Abstract: A device for providing a sealed intersection between flow passages within a housing comprises an expansion sleeve with a cylindrical outer surface and an axially tapered inner surface for receiving a frusto-conical inner member of greater average diameter and the expansion sleeve is radially expanded in place after insertion into the installation bore, by the forcible insertion therein of the inner member. No interference occurs between the sleeve and the installation bore until after the sleeve is in place in the bore. The outer surface of the sleeve is reduced or not as many be desired to provide fluid communication among the flow passages. Two embodiments differ in that one seals between axially separated ports while the other seals between angularly separated ports.

Abstract: A pressure relief valve comprises a poppet member that is biased toward and sealingly engages a slidable tubular valve seat having unrestrained axial rotation and a central relief flow passage. When the system pressure reaches a threshold pressure the valve seat and poppet are both axially displaced such that at the moment that the poppet is unseated from the valve seat, the valve seat is in motion. The motion of the valve seat when the poppet is unseating or reseating allows the valve seat to comply with any eccentricities of the poppet to achieve uniform seat stresses and low leakage rates as well as acceptable flow rates and low hysteresis.