Pile refusal criteria shall be as per API RP 2A and repezted below for
clarity.
300 blows / 0.3m for 5 consecutive 0.3m (for contineous driving)
800 blows / 0.3m
800 blows / 0.152m (setup case)

The most stringent of the above shall be applied to determine the pile refusal.

Note:
Many times, the hammer manufacturer recommendation will be final.

Failure modes such as general Collapse of the Chord, Local Failure of the Chord, Unzipping or Progress Weld Failure, Material Problems etc; might occur in a tubular connections subjected to axial and bending loads. Failure of a tubular connection may happen due to any one of the failure modes or combination of them. Failure due to material and…[Read more]

Subsea wellheads are machined, forged steel housing welded to the surface casing of a subsea well to which a BOP or a subsea tree may
be connected for controlling the well and containing well pressures during drilling and production operations.