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العربية alloy steel hex bolts supplier
XZ Fastener supplies alloy steel hex bolts for machinery, construction equipment, steel structures, heavy vehicle assemblies, and high-strength fastening projects. Hex bolts can be supplied according to DIN 931, DIN 933, ISO 4014, ISO 4017, ANSI/ASME B18.2.1, or customer drawings, with Grade 10.9 and Grade 12.9 options commonly requested for demanding joints. Materials, heat treatment, thread length, surface finish, packaging, and inspection documents can be arranged according to order requirement, helping purchasing teams match bolt strength, coating, and dimensional tolerance before production.
Metric and inch sizes, high-strength grades, and project-specific packaging are available upon request.
Quick Specs
What Buyers Should Know Before Sourcing Alloy Steel Hex Bolts
Confirm Full Thread or Partial Thread
Alloy steel hex bolts are ordered as full thread or partial thread depending on joint design. DIN 933 and ISO 4017 are commonly used for full thread metric hex head bolts, while DIN 931 and ISO 4014 are often used for partial thread bolts. This DIN 933 vs DIN 931 guide can help buyers avoid thread-length mistakes.
Do Not Select Grade by Price Alone
Grade 10.9 and Grade 12.9 alloy steel bolts require controlled material and heat treatment. A higher grade is not automatically better for every assembly because preload, mating nut grade, washer hardness, coating friction, and working environment all affect performance.
Common Purchasing Descriptions
Purchasing teams may describe the same product in different ways depending on the drawing, project standard, and market terminology. XZ Fastener can help confirm the correct wording before quotation and production.
- Alloy steel hex bolts Grade 10.9 black oxide, DIN 931 partial thread
- DIN 933 full thread hex bolts Grade 12.9, black finish, metric sizes M5 to M36
- ISO 4017 high tensile hex head bolts with zinc plated or plain oiled finish
- Grade 8.8 carbon steel hex bolts for lower strength projects and general machinery use
- metric hex head bolts packed with matching hex nuts, flat washers, or spring lock washers
- zinc plated DIN 933 bolts, black oxide DIN 933 bolts, and hot dip galvanized DIN 933 bolts for different corrosion and appearance requirements
For buyers comparing high-strength classes, XZ Fastener provides a practical reference on 8.8, 10.9, and 12.9 bolt mechanical properties.
Detailed Specifications Table
| Item | Common Options | Purchasing Notes |
|---|---|---|
| Product Name | Alloy steel hex bolts | Also called high tensile hex bolts, hex head bolts, or hex cap screws depending on market |
| Standards | DIN 931, DIN 933, ISO 4014, ISO 4017, ANSI/ASME B18.2.1 | Confirm the standard because head dimensions, thread length, and tolerance may differ |
| Size Range | M5 to M36, inch sizes available upon request | Diameter, length, thread pitch, and thread length should be listed clearly |
| Thread Type | Metric coarse, metric fine, UNC, UNF | Pitch affects nut fit and installation; do not assume pitch from diameter alone |
| Material | 40Cr, 35CrMo, SCM435, 4140, or equivalent alloy steel | Material can be selected according to strength class and heat treatment requirement |
| Strength Class | 10.9, 12.9, or drawing-specified class | Mechanical property requirements should be confirmed before production |
| Surface Finish | Black oxide, zinc plated, hot dip galvanized, zinc flake, phosphate, plain oiled | Finish should match corrosion exposure, assembly friction, and appearance requirement |
| Matching Parts | Hex nuts, heavy hex nuts, flat washers, hardened washers, spring lock washers | Nut grade and washer hardness should match bolt strength and joint design |
| Inspection | Dimension, thread, hardness, tensile, proof load, coating thickness, visual check | Inspection reports are available upon request when specified before order confirmation |
| Packaging | Cartons, small boxes, bags, pallets, customer label, mixed size kits | Export packing and private labels can be arranged according to order requirement |
Material and Grade Explanation
Alloy steel hex bolts are selected when the assembly needs higher tensile strength and better hardenability than standard carbon steel grades. Materials such as 40Cr, 35CrMo, SCM435, or 4140 can be heat treated to reach Grade 10.9 or Grade 12.9 performance, depending on the standard and order requirement.
