FLOWLINE FLAPPER VALVE

摘要

A check valve assembly has a body having a central cavity intersected by upstream and downstream flow passages. A seat is secured by a threaded engagement in the upstream flow passage. An access bore intersects the cavity and has a support shoulder formed in it. A holder is supported on the support shoulder. A flapper is pivotally secured to the holder and located in the cavity for movement between an open position and a closed position blocking flow through the seat. A straight edge portion in the access bore engages a straight edge portion of the holder to prevent rotation of the holder. A fastener extends through a hole in the support shoulder into engagement with the seat to prevent rotation of the seat.