KUKA KR 300 R2700-2 C-F maintenance troubleshooting

A5/A6 abnormal after oil change

Performance: A5/A6 abnormal noise, positioning error, insufficient fuel level.

Reason: Incorrect oil discharge and filling angle, incorrect oil distribution.

Processing: Move A4 to+90 ° for oil discharge, 0 ° for lower part, and -90 ° for filling; Add about 1/3 to A5 first, and the remaining to A6. After adding, check if the three magnetic plugs are leaking.

Motor overheating, brake failure, or wear of involute teeth

Performance: High motor temperature, difficult release of brake, A1-A6 motion shaking.

Reason: Load exceeding limit, high ambient temperature, insufficient lubrication of teeth, aging of O-ring, improper installation of motor.

Solution: Check the involute teeth, clean and apply Microlube GL 261, thin and continuous. The O-ring must be replaced if it is damaged. When installing the motor, tighten the screws diagonally and step by step to the specified torque. Before replacing A2/A3, the connecting rod arm or robot arm must be fixed with a crane to prevent the arm from falling down after disassembling the motor. Pay attention to the connecting shaft and compression spring when replacing A4/A5; If there is a back up ring on the old motor shaft, it must be discarded and cannot be reused. A6 replacement requires the dismantling of A4, A5, and the inline hoist, which weighs approximately 100 kg and must be reliably lifted.

Wear of connecting shaft

Performance: Large movement gap, abnormal noise, and positioning drift in A4/A5.

Reason: Tooth wear, insufficient lubrication, and damage to the tooth surface during installation.

Solution: The connecting shafts must be replaced in pairs. Clean the teeth and apply Microlube GL 261 before installation. Ensure that the teeth are correctly engaged and not tilted when installing the inline writer.

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. Zero position: A1-25 °, A2-100 °, A3 100 °, A4 0 °, A5 0 °, A6 0 °. After replacing A4/A5/A6 or inline writer, adapt to MAMES value and re master. The accuracy of emergency Mastering is relatively low, and standard methods should be used to recalibrate as soon as possible afterwards.

Casting plate positive pressure loss

Performance: Pollution inside the arm, entry of dust, accelerated wear of bearings and teeth.

Reason: The gas source contains water and oil, insufficient pressure, and pipeline leakage.

Solution: Check the overpressure inside the arm at 0.03 MPa (0.3 bar) ± 10%. The compressed air should be free of oil and water, in accordance with ISO 8573-1:2010 (7:4:4), with a gas consumption of approximately 0.1 m ³/h and a joint of 6 mm. The wrist thermal load is 10 s/min at 180 ° C. Pressure loss can cause dust and coolant to enter, and it must be repaired in a timely manner.

Connector, cable, and grounding 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 C4 uses X20-X30, X21-X31; KR C5 uses XD20.1... XD20.6-XD30, XD10.1/XD10.2-XD30, XF21-XF31. The cross-sectional area of the grounding conductor is 16 mm ², and the torque of the M8 nut is about 23 Nm. When the cable bending radius is fixed and laid, the motor cable should not be less than 150 mm, and the data cable should not be less than 60 mm. The maximum length is 50 m, and it can be extended up to once. The cable shall not bear tensile force and shall be laid separately from the power line. Do not attach other cables to the cable group, and do not fix them with zip ties or Velcro to avoid restricting movement and causing breakage.

Planned maintenance: Block faults before they occur

The core nodes for maintaining a table are as follows:

After 100 hours: Check the torque of the fastening screws and nuts.

2500 hours or 1 year: lubricate the balance cylinder bearings using LGEP 2, with each lubrication nozzle approximately 10 cm ³, and add oil at the middle position, positive and negative end positions respectively; Check the pressure of the balance cylinder.

10000 hours or 5 years: Replace A1, A2, A3, A4, A5/A6 gear oil.

10 years: Replace the balance cylinder.

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.

Key points of oil change practice

A1 (ceiling installation): Drain oil through a quick connector and add oil from below with a union nut torque of 45 Nm. A2: M18x1.5 plug, 20 Nm. A3: M16x1.5 plug, 20 Nm, A3 level. A4: M18x1.5 plug, 40 Nm, A3 level. A5/A6: Drain oil at A4+90 °, drain the lower part at 0 °, add oil at -90 °, add 1/3 to A5 first, the remaining to A6, M18x1.5 screw plug 20 Nm. Check for leaks after each oil change, and observe abnormalities during T1 operation.