps on the other glide plates.

• What is the correct sequence to check the sideshift frame's lower glide plates?

  1. Place axle stands or similar under the attachment's spreader booms and lower the attachment onto the stands so the sideshift frame's lower glide plates can be accessed.
  2. Turn off the engine and the main electrical power.
  3. Place spacers between the cross beam and the attachment's main boom on both cross beams.
  4. Measure the thickness of the glide plates, which should be at least 15 mm, and check that they are of equal thickness.
  5. Remove the spacer.
  6. Turn on the main electric power and start the engine.
  7. Lift the attachment and remove the stands.

Telescopic Boom

• What is the correct sequence to clean, check and grease the telescopic boom?

  A sensor forming part of the anti-tip system, mounted between the frame and the boom, limits the boom's lifting angle.

  1. Clean, carefully inspect and grease the guides and the adjustment plate of the moving boom section.
  2. Clean, inspect and grease the pins anchoring the boom to the frame.
  3. Clean, inspect and grease the pins fastening the lift cylinders.
  4. Clean, inspect and grease the pins fastening the extension cylinder.
  5. Clean, inspect and grease the boom's slide pads: the front pads after extending the moving boom section, and the rear pads with the moving section retracted.
  6. Check the wear of the slide pads, which must be uniform, with a maximum allowed difference (in any direction) of 2 mm; if this value is exceeded, replace the pads, since torsional stresses could otherwise damage the structure.
  7. Check, clean and, if necessary, adjust the boom's lift limit-switch sensor.

  Note: When injecting grease into the pressure fittings, use a manual pump, never a high-pressure greasing pump.

• What is the correct sequence to check the telescopic boom's structure?

  1. Check the welds and inspect the guides.
  2. Check the mounting of the lift cylinders and the extension cylinder, verifying their bearing seats.
  3. Check that the mounting pins of the cylinders (lift, extension, damping) are secured in their seats.
  4. Check the condition of the bushings and bearings.
  5. Check the tightness of all bolted joints.
  6. Check the integrity of the lift, extension and damping cylinders.
  7. Check the condition and tension of the chain positioned on the side of the boom.
  8. Clean and check the lubrication of the entire structure.

Other Structure & Boom procedures

• What are the two methods for checking that a high-resistance bolted coupling still has the correct applied torque?

  A yearly statistical check of the torque wrench settings of the bolts of high-resistance couplings is recommended, using a calibrated torque wrench.

  1. Method 1: measure the required moment using a torque wrench to further turn the nut by 10°.
  2. Method 2: after marking the nut and bolt to identify their position, loosen the nut by turning it at least 60°, then tighten it again, making sure the application of the required moment restores the nut to its original position.

  Note: If even one bolt in a coupling fails to respond to the tightness prescriptions, all the bolts of the coupling must be checked again.

• What is the correct sequence to replace the lift chains?

  1. Put the machine in service position.
  2. Lower the load unit to the lowest position.
  3. Release the lifting chain from the load unit by removing the pin and shaft from each side of the load unit.
  4. Connect lifting equipment to the chain in a secure manner, undo the chain anchorage from the chain tensioner, and lay the chain down.
  5. Fit a new chain.
  6. Tension the chains with the chain tensioners, checking that the chains are tensioned equally.
  7. Measure the ground clearance of the fork carriage, which must be equal on the right and left sides within a tolerance of ±5 mm, adjusting further with the chain tensioner if necessary.

  Note: The lifting chain is heavy and difficult to handle; risk of crushing. Handle with caution and be very careful when the chain is removed from the sprocket, as carelessness can result in serious personal injury and vehicle damage.

• What is the correct sequence to replace a lift fork?

  1. Put the machine in service position.
  2. Remove the shaft connecting the spreading cylinder to the fork by removing the screw and knocking out the shaft.
  3. Remove the four screws that secure the bracket for the spreading cylinder.
  4. Place a hand truck under the fork for support.
  5. Pull out the fork to the side along the carriage, securing the lift fork so that it does not tip.
  6. Replace the fork.
  7. Fit in reverse order.

