Introduction to repairing cracks in large girth gear of rotary kiln

09 Jul,2018 UTC+8 Views:


The large girth gear used in the rotary kiln usually has a diameter of more than 4 meters. The material is generally ZG42CrMo or ZG45. It is a typical large-scale steel casting. The working environment of the rotary kiln girth gear is worried, the force is large, and the working time is long. The large girth gear is prone to cracks and other problems during use. The casting period of large steel castings is long. When cracks occur in the large girth gear, it can be repaired first to reduce the outage time of the rotary kiln to create benefits for the company.

girth gear

First, the crack is removed, and the welding groove is u-shaped. The metal is polished by the groove, and then the PT test is performed to confirm that the cracks are all cleaned, and the oil, embroidery, water, etc. within 100 mm around the welding area are cleaned. clean.

Then, the welded electrode was used for welding, and it was checked whether cracks were generated, and the crack was found immediately after the crack treatment, and the next crack treatment was performed without any defect.

Finally, all welded cracks are subjected to penetration and ultrasonic testing.

The repair of the girth gear crack can only be used temporarily. After the crack is found, a new large girth gear should be purchased in time to ensure the normal operation of the rotary kiln. The Great Wall cast steel specializes in the production of rotary kiln big ring gear, wheel belt, roller, etc. Large cast steel fittings, welcome to consult and purchase.