The present invention provides a porous polymer resin layer that comprises a binder resin with pores having a mean maximum diameter of about 0.5 mm to 1.6 mm; and aerogels dispersed in the binder resin. In particular, the porous polymer resin layer has a density of about 0.5 g/ml to 1.6 g/ml.

A hydraulic tool includes a stator, a rotor, and a removable coating. At least one of the stator and the rotor comprises a resilient material. The removable coating has a thickness selected to compensate for expected swelling of the resilient material or an expected contraction of a clearance between the rotor and the stator based on thermal expansion. The removable coating is disposed on a surface of at least one of the rotor and the stator, and the removable coating is formulated to be removed during operation of the hydraulic tool. A method of operating a hydraulic tool includes passing a fluid through the hydraulic tool during rotation of the rotor within the stator and removing at least a portion of the removable coating responsive to rotation of the rotor within the stator as a volume of the resilient material increases responsive to contact with the fluid passing through the hydraulic fluid.

The invention relates to a reciprocating piston composed of ceramic material for a reciprocating-piston engine with crank drive, wherein the reciprocating piston is rigidly screwed to a piston rod by a screw, wherein between the reciprocating piston and the piston rod there is braced at least one disc composed of metallic material, wherein the screw is composed of a metallic material, wherein the coefficient of thermal expansion .sub.piston of the material of the reciprocating piston is lower than the coefficient of thermal expansion .sub.screw of the material of the screw, and the disc is an expansion compensation disc, wherein the coefficient of thermal expansion .sub.Disc 1;2 of the material of the expansion compensation disc is greater than the coefficient of thermal expansion .sub.screw of the material of the screw, and to a reciprocating-piston engine having a reciprocating piston of said type, and to a cylinder of a reciprocating-piston engine having a cylinder of said type.

The invention relates to a powdermetallurgically produced valve seat ring having a carrier layer and a function layer. It is the objective of the invention to provide a valve seat ring of the kind mentioned above that offers significantly higher thermal conductivity properties. To achieve this objective and based on a valve seat ring of the kind first mentioned above the invention proposes that the carrier material of the carrier layer has a thermal conductivity higher than 55 W/m*K at a total copper content ranging between >25 and 40% w/w.

The invention relates to a powdermetallurgically produced valve seat ring having a carrier layer and a function layer. It is the objective of the invention to provide a valve seat ring of the kind mentioned above that offers significantly higher thermal conductivity properties. To achieve this objective and based on a valve seat ring of the kind first mentioned above the invention proposes that the carrier material of the carrier layer has a thermal conductivity higher than 55 W/m*K at a total copper content ranging between >25 and 40% w/w.

A hydraulic tool includes a stator, a rotor, and a removable coating. At least one of the stator and the rotor comprises a resilient material. The removable coating has a thickness compensate for expected swelling of the resilient material or an expected contraction of a clearance between the rotor and the stator based on thermal expansion. The removable coating is disposed on a surface of at least one of the rotor and the stator, and the removable coating is formulated to be removed during operation of the hydraulic tool. A method of operating a hydraulic tool includes passing a fluid through the hydraulic tool during rotation of the rotor within the stator and removing at least a portion of the removable coating responsive to rotation of the rotor within the stator as a volume of the resilient material increases responsive to contact with the fluid passing through the hydraulic fluid.

A nickel (Ni) based alloy for forging includes: 0.001 to 0.1 wt. % of carbon (C); 12 to 23 wt. % of chromium (Cr); 3.5 to 5.0 wt. % of aluminum (Al); 5 to 12 combined wt. % of tungsten (W) and molybdenum (Mo) in which the Mo content is 5 wt. % or less; a negligible small amount of titanium (Ti), tantalate (Ta) and niobium (Nb); and the balance of Ni and inevitable impurities.

A housing (10) of a compressor (1) according to the present embodiment includes at least one compression chamber (101) that compresses a gas aspirated into the inside thereof and is composed of a metal-resin composite (16) in which a resin member (14) composed of a thermosetting resin composition and a metal member (12) are bonded to each other. In a case where the metal-resin composite (16) is made into a test piece in which the resin member (14) having a thickness d.sub.1 and the metal member (12) having a thickness d.sub.2 are laminated on and bonded to each other and a ratio of d.sub.1/d.sub.2 is 3, and the test piece is put in a first state where the test piece is disposed, the surface on the resin member (14)-exposed side up, on two supports with no stress applied thereto and a second state where a 1-point bending stress of 140 MPa is applied in a thickness direction to the center of the surface on the resin member (14) side such that the center caves in after the first state, when putting in the first and second states is alternately repeated 1,000,000 times at a frequency of 30 Hz under a temperature condition of 25 C., the metal-resin composite exhibits bending fatigue resistance in which neither peeling nor fracture occurs.

A housing assembly for a rotary engine, has: a rotor housing extending around an axis, the rotor housing having an inner face facing a rotor cavity; side housings secured to opposite sides of the rotor housing, the rotor cavity bounded axially between the side housings; and a seal received within a groove at an interface between the rotor housing and a first side housing, the groove annularly extending around the axis, located outwardly of the inner face, and overlapping a peripheral section of the first side housing, the seal having: an elastomeric member compressed between the peripheral section and the rotor housing; and a shield disposed inwardly of the elastomeric member, the shield having a melting point above a temperature of combustion gases, the shield in contact with both of the peripheral section of the first side housing and the rotor housing.

An eccentric screw pump, with a stator body having a jacket and an elastic inner lining, with which the jacket is provided. According to a first aspect, the jacket and the inner lining are in each case formed with a thermoplastic plastic material. According to a second aspect, the jacket is formed with a thermoplastic plastic material, the inner lining is formed with a material with elastomeric properties and the stator body is produced in a two-component injection molding process or in an at least two-stage casting process. According to a third aspect, the jacket has a screw surface-like outer surface on the outer side at least in sections, which is modified area by area at least by means of additional demolding surfaces. According to a fourth aspect, a stator for an eccentric screw pump is further proposed, having an inner component or inner lining, which is provided for a cooperation with a rotor of the eccentric screw pump and which is formed with a thermoplastic elastomer or a thermoplastic polyurethane. An eccentric screw pump and a method for the production of a stator for an eccentric screw pump are further proposed.