Operation points: A1 uses 4 M8x22-8.8 hexagon socket screws; A2 uses 4 M8x22-8.8, and before replacement, the connecting rod arm must be fixed with a sling to prevent the arm from falling down after disassembling the motor; A3 uses 4 M8x25-8.8, and the robot arm must be fixed with a sling before replacement. Apply Microlube GL 261 to the teeth, thin and continuous, about 2 g. Check the O-ring and replace it if it is damaged. When installing the motor, tighten diagonally and step by step to the specified torque. When inserting the connector, pay attention to coding and prevent accidental insertion. After replacement, the corresponding axis must be Mastered and the program must be tested in T1 mode.
Common fault three: gear oil leakage and abnormal oil level
The symptoms are oil stains near A1, A2, A3, and A4, high temperature during operation, and metal shavings adhering to the magnetic plug. The reasons include aging of the seal, failure to tighten the plug according to torque, incorrect oil quantity, and incomplete oil discharge caused by installation angle. Replace the gear oil according to the axis during processing. A1 uses Optigear ALR 320, with an initial filling of about 1.90 L; A2 also uses Optigear ALR 320, with an initial filling of about 1.50 L; A3 uses Optigear Synt. ALR 150, with an initial filling of about 0.36 L; A4 uses Optigear Synt. ALR 150, with an initial filling of about 0.08 L; A5 and A6 are within the maintenance range without oil change according to the requirements of this model, but leakage and temperature still need to be checked.
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. Be aware that the oil chamber may be under pressure, and release the pressure before opening the drain plug. The torque of M18x1.5 magnetic plug is about 20 Nm, M10x1 plug is about 7.5 Nm, and A1 union nut is about 45 Nm. After changing the oil, check for leaks and observe abnormalities during T1 operation.

Common Fault 4: Wear and tear of Cable Group A1
The cable group inside the base moves with A1, and long-term operation may result in hose wear, dust accumulation, and friction noise. This model requires 10000 hours of lubrication for cable group A1, using Optitemp RB2 for approximately 200 cm ³. During operation, first remove 2 M4 hex nuts and 5 M5x10-10.9 half round head screws, then remove the cover and brush strip; Use a brush to apply lubricating grease to the outer surface of the hose, the contact surface with the base, and the inside of the cover. 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. For arc welding applications, attention should also be paid to welding spatter and dust, and excessive lubricating grease should not be used to prevent particle adsorption.
Zero point loss and Mastering
The performance is that the teaching point is offset, the program cannot reproduce, and the axis angle display is abnormal. The reasons include replacing the motor, replacing the toothed belt, manually releasing the brake, loss of encoder data, and collision. The Mastering positions of this model are: A1-27 °, A2-90 °, A3 90 °, A4 0 °, A5 0 °, A6 0 °. Priority should be given to using EMD or a dial gauge for standard Mastering. After replacing the A5/A6 toothed belt and A1-A3 motors, it is necessary to re master them. If the release device is used to manually move the motor, the shaft will lose its zero point and must be re Mastered. The accuracy of emergency Mastering is relatively low, and standard methods should be used to recalibrate as soon as possible afterwards.
Plan maintenance and oil change practice
Maintain the core nodes of the table: check the anchor nuts and compression bolts of the foundation after 100 hours; 5000 hours or 1 year inspection shows visible hoses, replace A5/A6 toothed belts; Lubricate cable group A1 after 10000 hours; inspect A1/A2/A3 involute teeth and grease them after 20000 hours or 5 years; Replace A1-A4 gear oil after 20000 hours or 5 years. 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.
When changing the oil, A1 should be filled with Optigear ALR 320 about 1.90 L after draining the oil; A2 about 1.50 L; A3 should be filled with Optigear Synt. ALR 150 about 0.36 L; A4 about 0.08 L. Before draining the oil, the pressure should be released first, and the drainage amount should be measured after draining. The filling amount should be based on the actual drainage amount. The union nut torque of A1 is about 45 Nm, the M18x1.5 plug is about 20 Nm; the M10x1 plug of A3 is about 7.5 Nm; and the M7 blank plug of A4 is about 5 Nm. After changing the oil, check for leaks and observe abnormalities during T1 operation.