Testing method for creep relaxation of non-metal sealing gasket

Abstract

The invention discloses a testing method for creep relaxation of a non-metal sealing gasket. The testing method comprises the following steps of (1) clamping the gasket; (2) tightening to an initial torque; (3) insulating by an aging box; (4) carrying out air cooling to room temperature; and (5) testing the residual torque, and screwing a torque bolt again by using a torque wrench so as to test the residual torque. Compared with the similar products, the testing method for creep relaxation of the non-metal sealing gasket, disclosed by the invention, has the advantages that under the same control condition, the capability of given compression stress is maintained along with the passage of time, and the creep relaxation of the gasket is evaluated by the degree of bolt torque loss; and a testing device is simple, a finished gasket can be directly tested on a production site, and the testing efficiency is high.

Description

technical field [0001] The invention relates to the field of testing non-metallic sealing gaskets, in particular to a method for testing the creep relaxation of non-metallic sealing gaskets. Background technique [0002] Non-metallic sealing gaskets are made of plate-like materials through stamping or cutting processes, and are used for sealing connections between pipes and flanges. The gaskets are fixed between the two parts by bolts for sealing. [0003] Creep relaxation rate is an important quality index in evaluating the sealing properties of non-metallic gasket materials. The appropriate creep relaxation rate is related to the material selection of the gasket. A higher creep relaxation rate will cause the gasket to have poor sealing performance and short service life. [0004] There are two methods for testing the creep relaxation rate of non-metallic gasket materials: residual load method and ultrasonic length measurement method. [0005] 1. Residual load method: Und...

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Problems solved by technology

[0022] 1) Plan 1 must be completed in a standard laboratory, and it needs to be equipped with computers, air conditioners, and thermohumidifiers. It takes half a month to complete a round of test data, and the test efficiency is low and the cost is high;

[0023] 2) The ultrasonic length measurement method of option two has many influencing factors, the bolts are prone to failure, and the effective data is difficult to collect

[0024] 3) Both schemes have requirements for the size and specifications of the test samples, and the gaskets used on our engines are irregular

The creep relaxation test cannot be directly performed on the finished gasket, but only on the non-metallic gasket raw material plate. The performance of the raw material cannot fully represent the performance of the formed gasket, resulting in poor accuracy of the creep relaxation test of the formed gasket.

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