KUKA KR CYBERTECH nano-2 maintenance troubleshooting

Reason: seal aging, screw plug not tightened according to torque, incorrect oil quantity, installation angle leading to incomplete oil discharge.

Solution: Replace the gear oil according to the shaft. The recommended oil is Optigear Synt. ALR 150. First filling amount: A1 is about 0.52 L, A2 is about 0.43 L, A3 is about 0.26 L. The replacement cycle is 20000 hours or 5 years. Oil discharge must be carried out at operating temperature and the discharge volume measured. If the discharge volume is less than 70% of the specified amount, it should be rinsed once; If it is less than 50%, rinse twice. The filling amount shall be based on the actual discharge amount. The torque of the M18x1.5 magnetic plug is approximately 20 Nm. Please note that the oil chamber may be under pressure, and release the pressure before opening the drain plug.

Cable group A1 is worn or has abnormal noise

Performance: The hose inside the base is worn, dust accumulates, and there is friction noise during movement.

Reason: Insufficient lubrication, aging of hoses, long-term high-frequency exercise.

Solution: Remove the base cover, inspect the hose, clean it, and apply Optitemp RB2 grease to the outer surface of the hose, the contact surface with the base, and the inner side of the cover, weighing approximately 0.3 kg. If the hose is damaged, the cable assembly must be replaced. After reassembly, wipe off excess grease and move A1 to evenly distribute the grease.

Zero point loss or Mastering abnormality

Performance: teaching point offset, program unable to reproduce, abnormal axis angle display.

Reason: Replacement of motor, manual release of brake, loss of encoder data, collision.

Solution: Prioritize using EMD or a dial gauge for standard Mastering. The Mastering positions for this series are A1-19 °, A2-90 °, A3 90 °, A4 90 °, A5 0 °, A6 0 °. After replacing the motor, toothed belt, and connecting shaft, the Mastering must be redone.

Connector, grounding, and cable layout faults

Performance: The controller reports motor/data line faults, intermittent shutdowns, and abnormal shielding.

Solution: Check the motor cables, data cables, and grounding conductors. KR C5 micro uses XD20.1/XD20.2-XD30, XF21-XF31; The KR C5 S uses XD20.1... XD20.6-XD30, XD10.1/XD10.2-XD30, XF21-XF31. The cross-sectional area of the grounding conductor is 4 mm ² (micro) or 16 mm ² (S), and the torque of the M8 nut is about 15.0 Nm. The bending radius of the cable should not be less than 5xD when laid in a fixed manner, with a maximum length of 25 m (micro) or 50 m (S), and can be extended up to once. The cable shall not bear tensile force and shall be laid separately from the power line.

The brake is damaged after using the release device

Performance: After manually moving the shaft using the release device, there may be abnormal brake noise or a decrease in braking force.

Reason: The release device forcibly overcomes the brake, which may damage the brake.

Handling: The release device is only for emergency rescue use. After use, the relevant motor must be replaced and all axes must be remade. Subsequently, a braking test was conducted, and abnormal observations were observed during the T1 trial run.

Loose or vibrating base bolts

Performance: Robot shaking during operation, abnormal noise from the feet, and poor repeated positioning.

Reason: Insufficient torque of base bolts, cracking of concrete foundation, and failure of chemical anchor bolts.

Solution: Install the base S260 and use 4 M12x40-10.9 hex bolts with a torque of 104 Nm according to Appendix M12 10.9. Tighten after 100 hours and check annually thereafter. The basic concrete grade shall be at least C20/25.

Planned maintenance: Block faults before they occur

The core nodes of the maintenance table for KR CYBERTECH nano-2 are as follows:

100 hours: Check the torque of the anchor nuts and compression bolts of the foundation.

5000 hours or 1 year: Check for visible hose damage; Lubricate cable group A1; replace A5 toothed belt.

20000 hours or 5 years: Replace A1, A2, A3 gear oil.

Before maintenance, the maintenance point must be accessible and any obstructing tools and accessories must be removed. If the oil temperature exceeds 60 ° C for a long time, the maintenance interval should be shortened and KUKA should be consulted. All accessories must use approved products, otherwise it may lead to early wear and tear. For high-frequency, high load, and high beat applications, the maintenance cycle should be appropriately shortened.

Practical replacement of A5 toothed belt

The replacement of A5 toothed belt is a high-frequency operation in nano-2 maintenance. The steps are as follows:

Place the arm in a horizontal position, the wrist axis in zero position, and A6 without tools.

Remove 9 M4x14-10.9 hex screws and lock washers, and take off the belt side cover.

Remove the M4x16-8.8-A2K adjustment screw, and then remove two M3x6-10.9-A2K TORX round head screws.

Loosen the adjustment screw until the toothed belt can be removed from the pulley.

Install a new toothed belt, ensuring that the toothed belt is correctly engaged with the pulley and cannot tilt.

Move the right pulley to the right, pre tighten the toothed belt, and tighten two new M3x6-10.9-A2K TORX round head screws until the pulley cannot move on its own.