• What is the correct sequence to replace the engine hood?

  1. Put the machine in service position.
  2. Open the engine hood, remove the lock pin from the gas strut and pull the strut off the ball joint, then close the engine hood and remove the hood over the air filter.
  3. Remove the screws that hold the ventilation grating over the radiator, and remove the grating.
  4. Attach the engine hood to an overhead crane.
  5. Remove the screws for the engine hood, make sure the engine hood is unlocked, and lift the engine hood off.
  6. Replace the engine hood.
  7. Fit in reverse order.

• How is play between the fixed arm's sliding blocks and the arm surface checked and adjusted?

  Periodicity: Check every 500 hours.

  1. Before checking play, carefully remove all grease and dirt from the sliding blocks.
  2. Check the side, upper, and lower sliding blocks of the fixed arm for wear every 500 hours; maximum acceptable tolerance is 3 mm on each side.
  3. If tolerance is exceeded, loosen the nut, adjust with the screw, then tighten the nut.
  4. If the value still cannot be achieved after adjustment, replace the sliding blocks.

• What is the correct sequence to grease all lubrication points every 1000 hours?

  Periodicity: Every 1000 hours.

  1. Lower and fully run out the boom, and fully run out the spreader (positioning).
  2. Turn off the engine and the main electric power.
  3. Grease all grease points on the machine with lubrication grease, and visually check all greased attachments.
  4. Brush the glide areas on the boom and attachment with white lubrication paste.
  5. Run the boom and spreader (positioning) in and out, and sideshift the attachment fully right and left, a few times without load.

  Note: Wipe off surplus lubrication paste.

• What is the correct sequence to check and adjust the lift boom's glide plates?

  1. Place the boom in the lowest, fully retracted position.
  2. Check wear of the side-mounted glide plates at the leading edge of the lift boom, removing a glide plate and measuring its thickness if needed; thickness should be at least 25 mm.
  3. Check the clearance between the boom and glide plate, which should be 1 mm, adjusting with spacer plates if needed (the inner boom must be centred in the outer boom).
  4. Check the thickness of the lower glide plates at the leading edge, removing and measuring if needed; thickness should be at least 15 mm.
  5. Check the clearance between the boom and stop at the leading/top edge, which may be a maximum of 3 mm, adjusting the glide plates with spacer plates if needed.
  6. Check wear of the lower and side-mounted glide plates at the trailing edge of the lift boom, removing and measuring if needed; thickness should be at least 25 mm.
  7. Check the clearance between the boom and glide plate at the trailing edge, which should be 1 mm, adjusting with spacer plates if needed.
  8. Check the thickness of the upper glide plates at the trailing edge, removing and measuring if needed; thickness should be at least 15 mm.

  Note: If a side-mounted or lower glide plate's thickness falls below 25 mm, it may work loose from its bracket and damage the boom.

• What is the correct sequence to check and adjust the main beam attachment's glide plates?

  1. Park the machine with the attachment as far down as possible and the spreading run in so that 40 cm remain to the 20-foot position.
  2. Turn off the engine and the main electrical power.
  3. Take the strain off the glide plate in question, by lifting the spreader beam at the outside edge or using wedges to change the spreader beam's position on the attachment's main beam.
  4. Remove the attaching bolts for the glide plate's bracket.
  5. Remove the glide plate's guide pin.
  6. Pull out the glide plate with its spacer plate and bracket.
  7. Measure the glide plate's thickness, changing it if needed; thickness should be at least 10 mm.
  8. Place the glide plate in the correct position, checking the clearance between the spreader beam and glide plate (maximum 1 mm with all glide plates mounted), fitting or removing spacer plates until correct.
  9. Fit the glide plate's bracket.
  10. Fit the glide plate's guide pin.
  11. Repeat the same steps on the other glide plates.
  12. Start the machine, check the spreading function, and try lifting a container to check that the spreader beams do not have too much clearance.

  Note: Excessive clearance may result in damage to the spreader beam during load handling.

