Abstract: A filter element includes unit members and spacers interposed one each between adjacent ones of the unit members. Each unit member includes a supporting plate having a pair of planar porous membranes joined to the opposite surfaces thereof and also having an opening for insertion of a spacer and removal of a cleaned fluid. The opening has an inner peripheral surface and a stepped part. Each spacer having an outer peripheral part and a stepped part. The stepped part of the opening of one unit member and the outer peripheral part of one spacer define a first axial seal part therebetween, and the inner peripheral surface of the opening of another unit member and the stepped part of the one spacer define a second axial seal part therebetween. The unit members and spacers are interconnected by tightly joining the supporting plates and the spacers at the first and second axial seal parts.

Abstract: A ball valve includes a valve casing accommodating therein an upstream ball seat and a downstream ball seat and defining a cavity between the two ball seats, a ball provided with a through hole, accommodated in the cavity and brought into sealing contact with the two ball seats at the outer periphery thereof, a valve stem having one end thereof fixed to the ball, a valve handle fixed to the other end of the valve stem, a check valve accommodated in the through hole of the ball and biased toward the upstream side, a path formed on the ball and, when the ball valve is closed, causing the downstream side and the cavity to communicate with each other, and a connection port formed on the valve casing so as to communicate with the cavity and having a free end thereof connected to one end of a nipple having the other end thereof covered with a cap. The ball opens and closes the ball valve through the valve stem by a rotating operation of the valve handle.

Abstract: A ball valve with a built-in check valve includes a valve casing having a passageway for a fluid, a ball having a through hole formed therein, also having a valve seat formed inside thereof at a position in the vicinity of one end of the through hole, and rotatably housed in the valve casing so that the through hole is capable of communicating with the passageway, a guide bush provided within the through hole for guiding the check valve, a spiral spring wound on the guide bush for biasing the check valve in the direction of forming a seal contact between the check valve and the valve seat, and rubber or resin damping members attached to the check valve. The check valve is received within the through hole for cutting off the communication between the passageway and the through hole and preventing a counter flow of the fluid, and has a sealing contact portion and a shoulder portion.

Abstract: A pipe joint includes a joint body having an internal thread portion formed in the interior thereof, a bush having formed on the outer periphery thereof an external thread portion helically meshed with the internal thread portion of the joint body, a gasket accommodated within the interior of the joint body, and a retainer having formed on one end thereof on the side of the joint body a flange of increased wall thickness which is pushed toward the joint body by the end face of the external thread portion of the bush. The flange of the retainer may be provided with at least one engaging projection extending radially outwardly from the outer periphery thereof and, in this case, the internal thread portion of the joint body is provided therein with at least one lock portion which is engaged with the at least one engaging projection of the flange.

Abstract: A material for valve seats is molded of a composite resin. The composite resin is composed of polytetrafluoroethylene and a copolymer of tetrafluoroethylene and perfluoroalkylvinylether. The amount of the copolymer falls in the range of from 3% to 30% by weight, preferably in the range of from 10% to 30% by weight, based on the total amount of the composite resin.

Abstract: A material for valve seats is a composite material comprising a base material composed of PTFE and 3 to 30% by weight of PFA based on the total amount of the base material, and 5 to 30% by weight of glass fiber or 5 to 25% by weight of carbon fiber based on the total amount of the composite material. When the glass fiber is used as an additive, 5 to 25% by weight of powdered graphite or 3 to 10% by weight of molybdenum disulfide based on the total amount of the composite material is further added as occasion demands.

Abstract: A spring-return type actuator for valves including a piston cylinder mechanism, a movement conversion-transmission means disposed in the piston cylinder mechanism for converting reciprocation of a piston into a rotary motion of a valve drive shaft, a spring mechanism disposed in series relative to the piston cylinder mechanism, and a plurality of tie rods each including a male member having one end thereof attached to a flange portion of one side wall of the spring mechanism and having an external thread portion, and a female member having one end thereof screwed into a flange portion of the other side wall of the spring mechanism and having an internal thread portion helically meshed with the external thread portion of the male member and having a winglike member attached to the outer periphery thereof for engaging the female member with the outer periphery of the spring box to prevent the female member from rotating, and each tie rod having a length set larger than the free length of a spring when assumed i

Abstract: A butterfly valve includes a body having pipe connecting parts forming two opposite ends thereof and a cylindrical flow path interconnecting the pipe connecting parts, a stem attached rotatably at the central part of the body diametrically across the cylindrical flow path, a lever handle connected non-rotatably to the external leading end of the stem, and a disc formed by joining two substantially circular metallic plates in a mutually opposed manner, coating the entire outer surfaces of the metallic plates with a corrosionproof, resilient material, and boring a stem-insertion hole between the two joined metallic plates in the central diametric position thereof and disposed inside the cylindrical flow path of the body for accommodating the stem non-rotatably within the stem-insertion hole thereof. An externally open groove having a substantially U-shaped cross section is formed in the joint periphery of the two joined metallic plates of the disc.

Abstract: A ball valve with an emergency sealing device has a ball having a through hole rotatably mounted within a valve body; ball seat retainers are positioned between the valve body and the ball; ball seats, made of a heat destructible material are mounted on the ball seat retainers and brought into sealing contact with the ball surface, one each to the ball seat retainers; first sealing rings, made of a heat destructible material for functioning under normal conditions are mounted one each on portions of the ball seat retainers where they contact the valve body; annular projection surfaces are provided on each ball seat retainer on parts of the outer circumferences of the ball seat retainers; second sealing rings, made of a heat resistant, flexible material for functioning in case of emergency, are mounted one each on portions of the annular projection surfaces of the ball seat retainers where they contact the inner circumference of the valve body and have pressing mechanisms engaging them, the diameter of the sec

Abstract: A T-joint having a two-part housing applicable to a pipe contains a member adapted to cut a hole in the pipe when acted upon by an explosive charge to provide a branch conduit from the pipe. The explosive charge is contained in a nut attachable to the housing and is ignited by a percussion cap. The bottom portion of the nut is provided with three concentric recesses, each one smaller than the preceding one. The first recess holds the charge, the second recess holds a breech member for the percussion cap, and the third recess holds an anvil for firing the cap.

Abstract: Special brass with dezincification corrosion resistance, which is essentially composed of copper, zinc, antimony, lead and tin, thereby to remarkably improve the corrosion resistance and the mechanical properties. With at least one addition of iron, aluminium and silicon, the corrosion resistance and mechanical properties are still more improved.