Abstract: A new and improved drain valve for use with plastic fluid flow components, such as pipes, conduits, fittings, joints and the like is provided. The drain valves include a thermoplastic housing which is directly attached by welding or heat-fusion bonding to a plastic line component or is molded in during the molding step for making the line component. Valving members are assembled to the plastic housing to provide for selective drainage of the plastic line components as desired. The new and improved drain valves permit incorporation of drain valves into plastic conduits and fluid flow systems in a sealed and secure manner substantially in the absence of secondary sealing members.

Abstract: In a pneumatically or hydraulically actuated valve, in particular, a diaphragm valve, that comprises a valve body that can be actuated via a coupling rod (14), the coupling rod (14) is held in the corresponding position for adjusting a minimum flow cross section via an adjustable limit stop. The coupling rod (14) passes through the housing cover (12) of a valve housing (10) and serves as an indicator for the valve position.The coupling rod (14) is guided in a sliding fashion inside a sleeve (16), with said sleeve (16) engaging with a threaded bushing (20) that is connected with the housing cover (12) in a fixed manner via an external thread (18), and with said sleeve being able to be displaced in its axial direction (z) by means of a screw-turning motion. A limit stop part (22) that can be brought into contact with the face side (26) of the sleeve (16) situated opposite the valve body is fixed on the free end of the coupling rod (14).