Abstract: A pipe pressure sensor (10) comprises a chamber holder (14) for defining a hollow chamber (28) which is urged toward a pipe (20) to clamp a diaphragm (16) between the pipe and a portion of the chamber holder surrounding a pressure-inlet opening (30) into the chamber. The diaphragm has a round, sensing, protrusion (42) with a sensing tip (46) on an outer end thereof for extending outwardly from one side of the diaphragm to extend through a round hole (44) in the pipe so as to communicate pressure in the pipe to the chamber.

Abstract: A method of constructing a gate valve includes the step of placing a slidable valve gate (46) in a valve cavity (16) between aligned holes (21) of a valve body (10) in a position for closing a fluid passage through the body. Removable mold fixtures (22, 24 and 26) are attached at each opening into the valve body for covering it and thereby preventing liquid material from flowing out of the hole. The valve body (10) and its attachments are heated and a molten resinous material is inserted into the valve cavity so as to surround the aligned holes (21) and to fill spaces between the body (10) and the valve gate (46). The valve body and the resinous material are then allowed to cool so that the resinous material hardens to form a valve liner in which the valve gate moves for opening and closing the fluid passage (80). The mold fixtures are shaped to form flange rings (76, 78) outside the valve-body openings and to form a cavity (84) for packing material (86). A fluoropolymer is used as the resinous material.

Abstract: A turn disc valve (10) includes a rigid, sealed, valve body having first and second, parallel, generally coextensive side-wall rigid plates (20 and 22) with a spacing wall (24) sealed between them to define a flat cavity therebetween. A relatively-resilient, high-density polyethylene, flat liner snugly fits inside said housing cavity and is made up of first and second substantially-flat side liner elements (32 and 34), each of a size and shape for substantially covering opposite interior side walls of the flat body cavity, and a spacer insert element (36) positioned between them. The liner defines a circular valve cavity, with the body side-wall plates and the side liner elements defining a fluid passage through the valve. A circular, flat, gate (16) is positioned snugly in the valve cavity but has freedom of rotation.

Abstract: A knife gate valve (10) comprises an elongated, relatively-flat rigid frame (16) having two rigid side plates (24 and 26) being spaced from one another. A relatively-resilient valve liner (14), forming a valve seat about a liquid flow passage (22) through the frame (16) is insertable into the frame (16) from a first end of the frame so that the liner (14) can be replaced without detaching the gate valve from a fluid system with which it is used. The valve liner (14) has a slot (45) extending into the valve liner from the first end for receiving a gate blade (12). In the preferred embodiment, rigid shields (32) are attached to the frame side plates (24 and 26) about the liquid passage (22) and extend into the liquid passage (22) beyond outer side faces of the liner (14). The liner is made in the form of three inserts which can be positioned within a cavity (31) formed by the shield and frame from the first end.