What are the available steel grades?

Grades include St35, St45, St52, E235, E355, 1010, 1045, 4130, 304, 316L, and various low carbon steels.

What are the size ranges for the pipes?

Outer diameters range from 2mm to 60mm, with wall thicknesses from 0.3mm to 10mm and inner diameters up to 12.5mm.

What are the main applications of these pipes?

Applications include automotive powertrain, hydraulic systems, aerospace, heat exchangers, and construction machinery.

GB/T 3639 Small Diameter High Quality Cold Drawn Seamless Steel Pipe

Name: GB/T 3639 Small Diameter High Quality Cold Drawn Seamless Steel Pipe
Brand: Zhangjiagang Chewit International Co., Ltd.
SKU: 2118960435

Jiangsu, ChinaZhangjiagang Chewit International Co., Ltd.

US$1.50-7.00

1,000 kg

Product profile

Customization

Available

Type

Seamless

Technique

Cold Drawn

Model NO.

10 20 16Mn 35 45

Material

Carbon and Alloy

Surface Treatment

Bright Annealing, Black Phosphating, Galvanizing

Usage

Pipeline Transport, Boiler Pipe, Hydraulic/Automobile Pipe, Oil/Gas Drilling, Machinery Industry, Chemical Industry, Mining, Heat Exchanger

Section Shape

Round

Standard

DIN2391, En 10305-1, JIS G3445, ASTM A519

Delivery Condition

Bk, Gbk, Bkw, Bks or Nbk

Steel Grade

St35, St45, St52, E235, E355, 1010, Stkm 11A

Certificate

ISO 9001 Ts16949

Secondary or Not

Non-Secondary

Application

Automotive, Hydraulic System and Precision Device

Transport Package

Plywood Box or Bundles

Specification

OD2-60mm

Trademark

Origin

China

HS Code

7304319000

Key features

Precision Cold Drawn Process: Ensures precise size, low surface roughness, and excellent mechanical performance.

Wide Material Selection: Available in Carbon, Alloy, and Stainless Steel grades including St35, 1010, 304, and 316L.

Multiple Surface Treatments: Options include Bright Annealing, Black Phosphating, and Galvanizing for enhanced durability.

Comprehensive Standard Compliance: Meets DIN, EN, ASTM, JIS, GB, and ISO standards for global application compatibility.

Rigorous Quality Inspection: 100% Eddy Current Test, size check, and chemical analysis with EN 10204 3.1 certificates.

Diverse Application Scope: Ideal for automotive, hydraulic systems, aerospace, machinery, and heat exchangers.

Flexible Delivery Conditions: Available in BK, BKS, GBK, NBK, and other conditions to suit specific project needs.

OEM Service Available: Customized manufacturing solutions available for specific size and grade requirements.

Company profile

Zhangjiagang Chewit International Co., Ltd.

Jiangsu, China

CertifiedBusiness Type: Manufacturer/Factory & Trading Company CertifiedR&D Capacity: OEM Service AvailableExport Year: 2013-08-01 CertifiedNearest Port: shanghaiAverage Response Time: ≤7.52h CertifiedTerms of Payment: LC, T/T

AI-Powered supplier vetting

SummaryZhangjiagang Chewit is a China-based limited trading company established in 2010, with stated precision-tube and steel-forging manufacturing activities. The supplier reports ISO9001:2015 certification, more than 10 production lines, approximately 5,000 tons of annual seamless-steel-pipe productivity, broad export-market coverage, and one-month lead times in both peak and off-peak seasons. Its quality claims include 100% dimensional and surface checks, batch chemical and mechanical testing, and non-destructive testing upon request. Evidence is insufficient to assess after-sales service, financial credibility, and customization capability. Innovation evidence is limited to an associated forging operation reporting 11 authorized patents, while customer evidence consists of one listed buyer and one trade transaction.

Supplier typeThe supplier is identified as a China-based limited company and trade company, with stated manufacturing activities in precision steel tubes and forgings. Its product scope includes seamless, welded, carbon, stainless, hydraulic, cold-drawn, and precision tubes, indicating a specialized steel-product supplier with both trading and manufacturing positioning.

CertificationsThe supplier explicitly reports an ISO9001:2015 management-system certificate. It also describes inspection and industry-related qualifications associated with its forging operation, including API 20B, PED, and classification-society credentials, although the scope and holder of each qualification are not separately specified.

R&D capabilityThe supplier describes advanced production and inspection equipment, precision-tube manufacturing, and a forging operation with 11 authorized patents, including three invention patents. These statements provide explicit but limited evidence of process and product-development capability, mainly linked to the forging operation rather than clearly to the entire supplier entity.

Production capacityThe supplier reports more than 10 production lines, annual seamless-steel-pipe productivity of 5,000 tons, heat-treatment furnaces, inspection equipment, and manufacturing of precision tubes and forgings. The descriptions also cite a 10,000-square-meter tube operation and a substantially larger forging facility, although employee and facility figures are inconsistent across slices and should be verified.

Client casesThe supplier states that it serves wind power, oil and gas, transportation, shipbuilding, and gearbox sectors and has entered the global purchasing system of a major company since 2006. The trade data identifies one buyer and one transaction, so sector references are available but the breadth and depth of verifiable customer cases remain limited.