GB/T 908-2019Forged bars for dimensions,shape,weight and tolerances (English PDF)
锻制钢棒尺寸、外形、重量及允许偏差
This is a limited preview
Buy now to download the full PDF (15 pages)
Need quotation for your management?
Get a formal quotation for GB/T 908-2019 in 30 minutes.
Issued by
SAMR; SAC
Level / Type
National · Recommended
Issue date
June 4, 2019
Implementation date
May 1, 2020
Scope
GB/T 908-2019 is the English-translated version of 锻制钢棒尺寸、外形、重量及允许偏差.
GB/T 908-2019 is the Chinese national standard for the dimensions, shape, weight and tolerances of forged steel bars.
It classifies them by the surface condition in which they are delivered - hot-forged, polished and machined - and gives the section shapes of round, square and flat bars, their sizes and theoretical weights in normative Annex A, and the allowable size deviations of each group.
It also fixes the delivery length, normally not less than 1500 mm, the curvature limits per metre and over the whole length, and the cutting slope of the sawn end faces.
It applies to forged round and square bars of 40 mm to 1000 mm and to flat bars 20 mm to 800 mm thick and 40 mm to 1500 mm wide. It replaces GB/T 908-2008, was issued on 4 June 2019 and has applied since 1 May 2020.
Found what you need?
Document preview — GB/T 908-2019
National Standard of the People's Republic of China
- ICS
- 77.140.60
- Classification
- H 44
- Replacing
- GB/T 908-2008
Issued by: State Administration for Market Regulation; Standardization Administration of the PRC
Contents
- Foreword3
- 1 Scope5
- 2 Classification5
- 3 Section shape5
- 4 Section size, weight and allowable deviation6
- Annex A (normative) Size and theoretical weight of forged bars13
Foreword
This Standard was drafted in accordance with the rules given in GB/T 1.1-2009.
This Standard replaces GB/T 908-2008 "Forged Bars - Dimensions, Shape, Weight and Tolerances". Compared with GB/T 908-2008, main changes are as follows.
- maximum nominal diameter of round steel was increased from 400mm to 1000mm; maximum nominal side length of square steel was increased from 400mm to 1000mm; correspondingly added stipulations on allowable size deviation (see Table 1 of this Edition, Table 1 of Edition 2008);
- maximum nominal thickness of flat steel was increased from 160mm to 800mm; maximum nominal width was increased from 300mm to 1500mm; correspondingly added stipulations on allowable size deviation (see Table 2 of this Edition, Table 2 of Edition 2008);
- added stipulations on size, shape and allowable deviation of polished round steel (see Table 1 of this Edition);
- added stipulations on size, shape and allowable deviation of machined steel bar (see Table 3 of this Edition);
- tightened stipulations on curvature of steel bar (see 4.4 of this Edition, 2.5 of Edition 2008);
- added requirements for steel bar delivery with both ends sawing and stipulations on cutting slope (see Table 6 of this Edition);
- deleted marking examples (see Clause 4 of Edition 2008).
1 Scope
This Standard specifies section shape, section size, weight and allowable deviation, length and allowable deviation, shape of forged bars (round steel, square steel, flat steel).
This Standard is applicable to forged round steel of which diameter is 40mm~1000mm, forged square steel of which side length is 40mm~1000mm and flat steel of which thickness is 20mm~800mm, width is 40mm~1500mm.
2 Classification
Forged bars, according to surface state of delivery, are classified into following three categories.
3 Section shape
3.1 Section shapes of forged round steel and flat steel are shown as Figure 1.
4 Section size, weight and allowable deviation
4.1 Size and weight
4.1.1 Sizes and theoretical weights of forged round steel, square steel shall comply with provisions of Table A.1 in Annex A.
4.1.3 Theoretical weights of forged bars that exceed nominal size range specified in Table A.1, Table A.2 are determined by supplier and purchaser via negotiation.
4.2 Allowable size deviation
4.2.1 Hot-forged bars
4.2.1.1 Sizes and allowable deviations of hot-forged wound steel and flat steel shall comply with Table 1. Allowable size deviation groups shall be indicated in corresponding product standards or order contracts. If not specified, perform according to allowable deviation of Group 2.
4.2.1.4 Agreed by supplier and purchaser and indicated in contract, hot-forged bars of medium size unlisted in Table 1 and Table 2 or hot-forged bars of maximum nominal size exceeding Table 1 and Table 2 can be also supplied.
