Standard No.:	GB/T 26653-2026
English Name:	Exhaust manifold castings
Chinese Name:	排气歧管铸件
Professional Classification:	GB    National Standard
Source Content Issued by:	SAMR, SAC
Issued on:	2026-02-27
Implemented on:	2026-9-1
Status:	to be valid
Superseding:	GB/T 26653-2011 Exhaust manifold iron castings
Target Language:	English
File Format:	PDF
Word Count:	9000 words
Translation Price(USD):	270.0
Delivery:	via email in 1~3 business day

GB/T 26653-2026 Exhaust manifold castings 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 26653-2026 Exhaust manifold castings 排气歧管铸件 Issue date: 2026-02-27 Implementation date: 2026-09-01 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 Designation Selection Principles 5 Technical Requirements 6 Test Methods 7 Inspection Rules 8 Marking, Certificate of Conformity, Packaging, Transport and Storage Exhaust manifold castings 1 Scope This document specifies the designation selection principles and technical requirements for exhaust manifold castings for internal combustion engines (hereinafter referred to as "castings"), describes the corresponding test methods, and specifies the inspection rules as well as requirements for marking, certificate of conformity, packaging, storage and transport. This document applies to the manufacture of exhaust manifold castings for internal combustion engines. 2 Normative references The contents of the following documents constitute essential provisions of this document through normative reference. For dated references, only the edition cited applies. For undated references, the latest edition (including all amendments) applies. GB/T 223.3 Methods for chemical analysis of iron, steel and alloy — The diantipyrylmethane phosphomolybdate gravimetric method for the determination of phosphorus content GB/T 223.4 Iron, steel and alloy — Determination of manganese content — Potentiometric or visual titration method GB/T 223.5 Iron, steel and alloy — Determination of acidsoluble silicon and total silicon content — Reduced molybdosilicate spectrophotometric method GB/T 223.11 Iron, steel and alloy — Determination of chromium content — Titration method and spectrophotometric method GB/T 223.12 Methods for chemical analysis of iron, steel and alloy — The sodium carbonate separationdiphenylcarbazide photometric method for the determination of chromium content GB/T 223.23 Iron, steel and alloy — Determination of nickel content — Dimethylglyoxime spectrophotometric method GB/T 223.25 Methods for chemical analysis of iron, steel and alloy — The dimethylglyoxime gravimetric method for the determination of nickel content GB/T 223.26 Iron, steel and alloy — Determination of molybdenum content — Thiocyanate spectrophotometric method GB/T 223.38 Methods for chemical analysis of iron, steel and alloy — The ionexchange separation gravimetric method for the determination of niobium content GB/T 223.40 Iron, steel and alloy — Determination of niobium content — Chlorosulfophenol S spectrophotometric method GB/T 223.58 Methods for chemical analysis of iron, steel and alloy — The sodium arsenitesodium nitrite titrimetric method for the determination of manganese content GB/T 223.60 Iron, steel and alloy — Determination of silicon content — Gravimetric method GB/T 223.64 Iron, steel and alloy — Determination of manganese content — Flame atomic absorption spectrometric method GB/T 223.68 Methods for chemical analysis of iron, steel and alloy — The potassium iodate titrimetric method after combustion in a tube furnace for the determination of sulfur content GB/T 223.71 Methods for chemical analysis of iron, steel and alloy — The gravimetric method after combustion in a tube furnace for the determination of carbon content GB/T 228.1 Metallic materials — Tensile testing — Part 1: Method of test at room temperature GB/T 231.1 Metallic materials — Brinell hardness test — Part 1: Test method GB/T 3821 Small and medium power internal combustion engines — Cleanliness limits and measurement methods GB/T 5611 Foundry terminology GB/T 5677 Castings — Radiographic testing GB/T 5678 Sampling methods for spectrochemical analysis of casting alloys GB/T 6060.1 Surface roughness comparison specimens — Part 1: Cast surfaces GB/T 7216 Metallographic test for grey cast iron GB/T 9441 Metallographic test for spheroidal graphite cast iron GB/T 9443 Steel and iron castings — Penetrant testing GB/T 9444 Steel and iron castings — Magnetic particle testing GB/T 11170 Stainless steel — Determination of multielement contents — Spark discharge atomic emission spectrometric method (Routine method) GB/T 11351-2017 Mass tolerances for castings GB/T 14203 General rules for spark discharge atomic emission spectrometry GB/T 15056 Evaluation method of surface roughness for castings GB/T 20066 Steel and iron — Sampling and preparation of samples for the determination of chemical composition GB/T 24234 Cast iron — Determination of multielement contents — Spark discharge atomic emission spectrometric method (Routine method) GB/T 26656 Metallographic test for compacted graphite cast iron GB/T 34904 Spheroidal graphite iron castings — Ultrasonic testing GB/T 42124.3-2025 Geometrical product specifications (GPS) — Dimensional and geometrical tolerances for moulded parts — Part 3: Dimensional tolerances, geometrical tolerances and machining allowances for castings 3 Terms and definitions For the purposes of this document, the terms and definitions given in GB/T 5611 apply. 