12.9 Grade Black Oxide Allen Head Socket Cap Screws High Strength Hexagon Socket Bolts08.jpg

12.9 Grade Black Oxide Allen Head Socket Cap Screws High Strength Hexagon Socket Bolts09.jpg

12.9 Grade Black Oxide Allen Head Socket Cap Screws High Strength Hexagon Socket Bolts10.jpg

12.9 Grade Black Oxide Allen Head Socket Cap Screws High Strength Hexagon Socket Bolts11.jpg

12.9 Grade Black Oxide Allen Head Socket Cap Screws High Strength Hexagon Socket Bolts12.jpg

12.9 Grade Black Oxide Allen Head Socket Cap Screws High Strength Hexagon Socket Bolts DIN 912 for Machinery & Automotive

Name: 12.9 Grade Socket Cap Screw (Allen Head Bolt）
Material: SCM435/40Cr alloy steel
Standards: GB/T 70.1, DIN 912, ISO 4762, ANSI/ASME B18.3
Grade: .12.9 (High-strength alloy steel, tensile strength ≥1200MPa, yield strength ≥1080MPa)
Specifications: M2-M36 (customizable)
Surface Treatment: Blackening/Oxidation (anti-oxidation, improves surface hardness, reduces friction coefficient), nickel plating, zinc plating, Dacromet treatment
Design Features: High-strength alloy steel material, hexagonal drive structure, Cylindrical head design, precision knurled texture, high-precision full-thread design
Applications: Machinery manufacturing, automotive industry, construction machinery, industrial equipment, precision instruments
Delivery Time: 15-30 days after receiving advance payment
Origin: China
Brand: JGD
Minimum Order Quantity: 10,000 pieces, negotiable
Samples: Available
Packaging: Boxed/Bulk/Pallet or customized packaging
OEM: Available

304 Stainless Steel Cross Recessed Countersunk Head Self-Tapping Screws01

304 Stainless Steel Cross Recessed Countersunk Head Self-Tapping Screws02

Key Features

Our 12.9 grade socket cap screws are made of SCM435/40Cr alloy steel with tensile strength ≥1200MPa and yield strength ≥1080MPa. The hex socket drive accepts standard hex keys for confined spaces; the cylindrical head + precision knurling allows finger pre‑tightening. Black oxide treatment increases surface hardness, reduces friction coefficient, and provides anti‑rust protection. Size range covers M2 to M36, with full or partial threads. Suitable for machinery, automotive chassis, heavy equipment, and precision instruments. Installation: tighten with a hex key to the recommended torque.

304 Stainless Steel Cross Recessed Countersunk Head Self-Tapping Screws03

304 Stainless Steel Cross Recessed Countersunk Head Self-Tapping Screws04

Precision Manufacturing Process

We use multi‑station cold heading to form the head and shank in one stroke, ensuring hex socket concentricity ≤0.1mm. Precision thread rolling (carbide dies, 6g accuracy) produces full threads, increasing fatigue strength by >30% over cutting. Controlled‑atmosphere mesh belt furnace quenching + low‑temperature tempering yields tempered martensite (HRC 39-44). Black oxide treatment (hot alkaline blackening) with oil sealing. Each batch is sampled for tensile test (≥1200MPa), hardness, and hydrogen embrittlement test (48‑hour delayed fracture test).

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304 Stainless Steel Cross Recessed Countersunk Head Self-Tapping Screws06

Transparency & Customization

Each bag of screws comes with a full inspection report (material spectroscopy, hardness, tensile strength, thread go/no‑go rate). The package QR code traces back to the cold heading machine, heat treatment batch, and black oxide line. Our website shows metallographic structure images and failure cases (e.g., hydrogen embrittlement fracture, over‑torque breakage).

Customization options: Accept non‑standard length, head diameter, and hex socket across‑flats size. Thread tolerances can be 6g or 5g6g. Surface treatment can be electro‑galvanized (blue/white or yellow zinc), nickel‑plated, or Dacromet (salt spray ≥1000h). Mixed standards (DIN/ISO/GB/ANSI) supported. Anti‑rust oil sealing or vacuum packaging available.

304 Stainless Steel Cross Recessed Countersunk Head Self-Tapping Screws08

304 Stainless Steel Cross Recessed Countersunk Head Self-Tapping Screws07

Grade 12.9 · Alloy Steel · Black Oxide

12.9 grade high-strength socket cap screw, SCM435 alloy steel, tensile strength ≥1200MPa, DIN 912. Black oxide coating reduces friction and prevents oxidation. Hex socket drive saves installation space. Used in machinery, automotive chassis, engineering equipment. Sizes M2-M36 available.