• What is the correct sequence to check and adjust the extension beam's slide plates?

  1. Park the machine with the attachment as far down as possible and the spreading fully run in.
  2. Turn off the engine and the main electrical power.
  3. Take the strain off the slide plate in question, by lifting the extension beam at the outer edge or using wedges to change the extension beam's position in the attachment's main beam.
  4. Remove the attaching bolts for the slide plate's bracket.
  5. Remove the slide plate's guide pin.
  6. Pull out the slide plate with its spacer plate and bracket.
  7. Measure the slide plate's thickness, changing it if needed; thickness should be at least 10 mm.
  8. Place the slide plate in the correct position, checking the clearance between the extension beam and slide plate (less than 1 mm with all slide plates fitted), using a spacer plate to adjust.
  9. Fit the slide plate's bracket.
  10. Fit the slide plate's guide pin.
  11. Grease the slide surface on the extension beam.
  12. Start the machine, check the spreading function, and try lifting a container to check the extension beams' clearance in the main beam.

• What is the correct sequence for the 500-hour lubrication of the mast and tilt cylinder?

  Periodicity: Every 500 hours.

  1. Start the machine and raise the mast to facilitate access to the lubrication points.
  2. Turn off the engine.
  3. Secure the mast in a way that ensures safety.
  4. Lubricate the chain wheel, mast wheel, slide plates and the slide plates' contact surfaces with grease.
  5. Brush or spray the chains with chain oil, making sure they are well lubricated.
  6. Grease the tilt cylinder axles with grease.

  Note: Unload the mast before lubricating the tilt cylinder.

• What is the correct sequence to check the trolley's slide plates?

  1. Park the machine with the attachment lowered as far down as possible and the spreaders in their narrowest position.
  2. Turn off the engine and turn off the system voltage.
  3. Clean the lower slide plates and measure their thickness, which should be at least 10 mm.
  4. Clean the upper slide plates and measure their thickness, which should be at least 10 mm.
  5. Check the clearance between the side lift attachment and the trolley, adjusting with shims if it exceeds 5 mm.
  6. Check that the slide surface is clean and lubricate the slide surface of the side lift attachment.
  7. Start the machine and side shift the attachment to both end positions, checking that clearance between trolley and attachment is sufficient along the whole attachment with no metallic contact.

• What is the correct sequence to check the tilt cylinder?

  1. Visually check that the frame's mounting points and welding seams are intact.
  2. Check that the tilt fork is securely fastened to the tilt cylinder at the specified torque (136 Nm).
  3. Check that the tilt cylinders are correctly adjusted.
  4. Check that the tilt cylinders are properly aligned, so both cylinders reach their end positions simultaneously.

• Replacing a high-strength bolt in a structural flange connection on a quayside container crane

  1. Ensure the washer is smooth and clean, without oil, dirt or burrs.
  2. Clean the joint surface of the structure and washer, ensuring the surface is smooth.
  3. Clean the bolts and nuts.
  4. Use a new bolt to replace the old one marked for replacement, developing an initial tension of 75% of the final tension immediately; fasten the bolts to be replaced one by one.
  5. Deliberately destroy the old bolts that have been removed, to prevent their reuse.

  Note: Bolts replaced at the same time should be from the same production batch, to ensure the same torque factor. Ensure the replacement bolts are of sufficient quantity, correct strength grade, and correct tightening torque; recalibrate the torque wrench repeatedly before use.

• Assembling the eccentric bearing sleeve on a quayside container crane's trolley wheel

  1. Prepare the eccentric sleeve.
  2. Install the bearing on the wheel.
  3. Install the seal on the end cover.
  4. Install the end cover on the wheel.
  5. Install the wheel on the shaft.
  6. Install the bearing seat on the wheel shaft.
  7. Install the whole wheel shaft on the support, adjust the sleeve, and tighten the bolts to fix it; after adjusting the position of the wheel shaft, tighten the bolts on the cover.

Looking for general maintenance tips and checklists? See Structure & Boom.