4 Designation selection principles Exhaust manifold castings may be made of grey cast iron, spheroidal graphite cast iron, compacted graphite cast iron or cast steel according to the operating temperature. Specific selection guidance is given in Annex A. 5 Technical requirements 5.1 Chemical composition 5.1.1 The chemical composition of cast iron of designations HT200, HT250, RuT300, QT400-15, QT400-18 and QT450-10 shall not be used as acceptance criteria. The chemical composition of cast iron of other designations shall comply with Table 1. 5.1.2 The chemical composition of cast steel castings shall comply with Table 2. 5.2 Mechanical properties The mechanical properties of castings shall comply with Table 3. 5.3 Metallographic structure 5.3.1 The metallographic structure of cast iron castings shall comply with Table 4. When special requirements exist, the purchaser shall specify them on the product drawing or in the supply contract. The metallographic structure of cast steel castings shall not be used as an acceptance criterion. 5.3.2 Castings may be supplied in the ascast condition. Heat treatment methods may be used to achieve the required mechanical properties and metallographic structure. 5.4 Geometric shape and dimensional tolerances The geometric shape and dimensions of castings shall comply with the requirements of the drawing or relevant technical specifications. When no special requirements are specified, the dimensional tolerance grade of castings shall reach Grade DCTG8 in GB/T 42124.3-2025, and the geometrical tolerance grade shall comply with Grade GCTG6 in GB/T 42124.3-2025. The mismatch value shall not affect machining or assembly, and the wall thickness after mismatch shall not be less than the minimum permissible wall thickness. 5.5 Surface quality 5.5.1 Castings shall be cleaned. The dressing of residual runners and risers, scabs, flash, burrs, etc., shall comply with the requirements of the drawing or the supply agreement between the supplier and the purchaser. 5.5.2 The surface roughness of the internal and external surfaces of castings shall be according to the purchaser's drawing requirements. When not specified on the drawing, it shall be selected according to GB/T 6060.1. 5.5.3 Castings shall be shot blasted to remove adhering sand, scale, etc. 5.6 Internal quality 5.6.1 Casting defects not permitted in castings The following casting defects are not permitted in castings: a) Castings shall not have casting defects (such as cracks, cold shuts, shrinkage cavities, slag inclusions, etc.) that affect the service performance of the casting. b) The internal cavity of castings shall not have fins, scabs or other casting defects that affect the exhaust condition. c) No casting defect of any size shall be present simultaneously on the same area of the internal and external surfaces of the casting wall. 5.6.2 Casting defects permitted in castings Without affecting service performance, the following casting defects are permitted in castings: a) Casting defects are permitted in the bolthole area of castings, provided they do not exceed onefifth of the total depth of the bolthole, and the distance from the defect to the end of the threaded hole shall not be less than 3 threads. The defect shall not affect assembly or the strength after assembly. b) Slight dispersed shrinkage is permitted in the hot spot area of castings. The shrinkage area shall not exceed onefifth of the crosssection of the shrinkage area. The thickness of the shrinkage area from the internal wall shall not be less than the wall thickness, and it shall not affect machining, reduce the strength of the casting or impair assembly performance. c) Castings are permitted to have casting defects that can be removed by machining. d) The types, quantity and extent of casting defects permitted on nonmachined surfaces and inside castings shall comply with the requirements of the purchaser's drawings, technical specifications or the supply agreement between the supplier and the purchaser. e) Casting defects that do not affect service performance may be repaired. 5.7 Cleanliness The cleanliness of castings shall comply with the requirements of the drawing. 5.8 Gas tightness Castings shall be subjected to a gas tightness test after machining according to the requirements of the drawing or product technical specifications. 5.9 Mass tolerances The mass tolerances of castings shall comply with the requirements of the drawing or relevant technical specifications. When no special requirements are specified, the mass tolerance grade of castings shall comply with Grade MT8 in GB/T 11351-2017.