Bore well at home gives problem

I am having a problem with my bore well at home.

Its a new bore that we have drilled to 500ft and sent a sub moto inside upto 480ft. We get a min water for house use only. Some times 20min in the morning. The water level is low at my site.

But my problem is, the very 1st pipe that connects to my Submerge moto always gets bulged and burst at the middle of the pipe. What could be the reason. My bore technician also says that he has not come across this issue in his whole experience. This has happened 2 times now in 1 month itself.