When the weight of a portion of the drill string below a ram BOP is supported by a tool joint resting on the closed pipe ram or through the use of a special hang-off tool that lands in the wellhead.
Source: API STD 53
When the weight of a portion of the drill string below a ram BOP is supported by a tool joint resting on the closed pipe ram or through the use of a special hang-off tool that lands in the wellhead.
Source: API STD 53