摘要:
A corrosion-resistant pipe coupling made of carbon steel has on its inner surface an intermediate annular projection directed radially inward. At least an innermost part of the annular projection is formed of corrosion-resistant material such as stainless steel. The annular projection may be covered by a corrosion-resistant annular member which is secured by friction welding, electron beam welding, an adhesive or mechanical engagement. The annular member prevents corrosion of the coupling by corrosive fluids flowing in pipes.
摘要:
A corrosion-resistant pipe coupling made of carbon steel has on its inner surface an intermediate annular projection directed radially inward. At least an innermost part of the annular projection is formed or corrosion-resistant material such as stainless steel. The annular projection is covered by a corrosion-resistant annular member or which is secured by friction welding, electron beam welding, an adhesive or mechanical engagement. The annular member prevents corrosion of the coupling by corrosive fluids flowing in pipes.
摘要:
A double-wall composite pipe is produced by inserting an inner pipe in an outer pipe, filling the inner pipe with cold water under pressure to cause the inner pipe to expand plastically into tight contact with the outer pipe, applying heat to the outer part of the outer pipe by high-frequency induction heating, thereby to establish a locally heated zone thereof around the circumference thereof and causing the heated zone to travel from one end to the other end of the outer pipe thereby to cause it to successively expand locally in diameter in the travelling heated zone. The pressure in the inner pipe then is removed, the pipes thereafter being permitted to attain the ambient temperature, thereby to obtain an interference fit therebetween.
摘要:
A radiographic test is conducted on a welded portion of a pipe or the like to form a radiographic image, which is introduced into a computer. Volumetric defects and planar defects in the radiographic image are emphasized and extracted by separate methods to obtain a volumetric candidate defect image and a planar candidate defect image. The candidate defect images are then combined to form a single image in which defects can be easily identified. Features of defects in the images are measured, and a set of interference rules is applied to the measured features. Each inference rule gives a degree of certainty that a defect is of a certain type. The degrees of certainty determined by a plurality of the rules are collated to obtain a total degree of certainty, and the type of a defect is inferred from the total degree of certainty.
摘要:
A composite structure is manufactured by joining a first material, preferably made of a magnetically permeable material and having a first joining surface in which a recess having an overhang surface is formed, to a second material, preferably made of an electrically conductive material and having a second joining surface to be joined to the first joining surface of the first material. On the second joining surface is integrally formed a protrusion having an outer configuration substantially corresponding to the inner shape of the recess. The first and second materials are firmly mechanically joined to each other by, for example, a casting method, a rolling method, a pressing method, or a method utilizing plastic flow of the second material.
摘要:
A method of producing an anchor bonded composite plate. Anchor cavities are formed in a base plate by placing a forming plate with a circular hole therethrough over the base plate at a selected anchor cavity location. A punch placed through the circular hole then applies a punching force to the base plate, thereby forming in the base plate an annular mound with a concentrically punched hole. The mound is next pressed with a leveling plate to cause the material of the mound to flow inside the punched hole forming an anchor cavity with an overhanging internally tapered surface. A cladding plate with a plurality of anchor holes is then placed on the base plate with its holes aligned with the cavities of the base plate. An anchor pin is inserted in the thus aligned openings and is plastically deformed to mechanically bond the plates together. The cladding plate and the base plate may be made of an aluminum alloy and a hard steel, respectively. The composite plate thus produced is applicable as a reaction plate for a linear motor vehicle and as a tank material for a liquid natural gas holder.
摘要:
A multiple-wall pipe structure having at least two pipes tightly fitted one within another, one of which is of a corrosion-resistant material whereas the other is of a noncorrosion-resistant material. In order to protect against corrosion the end faces of the noncorrosion-resistant pipe and the seams between the two pipes, either during storage in the form of discrete pipe sections or in use by being welded or otherwise jointed end to end, a pair of anticorrosion rings of a corrosion-resistant material are integrally attached to the opposite ends of the fitted pipes so as to cover at least the end faces of the noncorrosion-resistant pipe and to seal the seams therebetween.
摘要:
For reducing the diameter of any axially limited part of a metal tube, that part is heated externally by an annular heater while at least the adjacent part or parts of the metal tube are being cooled and held at a temperature sufficiently low to limit the free thermal expanison of the heated part. On cooling, the part that has been heated becomes less in diameter than the other portions of the metal tube. The complete length of the metal tube can likewise be reduced in diameter by moving the annular heater and the metal tube relative to each other in the longitudinal direction of the tube from one end to the other while at least the adjacencies of the part being heated are being cooled as by water. The same method is adaptable for the fabrication of wear-resistant dual wall pipe for the transportation of fluids, as is also disclosed herein.
摘要:
A panel structure is fabricated by stretching a skin plate with a tensile stress below the elastic limit stress thereof, securing this plate onto a framework with the plate under a constraining tensile stress and with portions thereof to which the constraining stress is not being fully applied being heated thereby to cause thermal expansion thereof, removing the constraining stress, and permitting the plate to cool and thereby to undergo thermal contraction and deformation, thereby producing tensile residual stress within the plate, whereby occurrence of welding deformations in the plate on the finished panel is prevented. Depending on the necessity, the skin plate may be prestretched with a stress exceeding the yield point thereof before the above described panel fabrication.
摘要:
An outer pipe is diametrically expanded by heating and an inner pipe is diametrically contracted by cooling with a coolant introduced into the inner pipe to produce between the pipes a clearance just sufficient for insertion of the inner pipe into the outer pipe, and then the coolant is pressurized to expand the inner pipe against and together with the outer pipe, the pressure being removed after the pipes have expanded to a specific diameter of the joint therebetween. The tightness of the fit between the pipes due to the expansion is further increased by the subsequent thermal shrinkage of the outer pipe and thermal expansion of the inner pipe.