GB/T 1241-2008Marine forged steel male thread stop-check valves (English PDF)

Foreword

This standard replaces GB/T 1241-1983 "Marine forged steel male thread stop and check valves." The standards are compared with the GB/T 1241-1983 the following major changes.

--- Cutoff valve material modified by Q235-A steel 20 steel;

--- Increased the seal down requirements;

--- Increased test methods, inspection rules, marking, packaging, and other content. The standard proposed by China State Shipbuilding Corporation. This standard by the National Marine Machinery Standardization Technical Committee piping attachment points Technical Committee. This standard was drafted. Jiangxi Marine Valve Factory, Technical and Economic Research Institute of China Shipbuilding Industry. The main drafters of this standard. Dingyan Yuan, Luo Yuan hair. This standard replaces the standards previously issued as follows:

--- GB/T 1241-1976. Marine forged steel male thread stop and check valves

1 Scope

GB/T 1241-2008 is the Chinese national standard on marine forged steel male thread stop-check valves, in the field of shipbuilding and marine structures. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 3 February 2008 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 1 August 2008. Classification: ICS 47.020.30, CCS U52. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This standard specifies the Marine forged steel male thread stop and check valves (hereinafter referred to as the cut-off valve) classification and marking requirements, test methods, Inspection rules, marking, packaging and storage. With a cut-off valve is located This standard applies to fuel, oil, fresh water, and the air temperature does not exceed 250 °C steam ship piping system Design, manufacture and acceptance.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent All amendments (not including errata content) or revisions do not apply to this standard, however, encourage an agreement in accordance with this standard Whether the parties can study the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 600 marine piping valves General technical requirements

GB/T 699-1999 quality carbon structural steel

GB/T 700-2006 carbon structural steel

GB/T 1220-2007 stainless steel rod

GB/T 1958 Geometrical Product Specifications (GPS) shape and position tolerance testing requirements Flag

GB/T 3032 Ship pipeline accessories

GB/T 9440-1988 Malleable Iron Castings

GB/T 17107-1997 forging grades and mechanical properties of structural steel CB56 pipe nipple flat shoulder CB/T 3589-1994 Marine valve non-asbestos gaskets and packing material

3 Classification and Marking

3.1 Off valve is divided into two types as follows: A type

--- Feed-off valve; Type B

--- right angle cut-off valve.

3.2 Basic parameters The basic parameters of the cut-off valve are shown in Table 1. Table

1 Basic parameters of the cut-off valve Type Nominal pressure PN/MPa Nominal diameter DN/mm A, B 4.0 10 ~ 32

3.3 Structure and basic dimensions Stop check valve structure and basic dimensions in Figure 1 and Table 2.