Device and method for expanding diameter of shape memory alloy pipe joint

Abstract

The invention discloses a diameter-expanding device and method for a shape memory alloy pipe joint. The diameter-expanding device includes a diameter-expanding rod, a diameter-expanding valve mold, a material retaining plate, a spacer, a base, and bolts. The spacer is connected to the base by four bolts. The expansion rod is inserted into the central positioning hole of the base, the expansion valve mold is placed on the spacer around the expansion rod, the baffle plate is connected to the spacer by four bolts, and the step surface of the expansion valve mold It is located under the stepped surface of the center hole of the baffle plate; during the expansion operation, the shape memory alloy pipe joint is set on the top cylinder of the expansion valve mold and forms a clearance fit with the expansion valve mold, and the small end of the expansion rod faces When placed down, the expansion rod moves downward under force to expand the expansion valve mold, and the expansion valve mold moves evenly to the outer periphery under force to expand the diameter of the pipe joint. The invention has ingenious conception, compact structure, convenient installation and use, easy control of diameter expansion speed and diameter expansion amount, uniform overall expansion expansion deformation, and improves the quality of pipe joint expansion forming.

Description

technical field [0001] The invention relates to the technical field of pipe joint diameter expanding equipment, in particular to a shape memory alloy pipe joint diameter expanding device and method. Background technique [0002] Shape memory alloy (SMA) is a new type of functional material developed in the early 1960s, and has been widely used in aviation, aerospace and medical fields. Shape memory alloys have a shape memory effect due to their thermoelastic martensitic transformation, that is, the material in the austenitic state is cooled below the martensitic transformation initiation temperature (Ms), and a martensitic transformation occurs. The material under the condition is unloaded after being deformed. When the temperature rises above the martensitic inverse transformation start temperature (As), martensite transforms to austenite, and the deformation generated at low temperature can be recovered. Pipe joints are one of the most successful engineering applications ...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a shape-memory alloy pipe joint expansion device, which solves the problem that the prior art expansion device will cause local deformation of the pipe joint and damage the inner ridge of the pipe joint, thereby reducing the connection strength, sealing performance and service life of the pipe joint , the problem that the molding quality is not easy to guarantee

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