Abstract: The present invention provides a valve for use in a lubrication oil circulation system associated with the compressor of a refrigeration system, which valve has internal operating components which can be removed through a sealable access opening in the wall of the body of the valve, thus allowing the operating components of the valve to be inserted into and removed from the valve body through the access opening. This permits the valve body to be connected to the pipework of the circulation system by welded joints in place of the but joints used hitherto. The invention also provides a lubrication oil circulation system incorporating a valve mechanism of the invention.

Abstract: Valve means to control the flow of charge air through a turbocharger intercooler by-pass, comprising a valve housing defining a passage having an inlet and an outlet and adapted to form at least part of the said by-pass, a valve member movably mounted on the housing to close the passage, resilient means on the housing and urging the valve member into a position wherein the passage is open, actuating means for moving the valve member between open and closed positions and thermostatic means mounted on the valve housing and extending beyond said passage for sensing charge air temperature, said thermostatic means being operatively coupled to the valve actuating means to cause the valve member to close the valve when the sensed temperature reaches a given value.