Abstract: A ceramic coating bonded to an iron tubular member comprising a bonding layer formed on a surface of the iron tubular member by a reaction of an iron tubular oxide layer of the iron tubular member and a silicate; and an iron oxide diffusion-preventing layer produced from fine metal oxide particles or an organometallic binder by firing on a surface of the bonding layer. The ceramic coating may further comprises an oxidation-preventing layer, a heat-insulating layer, a refractory layer or a thin dense protective layer. It may be produced by coating the surface of the iron tubular member with a silicate binder to form a layer which is then converted to a bonding layer by a heat treatment in a steam atmosphere; coating the surface of the bonding layer with fine metal oxide particles or an organometallic binder to form an iron oxide diffusion-preventing layer; and after curing and drying firing the resulting ceramic coating in an atmosphere having an oxygen partial pressure of 10 mmHg or less.

Abstract: A method of manufacturing a heat resistant member includes the step of designing the shape of the heat resistant member, including the substeps of estimating thermal stress of the heat resistant member by heating a model formed by a high-thermal expansion material which has a similar shape to the desired shape of the heat resistant member while the model is restrained and also while it is free. The high-thermal expansion material is different from the material of the member being modeled and has a thermal expansion coefficient greater than that of the material of the member being modeled. Additionally, the step of designing includes the substeps of measuring the strain of the model at each of a plurality of predetermined positions while the model is heated by strain gauges adhered to predetermined positions on the model, and calculating the stress at each predetermined position from the difference in measured strain values between the restraint state and the free state.

Abstract: The gear tester includes (a) a first driving shaft driven by a motor and having a first driving gear fixed thereto; (b) a second driving shaft parallel with the first driving shaft and having a second driving gear fixed thereto; (c) a pair of intermediate gears meshing with each other, via which the first and second driving shafts are operably connected to each other; (d) a frame rotatably supporting the pair of intermediate gears, the frame being movable in a transverse direction so that a rotation phase difference is generated between the first and second driving gears depending upon the movement of the frame; and (e) a pair of test gears meshing with each other, one of which is fixed to the first driving shaft and the other of which is fixed to the second driving shaft. By moving the frame, a torque load is applied to test gears.

Abstract: A method of estimating a thermal stress of a heat-resistant member, part or the whole of which is to be heated to a high temperature, comprising heating a model formed by a high-thermal expansion material and having a shape similar to that of the heat-resistant member; and measuring a thermal strain of the model at each of predetermined positions by strain gauges adhered thereto.

Abstract: A model for measuring stress distribution constituted by a light, integral polyurethane foam having little unevenness in density, the polyurethane foam being at predetermined sites provided with undercoating layers, to each of which a resistance wire strain gauge is attached via an adhesive, each of the undercoating layers having a thickness of 50-300 .mu.m and being made of a material which is unreactive with, hardly penetrable into and softer than the polyurethane foam. The stress distribution measurement is conducted by supporting the polyurethane foam model by one or more support members at positions corresponding to the restraint sites of an actual metal member, and applying a load to the polyurethane foam model at a position corresponding to the site of the actual metal member to which a load is actually applied, thereby measuring a stress distribution in the polyurethane foam model under substantially the same restraint conditions as in the actual metal members.

Abstract: A ceramic coating bonded to a metal member comprising a bonding layer formed by the reaction of an oxide layer formed on a surface of said metal member in advance and a silicated; and an anti-oxidizing first ceramic layer formed on said bonding layer and comprising inorganic flaky particles burned to have a cross-linked laminate structure.

Abstract: An apparatus for testing a heat-insulating tubular member having at least one tubular portion comprising a combustion chamber connected to the tubular portion, a burner mounted in each combustion chamber, and an air line and a fuel supply line both connected to the burner. It may further comprise an air line for increasing exhaust gas pressure which opens on the inner wall of the combustion chamber near the burner.

Abstract: An exhaust device whose inner surface is coated with a heat-insulating layer and a refractory layer. Each layer is formed by conducting at least one cycle of the steps of: (a) coating the inner surface with an inorganic binder solution, (b) immediately adhering a coating powder to the binder solution layer so that the powder is fully and uniformly impregnated with the binder solution, and (c) drying and solidifying it by heat treatment. The coating layer does not suffer from cracking, peeling and breakage.

Abstract: A method of producing a nodular graphite cast iron having high strength and toughness in shorter time and with reduced production cost. The method comprises the following steps: rapidly cooling the casting, which has been removed from the mold at a predetermined temperature above the A.sub.1 transformation point, at such a cooling rate as not to permit the generation of pearlite structure, after having been held for a predetermined time within the austenite temperature range or immediately after having been removed from the mold; once stopping the rapid cooling at a temperature above the Ms point; slowly cooling the casting within a temperature range above the Ms point for a predetermined time or holding the casting at a constant temperature within a predetermined temperature range above the Ms point for a predetermined time; and cooling the casting slowly down to the normal temperature.

Abstract: A method of and apparatus for fusion bonding a continuous synthetic thermoplastic resin fastener strip having a fastener profile portion and a base portion opposite the profile, to a continuous film substrate. The substrate is advanced continuously through a bonding zone. Continuous direct transit of the fastener strip is effected from thermoplastic extruder downwardly through a short distance to the bonding zone, so that in the short transit distance the fastener strip will retain substantial residual thermoplastic fusion temperature. The fastener profile portion is chilled while the strip is in transit to the bonding zone, solidified and stabilized, but the base portion is left at sufficient residual fusion temperature to remain thermoplastic to the bonding zone where assembly of the strip and substrate is effected by fusion bonding of the base portion to the substrate.

Abstract: A wheel plate of a coupler for coupling a tractor and a trailer. The wheel plate has a lubricating arrangement for lubricating the sliding surfaces in the coupling. The lubricating arrangement includes a main groove formed in a central portion of the sliding surface of the wheel plate and surrounding the pivot shaft of the coupler, and a plurality of convolution grooves formed in the sliding surface of the wheel plate along convolution curves starting from and surrounding the main groove. The convolution grooves are communicated at their both ends with the main groove.