4.2.2 Polished bars
4.2.2.1 Size and allowable deviation of polished round steel of which nominal diameter is 40mm~200mm shall comply with Table 1. Size and allowable deviation of polished round steel of which nominal diameter is greater than 200mm~600mm shall comply with Table 3. Allowable size deviation groups shall be indicated in corresponding product standards or order contracts. If not specified, perform according to allowable deviation of Group 2.
4.2.3 Machined bars
Size and allowable deviation of machined bars shall comply with Table 4.
4.3 Length and allowable deviation
4.3.1 Generally, delivery length for forged bars shall not be less than 1500mm.
4.3.2 Short-foot forged bars of which length is not less than 1000mm are allowed to deliver. But their weights must not exceed 10% of total weight of this batch of delivery.
4.4 Shape
4.4.1 Hot-forged bars
4.4.1.1 Hot-forged round steel
4.4.1.3 Hot-forged flat steel
4.4.1.3.1 Plane curvature of hot-forged flat steel per meter shall not exceed 4mm. Total plane curvature shall not exceed 0.4% of total length.
4.4.1.3.2 Side curvature (sickle bend) per meter of hot-forged flat steel shall not exceed 4mm. Total side curvature (sickle bend) shall not exceed 0.4% of total length.
4.4.2 Polished bars
4.4.2.1 Curvature of polished round steel per meter shall not exceed 4mm. Total curvature shall not exceed 0.4% of total length.
4.4.2.2 Diameter difference of polished round steel at one same section shall not exceed 0.7 times nominal diameter tolerance.
4.4.3 Machined bars
4.4.3.1 Curvature of round steel and square steel per meter shall not exceed 2.5mm. Total curvature shall not exceed 0.25% of total length.
4.4.3.2 Plane curvature and side curvature (sickle bend) of flat steel shall not exceed 2.5mm per meter. Total curvature shall not exceed 0.25% of total length.
4.4.4 Cutting slope of end face
4.4.4.1 Both end faces of forged bars shall be delivered in sawing.
4.4.4.2 Cutting slope of end face of forged bars shall comply with Table 5.
Annex A (normative) Size and theoretical weight of forged bars
A.1 See Table A.1 for sizes and theoretical weights of round steel, square steel of which nominal diameter or side length is 40mm~400mm.
A.2 See Table A.2 for size and theoretical weight of flat steel of which nominal thickness is 20mm~160mm, nominal width is 40mm~300mm. […]
......
This preview omits tables, figures, formulas and parts of the technical clauses. The complete document — 15 pages — is available in the English PDF.
Referenced standards
Cited by
- GB/T 17107-2025Structural steel bars for forgings
- GB/T 44148.1-2024Steel forgings and rolled or forged bars for pressure equipment - Part 1: General requirements
- GB/T 14088-2021Marine halon fire extinguishing system
- GB/T 38589-2020General technical requirements of corrosion-resistant alloy bars, wire rods and wires
- GB/T 38809-2020General specification for low alloy ultra-high strength steels
- GB/T 38820-2020Irradiation-resistant and heat-resistant steels
Similar standards
Editions of GB/T 908
| Edition | Title | Revision | Status |
|---|---|---|---|
| GB/T 908-2019 | Forged bars for dimensions,shape,weight and tolerances | current edition | Current |
| GB/T 908-2008 | Forged bars for dimensions,shape,weight and tolerances | previous edition | Superseded |
This page sells the current edition, GB/T 908-2019. Earlier editions are listed for reference only.
How to Download GB/T 908-2019
- 1
Add to cart
Click "Download PDF" on this page and choose "Buy this standard". You can add more standards before checkout.
- 2
Checkout
Enter your email and billing details. Payment is processed securely by Stripe (cards or bank transfer). Prefer bank details? Request a quotation (min. order $300).
- 3
Instant delivery (0–9 sec)
Delivery is automatic: within seconds of payment you'll receive an email with a secure download link. The link stays valid for 72 hours.
- 4
Invoice included
A tax invoice is attached to the confirmation email. Need a custom invoice? Contact us.
Related Standards
GB/T 10003-2026 — Biaxially oriented polypropylene (BOPP) film
GB/T 10004-2026 — Plastic/Plastic laminated films and pouches for packaging
GB/T 10007-2026 — Rigid cellular plastics - Determination of shear properties
Secure payment via Stripe
Payments accepted
GB/T 908-2019
$125.00