product details

JGD Service

Manufacturing Process

• Multi Station Cold Heading Technology

• Intelligent Heat Treatment System

• Micron-Level Thread Rolling Process

• Fully Automatic Optical Sorting

• Environmentally Friendly Surface Treatment Line

• Metallographic And Mechanical Joint Laboratory

Quality Control System

• Raw Material Source Locking

• Furnace Number Batch Full Traceability

• Third Party Material Certification

• Process Parameters Open And Transparent

• Salt Spray Test Real Time Monitoring

• International Standard Compliance Declaration

Flexible Customization Capability

• Customizable head/slot Shapes

• Extreme Application Of Special Materials

• Breakthroughs In Extra Large/Long Specifications

• Integrated Assembly Of Components

• Customizable Surface Treatment Colors

• Personalized Packaging And Labeling

Technical Service

• On-Site Failure Analysis

• Selection Calculation And BOM Optimization

• Installation Tool Selection Guidance

• Inventory Management (VMI) Trusteeship

• Free Sample Making And Testing

• International Standard Translation And Interpretation

Black Oxide for Rust & Corrosion Resistance

Made of SCM435/40Cr alloy steel with black oxide finishing, the surface forms a magnetic iron oxide film that effectively blocks humid air and mild corrosive media. Although not as salt-spray resistant as stainless steel, it prevents red rust in dry indoor environments, mechanical assembly, and engine compartments. The oxide layer also increases surface hardness and reduces fretting wear, with no hydrogen embrittlement risk – ideal for high-strength fastening.

Ultra-High Strength Metal for Anti-Loosening

Grade 12.9 offers tensile strength ≥1200MPa and yield strength ≥1080MPa, far exceeding stainless steel or Grade 8.8 bolts. When tightened, the hex socket drive transmits high torque, creating enormous clamping force and significantly increasing thread friction. Even under severe vibration, impact, or cyclic loads (e.g., construction machinery, racing chassis), the bolt remains secure. Metal material never ages, ensuring lasting locking performance.

Long Service Life with High Wear Resistance

The black oxide layer provides self-lubricating properties, reducing thread friction and minimizing galling or cold welding during assembly. The cylindrical head and fine knurling enable hand-tightening without tool slippage or surface damage. Proven in fatigue tests, the head-to-shank fillet and thread root withstand millions of cycles without cracking. Compared to common zinc-plated bolts, this product offers superior wear resistance, longer replacement intervals, and lower maintenance costs.

Application Scenarios

High-Quality 12.9 Grade Socket Cap Screw Display

Precision Fastening, Engineered for the Future – Chengdu Jingguda Trading Co., Ltd., Your Trusted High-Quality Fastener Expert

Chengdu Jingguda Trading Co., Ltd. is a professional fastener manufacturer integrating R&D, production, and sales. We specialize in high-precision, high-strength bolts, nuts, washers, and non-standard customized fasteners, covering international standards such as GB, DIN, ISO, ANSI, and ASME. Equipped with multi-station cold heading machines, high-speed thread rolling machines, fully automated heat treatment lines, and surface treatment equipment, we also operate an in-house laboratory featuring spectrometers, hardness testers, tensile testing machines, and salt spray testers to ensure strict quality control from raw materials to finished products. Our products are widely used in industrial machinery, renewable energy, automotive manufacturing, rail transportation, and more, known for their precision, corrosion resistance, and durability. Committed to “Fast Delivery, Professional Support,” we provide one-on-one customized solutions and efficient logistics, striving to be your ideal partner for reliable connections.

Industrial Capabilities

• Factory Area: 8,000 square meters

• Certifications: ISO, IATF, CE, RoHS, JIS, ASTM

• Manufacturing : 70+ internationally advanced production lines

• Testing: 30+ sets of precision quality testing equipment

• Annual Output: Up to 50,000,000 tons

From Raw Materials to Completed Items

Closed-loop manufacturing from raw materials to final products is made possible by our factory's fully automated production lines for cold heading, precision thread rolling, controlled-atmosphere heat treatment, and eco-friendly surface finishing. Each fastener satisfies strict requirements for strength, precision, and surface quality due to inline optical sorting and a digital MES. You promise the greatest fasteners—reliable, effective, and environmentally responsible.

Lab for Innovation:

Are you currently engaged in any projects? Now let's go on. Talent and hard work drive our development, and we're constantly searching for fresh ideas. Are you engaged in a project? Now let's go on.

From "Pain Point Diagnosis" to "Customized Implementation" across the whole collaborative research and development process

Traditional parts are not all we provide. Our multicultural engineering staff actively participates in your project from the outset. In order to ensure that creative concepts are swiftly converted into workable solutions that lower overall lifespan costs, we carefully evaluate the application environment and create solutions in the lab, fully integrating technology and application.

Integrated Verification System: Assuring Innovation with "Test Data"

The drawing board is not the end of the creative process. Through our internal technical center, we provide one-stop verification for anything from corrosion testing to prototype creation. Through thorough simulated working condition tests, we use empirical data to confirm the performance stability of tailored solutions. This significantly reduces project risks and achieves truly reliable cost reduction and efficiency improvement.

Rapid Service Response

Strategically plan production using digital quality control and agile supply chains to reduce bulk order delivery time by 30% after confirmation; use self-developed molds and flexible manufacturing lines to complete sample and delivery within 7 days. You may be able to take advantage of market opportunities for both standard bolts and custom-shaped parts with our "Demand-Solution-Sampling-Production" closed-loop system.