Manufacturing process for asbestos-free sealing gasket

Abstract

The invention discloses a manufacturing process for an asbestos-free sealing gasket. An asbestos-free beater-addition sealing paperboard is manufactured through a beater-addition process by taking aramid fibre 1414 pulp as a main material, matching cellulose fibres and mineral cotton fibres as hybrid fibres to replace asbestos fibres, selecting a mixture of butadiene-acrylonitrile latex and styrene-butadiene latex as latex, selecting kaolin, talcum powder and mica powder as filler, and determining a reasonable formula range of the compositions, wherein the asbestos-free beater-addition sealing paperboard has the ignition loss of less than or equal to 35 percent, the compression ratio of equal to 25+ / - 5 percent, the rebound rate of greater than or equal to 45 percent, the tensile strength of greater than or equal to 5 MPa, and the creep relaxation rate of less than or equal to 30 percent.

Description

technical field [0001] The invention relates to a manufacturing process of a non-asbestos sealing gasket. Background technique [0002] Non-metallic gaskets are mainly made of non-metallic materials such as rubber, resin, polytetrafluoroethylene, and asbestos. The non-metallic gasket containing asbestos shows its excellent tensile strength, creep relaxation performance, heat resistance and medium resistance, etc., and the sealing gasket made of it is particularly superior in high temperature and high pressure sealing occasions. However, during the production or use of asbestos-containing sealing gaskets, asbestos will split into extremely fine meta-fibers, and the micro-fibers will cause extremely serious harm to human health. [0003] It has been recognized internationally that asbestos is a carcinogen. In the 1970s, the developed industrial countries first proposed the asbestos-free plan. After more than 20 years of hard work, the United States, Japan, Australia and oth...

AI Technical Summary

Problems solved by technology

Nowadays, many industrially developed countries in the world have promoted non-asbestos materials to various application fields, and completely banned the use of any asbestos-containing materials; most of the non-asbestos sealing gaskets researched and developed in China are traditional sealing products. There are large differences in the quality of products among them, and the performance indicators also need to be improved.

[0004] The early asbestos-free gaskets were mainly prepared by rubber mixing and molding technology, but with the improvement of the requirements for sealing products in the industrial field, the defects of the molding method are becoming more and more obvious. The production efficiency is low, and the size is easily limited by equipment. The mechanical properties of the product are poor, and failure and leakage are prone to occur during long-term use; after industrial development, the compression into tension method has emerged. This method requires a large investment in equipment in the early stage and requires high quality workers, especially in terms of formula and production technology. The control of parameters is particularly strict