Patent ID: 11879298
Assignee: REFLEX INSTRUMENTS ASIA PACIFIC PTY LTD
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 0:
1. A drive sub for a drilling assembly, the drive sub comprising
a tubular body configured to receive and releasably engage a tool, the body having an inner face and an outer face;
a castellated edge provided at an operative downhole end of the body, the castellated edge defining a plurality of lugs separated from each other by intervening slots; and
a contour profile provided at least partially along a circumference of the castellated edge, the contour profile traversing the castellated edge substantially from the inner face to the outer face, wherein the contour profile is configured to facilitate flow of drilling fluid and cuttings past the lugs during use,
wherein each of the lugs includes a channel at least partially traversing the contour profile.