GB/T 19675.2-2023Reinforced flexible graphite gaskets for pipe flanges—Part 2: Class designated (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

This document is Part 2 of GB/T 19675 "Flexible graphite composite reinforced gaskets for pipe flanges". GB/T 19675 has been released The following parts.

---Part 1: PN series;

---Part 2: Class Series.

This document partially replaces GB/T 19675.1-2005 "Dimensions of metal punched tooth plates and flexible graphite composite gaskets for pipe flanges" and GB/T 19675.2-2005 "Technical Conditions for Metal Punch Tooth Plate Flexible Graphite Composite Gaskets for Pipe Flanges". Compared with GB/T 19675.1-2005 and GB/T 19675.1-2005, in addition to structural adjustments and editorial changes, the main technical changes are as follows.

a) Added gasket type (see Chapter 4);

b) Added process requirements for gasket production (see 5.2);

c) Increased dimensions of reinforced gaskets with bolt holes for flat flanges (see Table 3);

d) Added flat ring type reinforced gaskets for NPS 1/2. Dimensions (see Table 4, Table 5 and Table 6);

e) Changed the dimensional limit deviation of gaskets (see Table 7 and Table 8, Table 1 and Table 2 of GB/T 19675.2-2005);

f) Changed the performance requirements of gaskets (see 6.4, 3.4 of GB/T 19675.2-2005);

g) Changed the marking method of gaskets (see 9.1, Chapter 5 of GB/T 19675.1-2005);

h) Added storage period and related regulations (see 9.4.3).

Introduction

Flexible graphite composite reinforced gasket is a commonly used sealing gasket in industrial fluid equipment and pipeline flange connections. GB/T 19675.1-2005 "Dimensions of flexible graphite composite gaskets with metal punched tooth plates for pipe flanges" and GB/T 19675.2-2005 "Flexible metal punched tooth plates for pipe flanges" It has been more than ten years since the release and implementation of "Technical Conditions for Graphite Composite Gaskets". During this period, with the update and improvement of gasket production technology, the working conditions and environments of use have become more diverse.

It has been diversified and developed, and the pipe flange standard adapted to it has been revised twice. Therefore, in order to be consistent with the current pipe flange standards PN and Class Compatible with each series, the standards of flexible graphite composite reinforced gaskets are also divided into PN series and Class series accordingly.

GB/T 19675 aims to establish the necessary requirements for the design, manufacturing, performance and selection of flexible graphite composite reinforced gaskets. It is planned to be composed of two parts composition.

---Part 1: PN series. The purpose is to establish the specifications, dimensions and technical requirements of PN series flexible graphite composite reinforced gaskets.

---Part 2: Class Series. The purpose is to establish the specifications, dimensions and technology of Class series flexible graphite composite reinforced gaskets.

1 Scope

This document stipulates the type and code, materials and processes, requirements, and inspection of flexible graphite composite reinforced gaskets for Class-marked pipe flanges. Inspection methods, inspection rules, marking, marking, packaging, transportation and storage.

This document is applicable to nominal pressures from Class150 to Class600 and nominal sizes from DN15 to DN600 (NPS 1/2 ~ NPS 24) the pipe flange uses flexible graphite composite reinforced gasket.

2 Normative reference documents

The contents of the following documents constitute essential provisions of this document through normative references in the text. Among them, the dated quotations For undated referenced documents, only the version corresponding to that date applies to this document; for undated referenced documents, the latest version (including all amendments) applies to this document.

GB/T 2520 Cold-rolled electro-tin-plated steel plates and steel strips

GB/T 3280 Stainless steel cold-rolled steel plates and strips

GB/T 12385-2008 Gasket sealing performance test method for pipe flanges

GB/T 12622-2008 Test method for compression rate and rebound rate of gaskets for pipe flanges

JB/T 6628 Flexible graphite composite reinforced (plate) pad

3 Terms and definitions

There are no terms or definitions to be defined in this document.

4 Type and code