Standard No.:	GB/T 591-2026
English Name:	Marinecastiron flanged stop check valves
Chinese Name:	船用法兰铸铁截止止回阀
Professional Classification:	GB    National Standard
Source Content Issued by:	SAMR, SAC
Issued on:	2026-09-28
Implemented on:	2027-1-1
Status:	to be valid
Superseding:	GB/T 591-2008 Marine cast iron flanged stop check valves
Target Language:	English
File Format:	PDF
Word Count:	8500 words
Translation Price(USD):	255.0
Delivery:	via email in 1~3 business day

GB/T 591-2026 Marine cast iron flanged stop check valves English, Anglais, Englisch, Inglés, えいご This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered. ICS CCS National Standard of the People's Republic of China ‌GB/T 591-2026 Marine cast iron flanged stop check valves 船用法兰铸铁截止止回阀 Issue date: 2026-09-28 Implementation date: 2027-01-01 Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China the Standardization Administration of the People's Republic of China Contents Foreword 1 Scope 2 Normative references 3 Terms and definitions 4 Classification and marking 5 Requirements 6 Test methods 7 Inspection rules 8 Packaging and storage Marine cast iron globe stop-check valves 1 Scope This document specifies the classification and marking, requirements, test methods, inspection rules, and packaging and storage of marine cast iron globe stop-check valves (hereinafter referred to as "stop-check valves"). This document is applicable to the design, manufacture and acceptance of stop-check valves used in marine piping systems for seawater, fresh water, fuel oil and lubricating oil. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies. GB/T 600—2023, General technical requirements for marine piping valves GB/T 898—1988, Double-end studs, *b*_m = 1.25 *d* GB/T 1176—2013, Cast copper and copper alloys GB/T 1348—2019, Spheroidal graphite iron castings GB/T 1958, Geometrical product specifications (GPS) — Geometrical tolerance — Verification GB/T 3032, Marking of marine valves and piping accessories GB/T 4423—2020, Copper and copper alloy drawn bars GB/T 6170—2015, Hexagon nuts, style 1 GB/T 9124.1—2019, Steel pipe flanges — Part 1: PN series GB/T 9439—2023, Grey iron castings GB/T 11698—2026, Length of structural members between flanged pipe connections for marine use CB/T 3530—1993, Handwheels for piping accessories CB/T 3589—1994, Non-asbestos gasket and packing for marine valves CB/T 4196—2011, Marine valve flange — Connection dimensions and sealing surfaces JB/T 6626—2011, Polytetrafluoroethylene braided packings QB/T 4041—2010, Polytetrafluoroethylene sheets 3 Terms and definitions No terms and definitions are required to be defined in this document. 4 Classification and marking 4.1 Types The types of stop-check valves are specified as follows: a) Type A: Straight-through stop-check valve whose flange connection dimensions and sealing surfaces comply with CB/T 4196—2011; b) Type B: Right-angle stop-check valve whose flange connection dimensions and sealing surfaces comply with CB/T 4196—2011; c) Type AS: Straight-through stop-check valve whose flange connection dimensions and sealing surfaces comply with GB/T 9124.1—2019; d) Type BS: Right-angle stop-check valve whose flange connection dimensions and sealing surfaces comply with GB/T 9124.1—2019. 4.2 Basic parameters The basic parameters of the stop-check valves are given in Table 1. Table 1 — Basic parameters of stop-check valves 4.4 Product marking The product marking method for stop-check valves is as follows: 5 Requirements 5.1 Materials 5.1.1 The materials for the main parts of the stop-check valve shall comply with the provisions of Table 4. Production may commence only after the materials have been inspected and found to be qualified. Table 4 — Materials for main parts of stop-check valves 5.1.2 For castings, at least three ladle test specimens with furnace numbers shall be provided for each heat, and the retention period shall not be less than 3 years. 5.2 Strength The strength of the stop-check valve shall comply with the provisions of 4.14 in GB/T 600—2023. 5.3 Tightness The tightness of the stop-check valve shall comply with the provisions of 4.15 in GB/T 600—2023. 5.4 Dimensions and dimensional tolerances 5.4.1 The wall thickness of the stop-check valve shall comply with the provisions of 4.2 in GB/T 600—2023, and the wall thickness tolerance shall comply with the provisions of 4.5.1 in GB/T 600—2023. 5.4.2 The dimensional tolerances of the stop-check valve shall comply with the provisions of 4.5 in GB/T 600—2023. 5.4.3 The structural length tolerances of Type A and Type B stop-check valves shall comply with the provisions of the construction drawings, and the structural length tolerances of Type AS and Type BS stop-check valves shall comply with the provisions of GB/T 11698—2026. 5.5 Geometrical tolerances The geometrical tolerances of the stop-check valve shall comply with the provisions of 4.7 in GB/T 600—2023. 5.6 Assembly The assembly of the stop-check valve shall comply with the provisions of 4.10 in GB/T 600—2023. 5.7 Appearance The appearance of the stop-check valve shall comply with the provisions of 4.11 in GB/T 600—2023. 5.8 Weight The weight of the stop-check valve shall comply with the provisions of Table 2 and Table 3, and its positive weight deviation shall not exceed 4 % of the design weight.