What is the hardness of the 4140 steel bar?

The maximum hardness is 35 HRC, typically close to 30 HRC, ensuring strength and machinability.

Where is the factory located?

Our factory is located in Guanli Road, Fengcheng Industry Zone, Laicheng District, Laiwu, Shandong, China.

What are the main applications for this product?

It is ideal for oil and gas fasteners, petrochemical industrial fasteners, power generation bolts, and pressure vessel studs.

Premium 4140 Steel Bar for Heavy-Duty B7 Threaded Rod

Name: Premium 4140 Steel Bar for Heavy-Duty B7 Threaded Rod
Brand: Shandong Dajin Metal Material Co., Ltd.
SKU: 2182648342

Shandong, ChinaShandong Dajin Metal Material Co., Ltd.

US$1,050.00

2 Tons

Sample price:US$1.00/piece.Request sample

Product profile

Customization

Available

Standard

AISI, ASTM, GB, JIS, ASTM A193 B7 B16,ASTM A320 L7

Technique

Cold Drawn

Model NO.

round bar

Application

B7 L7 B16 Threading Rod

Surface Treatment

Polished

Alloy

Special Use

B7 L7 B16 Studs

Raw Material Grade

4140 B16 304 316 etc.

Quality Level

B7 B8m B16 L7

Ready Stock

Yes

Factory Directly

Yes

Transport Package

Anti-Rust Pacakging

Specification

1/2''-4''

Trademark

dajin

Origin

China

Production Capacity

5000

Key features

High-Precision Tolerance: Precision h9-h11 diameter tolerance ensures optimal threading and minimal tool wear.

Superior Mechanical Consistency: Quenching & Tempering process achieves uniform hardness across the entire bar cross-section.

Full MTR Traceability: Each order includes a Mill Test Report traceable to the original heat number for quality assurance.

Ready Stock Availability: Inventory is kept ready for immediate dispatch to meet urgent production needs.

Professional Export Packaging: Anti-rust treatment and robust packaging protect material integrity during maritime transport.

Factory Direct Supply: Directly from the factory to ensure competitive pricing and quality control.

Versatile Material Grades: Available in 4140, B16, 304, 316, and other custom raw material grades.

Cold Drawn Technique: Cold drawn and centerless ground surface for superior finish and dimensional accuracy.

Company profile

Shandong Dajin Metal Material Co., Ltd.

Shandong, China

Business Type: Manufacturer/FactoryExport Year: 2017-03-04Nearest Port: Qingdao port, Tianjin port, Shanghai portAverage Response Time: ≤6.91hTerms of Payment: LC, T/T, D/P, etc.International Commercial Terms(Incoterms): FOB, CFR, CIF, FAS, DDP, CPT, FCA, EXW

AI-Powered supplier vetting

SummaryShandong Dajin Metal Material Co., Ltd. is identified as a Chinese manufacturer/factory based in Shandong, with four production lines, stated production capacities for several steel-bar categories, and export activity across multiple regions. It holds ISO 9001 and OHSAS/OHSMS 18001 certifications and states that it can supply multiple international standards and customized steel products. The supplier reports export activity since 2017 and that exports represent 51%–70% of total sales. Evidence supports production scale, certification, customization, and international trading capability. However, the provided information does not sufficiently establish after-sales service processes, innovation capability, or financial credibility. Trade records show named buyers and shipments involving Brazil and Pakistan, but the limited transaction evidence does not establish broad or sustained customer performance.

Supplier typeThe supplier is explicitly classified as a Manufacturer/Factory and operates as Shandong Dajin Metal Material Co., Ltd., a limited company located in Shandong, China. This directly supports its status as a manufacturing supplier rather than only a trading entity.

CertificationsThe supplier reports holding ISO 9001 and OHSAS/OHSMS 18001 management-system certifications. These stated certifications provide explicit evidence of quality-management and occupational health and safety systems, although certificate validity dates and scope are not provided.

Production capacityThe supplier reports four production lines, 11–20 years of total R&D-engineer experience, 11–20 quality-control staff, and substantial stated capacities for steel bar, carbon steel round bar, and cold-drawn steel bar. It also reports ready stock of 1,000–1,500 tons for specified products and exports to multiple global regions, providing explicit evidence of meaningful production and fulfillment capability.

Customization capabilityThe supplier explicitly states that it can provide products to GB, American, German, Japanese, industry, and special steel standards and can offer customized services according to customer requirements. Its listed grades and 5 mm–300 mm size range for certain stocked products further support product configuration flexibility.

Client casesTrade records associate the supplier with named buyers in Brazil and Pakistan and show shipments involving steel-related products through Qingdao, including a recorded transaction count of one for one buyer and two for another. These records provide evidence of actual international customer transactions, but the limited number of documented cases does not establish a broad, long-term, or independently verified customer portfolio.