Due to the high requirements of the customer, and the plunger is not API standard, the plungers are short, and the plunger surface needs to be grooved.
After the spray welding, because of the temperature and technical reasons, we found that there are some small cracks in the plunger grooves after testing.
Actually, we had met the same problem before, we have been supplying this kind of plunger to Weatherford in America.
We later updated our technology. If making the slug after the heat straightness, and then cold straightness and coarse grinding, finally Ni-p plating and fine grinding, it's will be much better.
