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العربية black oxide hex bolts supplier
XZ Fastener supplies black oxide hex bolts for machinery, tooling, equipment frames, automotive repair, brackets, fixtures, and industrial maintenance assemblies. Bolts can be supplied according to DIN 931, DIN 933, ISO 4014, ISO 4017, ANSI/ASME B18.2.1, or customer drawings, with full thread and partial thread options available. Carbon steel, alloy steel, Grade 8.8, 10.9, and 12.9 requirements can be discussed according to order requirement, with black oxide finish, oil protection, packaging, and inspection details confirmed before production.
Black oxide bolts can be supplied with matching nuts, flat washers, spring washers, and project packaging.
Quick Specs
What Buyers Should Know Before Sourcing Black Oxide Hex Bolts
Black Oxide Is Mainly a Controlled Appearance Finish
Black oxide provides a dark surface and light corrosion resistance when used with oil, but it should not be selected as a heavy outdoor coating. It is commonly used for machinery, tooling, and protected equipment assemblies. Buyers comparing finishes can review XZ Fastener’s black oxide vs zinc plated fasteners guide.
Confirm Full Thread, Partial Thread, and Grade
Black oxide finish does not define the bolt standard or strength. DIN 933 and ISO 4017 are commonly used for full thread bolts, while DIN 931 and ISO 4014 are used for partial thread bolts. This DIN 933 vs DIN 931 guide explains the practical difference.
Common Purchasing Descriptions
Black oxide hex bolt inquiries should include standard, size, grade, thread length, finish, oil protection, quantity, and packing method. Buyers often use the following descriptions in RFQs and purchase orders.
- black oxide DIN 933 bolts, full thread, carbon steel, Grade 8.8
- DIN 931 black oxide hex bolts, partial thread, Grade 10.9 or Grade 12.9
- Grade 8.8 carbon steel hex bolts with black oxide and oil protection
- metric hex head bolts for machinery, fixtures, and equipment frames
- DIN 933 full thread hex bolts packed with black oxide hex nuts and flat washers
- zinc plated DIN 933 bolts and hot dip galvanized DIN 933 bolts as alternative finish options for different corrosion environments
For a product reference, see XZ Fastener’s DIN 933 black oxide hex bolts page.
Detailed Specifications Table
| Item | Common Options | Purchasing Notes |
|---|---|---|
| Product Name | Black oxide hex bolts | Also called black hex head bolts, black oxide hex cap screws, or black finish hex bolts |
| 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 M64, inch sizes available upon request | Diameter, length, pitch, and thread length should be listed clearly |
| Thread Type | Metric coarse, metric fine, UNC, UNF, full thread, partial thread | Thread pitch should match nuts, tapped holes, or existing inventory |
| Material | Low carbon steel, medium carbon steel, alloy steel, 40Cr, SCM435 | Material should match strength grade, load requirement, and heat treatment needs |
| Strength Class | 4.8, 8.8, 10.9, 12.9, or drawing-specified class | Higher grades should be confirmed with hardness, tensile, and inspection requirements |
| Finish | Black oxide, black oxide with oil, black phosphate upon request | Oil protection, appearance, and storage method should be discussed before shipment |
| Matching Parts | Black oxide hex nuts, flat washers, spring washers, flange nuts | Matching parts should be confirmed with the same finish when visual consistency matters |
| Inspection | Dimension, thread, hardness, tensile where required, visual finish, oil coverage | Inspection reports are available upon request when specified before order confirmation |
| Packaging | Bulk cartons, small boxes, bags, pallets, private labels, mixed kits | Packaging can be arranged according to order requirement and warehouse handling needs |
Material and Grade Explanation
Black oxide hex bolts are commonly produced from carbon steel or alloy steel because these materials can be formed, heat treated, and finished with a dark oxide surface. Grade 8.8 is frequently used for general machinery assemblies, while Grade 10.9 and Grade 12.9 may be specified for higher strength applications where the assembly design supports the grade.
