Mammoth Top Subs | Bottom Subs can be manufactured to customer specifications & thread requirements.

When rods must be added to increase the depth of drilling, the loosening of the threads are now performed at the bottom end of the saver sub as opposed to the bottom of the top drive (rotary head) which is the most expensive part of the drill string. This means that the connection between the top end of the saver sub and top drive (rotary head) is seldom used, and suffers minimal wear and tear, whereas the lower connection is used in almost all cases displacing the most wear and tear from the rotary head connection to the much lower cost, saver sub which is expendable and does not represent a major investment. The top drive or rotary head component, on the other hand represent a significant capital outlay and considerable downtime when it needs to be replaced.