Common faults and troubleshooting methods of cold rolling equipment for pipe mills
1. Fast forward and rewind will work, normal feed in will not work:
The friction plate on the electromagnetic clutch is worn out too much. Simply remove it and add one more friction plate.
2. Insufficient working pressure of the rotary box:
Reason for occurrence: 1. There is an overflow valve installed on the end face of the rotary box, and there is a valve core inside the overflow valve. There is a small hole in the middle of the core. The small hole of the cutting core is blocked due to unclean engine oil.
Exclusion method: 1. After removing the heart valve, blow it through with an air pump or mouth
3. The gear pump cannot pump oil:
Causes: 1. The main reason is that the cooling oil has been used for a long time, resulting in an increase in impurities in the oil and rapid wear of the gear pump gears.
Exclusion method: 1. Install a filter screen at the oil inlet of the gear pump.
4. The hydraulic working pressure is normal, but the rotary feeding force is insufficient:
Reason for occurrence: 1. The main reason is that the piston end face and the seven corner plane in the hydraulic pump are worn too much, resulting in insufficient hydraulic sealing.
5. Exclusion method: 1. Replace the hydraulic pump. 2. After the hydraulic pump is turned on, the worn surface is manually ground until it is smooth before being installed into the hydraulic pump. Inspection method: There are leakage holes on the hydraulic pump, and the oil leakage should not be too large.
6. The movement and breakage of the core rod in front and behind can cause the car to be stuck:
Reason for occurrence: 1. The core rod chuck may move back and forth due to wear or human error, resulting in a sudden increase in the amount of pressure and rolling force. Mild cases may cause jamming, while severe cases may cause damage to the rolling mill and other components.
Exclusion method: 1. It should be observed at all times, inspected regularly, and replaced in a timely manner to prevent the core rod from moving and breaking.
7. High head vibration:
There are many defects on the pipe surface caused by jumping rolling of the machine head, resulting in large dimensional deviations and increased wear of deformation tools.
Principle and elimination method: This is due to excessive wear of the sliding plate under the rack, resulting in a large gap between the sliding plate and the angle gauge track. It is necessary to replace the sliding plate again. If the angle gauge track is worn, the copper plate needs to be appropriately thickened. 8. Roll surface adhesion:
Rolling ordinary carbon steel generally does not stick to the rolls, while rolling high alloy steel containing nickel such as lCr18Ni9Ti does not, and stainless steel materials will stick to the rolls.
Exclusion method: 1. Choose appropriate cooling oil. In China, paraffin oil and machine oil are generally used in equal quantities for cooling, and the cooling of pipes and rolling tools is increased. Secondly, the roll hole shape is unreasonable and the opening degree needs to be increased.