When ordering high-strength black oxide bolts, buyers should confirm bolt grade, nut grade, washer type, tightening method, and whether oil protection is required for storage. For grade selection, XZ Fastener provides a guide to hex bolt sizes, grades, and installation.
Surface Finish Selection Guide
Black Oxide with Oil
Common for machinery and tooling applications where a dark appearance and short-term storage protection are required.
Black Oxide Dry Finish
Can be discussed when oil residue is not acceptable, but corrosion protection will be lower without oil or additional protection.
Black Phosphate Alternative
Available upon request for selected fasteners where a black finish and different surface behavior are required.
Zinc Plated Alternative
Used when buyers need a brighter appearance and moderate indoor corrosion resistance instead of a dark finish.
Hot Dip Galvanized Alternative
Selected for outdoor environments where thicker zinc coating is needed, with thread fit and matching nuts confirmed in advance.
Special Coating
Zinc flake, PTFE, or other coatings can be discussed when corrosion resistance or friction behavior must be specified.
For broader finish comparison, buyers can review the fastener coating guide.
Manufacturing and Quality Control
Production control for black oxide hex bolts may include raw material inspection, cutting, cold heading or hot forging, thread rolling, heat treatment where required, black oxide finishing, oiling, sorting, inspection, and packing. Key checks include head dimensions, length, thread fit, hardness, finish color, surface condition, oil coverage, and packaging label accuracy.
For inspection planning, XZ Fastener’s guide to fastener quality control during manufacturing and go/no-go thread gauge testing can help buyers define acceptance checks.
Applications
- Machine tools, fixtures, equipment frames, and maintenance assemblies
- Automotive repair, brackets, guards, housings, and support plates
- Indoor machinery where a dark technical appearance is required
- Distributor stock programs for Grade 8.8, 10.9, and 12.9 black bolts
- Bolt, nut, and washer kits with matching black oxide finish
- OEM assembly lines requiring stable appearance and packing control
- Replacement projects where DIN, ISO, or ANSI dimensions must match
- Protected indoor equipment where heavy outdoor coating is not required
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, black oxide finish requirement, oil protection requirement, quantity, packaging method, and inspection requirements. If bolts need matching nuts and washers, include those details in the same inquiry.
For a structured inquiry, use the request a quote page or contact XZ Fastener with drawings, photos, samples, or current supplier part numbers.
FAQ
What is black oxide finish used for on hex bolts?
Black oxide finish is used for dark appearance, mild surface protection with oil, and machinery or tooling assemblies where a black finish is preferred.
Are black oxide hex bolts suitable for outdoor use?
Black oxide bolts are usually better for indoor or protected environments. For outdoor exposure, hot dip galvanized, zinc flake, stainless steel, or another specified coating may be more suitable.
Can black oxide hex bolts be supplied in Grade 8.8?
Yes. Grade 8.8 carbon steel hex bolts can be supplied with black oxide finish when the standard, size, finish, and inspection requirements are confirmed before production.
Can black oxide bolts be supplied with oil protection?
Yes. Oil protection is commonly used with black oxide bolts to improve short-term corrosion resistance during storage and transport.
Can black oxide bolts be packed with nuts and washers?
Yes. Black oxide hex bolts can be supplied with matching hex nuts, flat washers, spring washers, and custom kit packaging according to order requirement.
What information should be included in a black oxide bolt RFQ?
Please include standard, size list, grade, thread type, finish requirement, oil protection, quantity, packaging method, and inspection requirements. Drawings or samples are helpful for non-standard items.
Send Your Black Oxide Hex Bolt Inquiry
For a faster quotation, please send your size list, finish, quantity, packaging method, and inspection requirements. Drawings, bolt grade, thread pitch, oil protection, matching nut or washer details, and label format help confirm the correct black oxide hex bolts before production.
Request a Quote from XZ Fastener