Abstract: A coupling is provided for joining segments of plastic pipe. The coupling includes a body portion having an inner bore opening to an enlarged outer bore. A metal stiffener tube having a flange at one end is inserted into the bore of the body until the flange contacts an internal stop. An elastomeric gasket having a substantially rectangular cross-sectional area encircles the stiffener. When the coupling is tightened a corner portion of the gasket initially engages a sloped surface in the enlarged outer bore of the body to initially load the gasket for sealing. A rigid washer encircles the stiffener and contacts the outside end of the gasket. A grip ring, comprising a frustoconical radially outer surface, an inner surface with gripping members, a segmented lateral slot, and a resilient lip around one end, encircles the stiffener so that the lip is in contact with the washer.

Abstract: A preformed coupler for connecting plastic pipe to metal pipe comprises a convoluted tubular metal sleeve, a plastic tube extending part way into the metal sleeve, an annular gasket, and a retention means. The annular gasket, which encircles a portion of the plastic pipe, is compressed against the plastic pipe by the metal sleeve to form a fluid-tight seal. The retention means resists any effort to withdraw the tube from the sleeve. The free end of the metal sleeve can be telescoped over the end of the steel pipe to be joined, then the outer end of the plastic tube can be butt welded to the plastic pipe to be connected, and then the telescoped end of the sleeve can be welded to the metal pipe.

Abstract: A mechanically packed gasket is supported circularly concentric on the operator shaft of a butterfly valve in a wedged interfit with an inwardly chamfered end of the shaft journal. With gasket pressure of magnitudes greater than line pressure, leakage of gas from the valve passage past the actuator is prevented. At the same time, gasket pressure against the operator shaft prevents leakage to atmosphere of any gas content inadvertently obtaining access to the shaft surface either by leakage into the vane cavity through porosity of the vane or through functional failure of other shaft seals. Located outward of the shaft journal in a leakage path parallel to that of the gasket is a lubricant packing construction enabling in-service maintenance to be performed against the journal in the event line content leakage should be encountered there.