Patent ID: 7134810

Claim:
A yieldable prop comprising: a hollow conduit having a first end and an opposite second end, wherein the hollow conduit can support a predetermined compression load before collapsing; and a yield section comprising: a plate having a major surface; an outer sleeve having a first end and an opposite second end, the first end of the sleeve secured to the major surface of the plate; a pipe having a first end, a second opposite end, and a body between the first end and the second end of the pipe, the first end of the pipe secured to the major surface of the plate within the outer sleeve with outer surface of the pipe spaced from inner surface of the outer sleeve to provide a space between the pipe and the outer sleeve; and an insert in the space, wherein the insert can support a predetermined compression load before collapsing, and the predetermined compression load of the insert is less than the predetermined compression load of the hollow conduit, and wherein the first end of the hollow conduit is slidably received in the space with the insert between the major surface of the plate and the first end of the hollow conduit, and wherein the insert is at least not joined to the first end of the hollow conduit.