For high-load joints, buyers should confirm bolt grade, nut grade, washer type, tightening method, and whether the coating changes friction behavior. The article on ISO 898-1 bolt grades and mechanical properties is useful when checking metric bolt class requirements.
Surface Finish Selection Guide
Black Oxide
Common for alloy steel hex bolts used in machinery and indoor equipment. Usually supplied with oil for short-term corrosion protection and a dark technical appearance.
Zinc Plated
Suitable for general indoor and light-duty corrosion resistance. Coating thickness, passivation color, and hydrogen embrittlement risk should be considered for high-strength bolts.
Hot Dip Galvanized
Often used for outdoor steel structures and construction assemblies. Thread allowance and matching nut fit should be confirmed because the coating is thicker.
Zinc Flake
Available upon request for higher corrosion resistance where high-strength bolts need a non-electrolytic coating system.
Phosphate and Oil
Used when a dark finish and controlled friction behavior are needed in machinery assembly or heavy equipment applications.
Plain Oiled
Suitable for protected storage or buyer-controlled secondary treatment. Oil type and packing method can be discussed before shipment.
For coating comparison, buyers can review the fastener coating guide and the guide to zinc plated vs hot dip galvanized bolts.
Manufacturing and Quality Control
Production control for alloy steel hex bolts should cover raw material selection, cold heading or hot forging, thread rolling, heat treatment, surface finishing, inspection, and packing. Key inspection points include head dimensions, shank diameter, thread pitch, length, hardness, surface condition, coating thickness, and thread fit.
For order control, buyers can specify inspection documents in advance. XZ Fastener shares more detail in its guide to fastener quality control during manufacturing and go/no-go thread gauge testing.
Applications
- Heavy machinery, production equipment, and maintenance assemblies
- Steel structures, platforms, brackets, and support frames
- Automotive, trailer, agricultural machinery, and off-road equipment
- Wind power, mining equipment, and high-load industrial joints
- Construction fastener packages with nuts and washers
- OEM production lines requiring stable bolt grade and packaging
- Replacement projects where DIN, ISO, ANSI, or drawing dimensions must match
- Outdoor assemblies requiring zinc flake, HDG, or specified corrosion protection
How to Get a Faster Quotation
To help XZ Fastener prepare an accurate quotation, please send the standard or drawing, size list, diameter, length, thread pitch, full thread or partial thread requirement, grade, finish, quantity, packaging method, and inspection requirements. If bolts need to be supplied with nuts and washers, include matching part details in the same inquiry.
For urgent projects, use the request a quote page or contact XZ Fastener with drawings, photos, current supplier part numbers, or project specifications.
FAQ
Can alloy steel hex bolts be supplied in Grade 12.9?
Yes. Grade 12.9 alloy steel hex bolts can be supplied for high-strength assemblies when the required standard, size, finish, and inspection requirements are confirmed before production.
What is the difference between DIN 931 and DIN 933 alloy steel hex bolts?
DIN 931 is generally used for partial thread hex bolts, while DIN 933 is used for full thread hex bolts. Buyers should confirm the required thread length from the drawing or assembly condition.
Can high-strength alloy steel bolts be zinc plated?
Zinc plating can be supplied, but high-strength bolts require careful process control because hydrogen embrittlement risk must be considered. Alternative coatings such as zinc flake may be discussed for certain applications.
Do alloy steel hex bolts need matching high-strength nuts?
In many high-load assemblies, bolt grade should be matched with suitable nut grade and washer hardness. The final selection should follow the drawing, project specification, or engineering requirement.
Can XZ Fastener supply bolts according to customer drawings?
Yes. Non-standard dimensions, special thread length, specified material, custom coating, and project packaging can be discussed when drawings, samples, or detailed specifications are provided.
What inspection documents can be requested with alloy steel hex bolts?
Common documents include dimension inspection, hardness check, coating thickness report, thread inspection, and packaging check. Additional mechanical test reports can be discussed before order confirmation.
Send Your Alloy Steel Hex Bolt Inquiry
For a faster quotation, please send your size list, required finish, quantity, packaging method, and inspection requirements. Drawings, grade requirements, coating expectations, and matching nut or washer details help confirm the correct alloy steel hex bolts before production.
Request a Quote from XZ Fastener