GB/T 21873-2025 Rubber seals—Joint rings for water supply,drainage and sewerage pipelines—Specification for materials

Scope

This document specifies the material requirements for vulcanized rubber sealing rings used in the following pipelines:
a) Pipelines for cold drinking water (below 50 ℃);
b) Drainage, sewage, and rainwater pipelines (continuous flow water not exceeding 45 ℃ and intermittent flow water not exceeding 95 ℃).
The markings of various sealing rings specified in this document are determined based on the type, application, and requirements of the sealing rings.
This document also specifies the general requirements for finished sealing rings. Since the performance of pipeline joints is related to the performance of sealing ring materials, the geometry of sealing rings, and the design of joints, relevant product standards also stipulate additional requirements for specific application scenarios. This document is intended to be used in conjunction with product standards that specify the performance requirements of joints when appropriate.
This document applies to all pipeline joint sealing rings, including cast iron pipes, steel pipes, ceramic pipes, cement pipes, reinforced cement pipes, plastic pipes, and fiberglass-reinforced plastic pipes.
This document applies to the elastomeric parts of composite or non-composite rubber sealing rings. For composite sealing rings with a material hardness of 76 IRHD to 95 IRHD, the tensile elongation, compression permanent deformation, and stress relaxation requirements only apply when the rubber is directly involved in sealing or when long-term sealing stability is required.
This document also applies to interface sealing rings that use closed-cell foam rubber materials as part of the sealing ring.

Development Information

Replace the following standards

Referenced Standards

Adopt standards

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