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العربية black oxide socket head cap screws manufacturer
XZ Fastener supplies black oxide socket head cap screws for machinery, tooling, automation equipment, and assemblies that need a low-profile cylindrical head with internal hex drive. These screws are commonly requested to DIN 912 or ISO 4762, with metric coarse threads, full thread or partial thread according to size, and alloy steel strength classes such as 8.8, 10.9, or 12.9 according to order requirement. Black oxide provides a dark appearance and light corrosion resistance when oiled, making it suitable for controlled indoor environments. For purchasing teams, XZ Fastener can quote standard sizes, custom lengths, matching washers or nuts, and inspection documents when required.
Typical RFQs include standard, diameter, length, pitch, strength class, finish, quantity, packaging, and inspection requirements.
Quick Specs
What Buyers Should Know Before Sourcing Black Oxide Socket Head Cap Screws
Socket head cap screws are selected when the assembly needs high clamp force, compact head diameter, and hex socket drive access. XZ Fastener can support standard hex socket head cap screws as well as custom fasteners made according to drawing or sample requirements.
Before placing an order, buyers should confirm the standard, thread pitch, length measurement rule, head diameter, socket depth, strength class, and surface finish. For mixed assemblies, the technical comparison of hex bolts and socket head cap screws can help clarify which drive style is suitable for installation space and service load.
Procurement Notes
- Black oxide is generally chosen for indoor equipment, tooling, and controlled workshop conditions.
- Oil after black oxide treatment helps improve short-term rust resistance during storage and shipping.
- High-strength grades should be checked carefully for hardness, thread fit, and hydrogen embrittlement risk when electroplated alternatives are considered.
- Packaging can be arranged by bulk carton, small box, pallet, label, or buyer-specific requirement.
Common Purchasing Descriptions
Black oxide socket head cap screws may appear in RFQs under several descriptions, including DIN 912 cap screws, ISO 4762 socket cap screws, Allen head cap screws, hex socket machine screws, alloy steel socket bolts, and black finish socket screws. Buyers often combine them with other fastener products for project-based procurement.
- DIN 912 black oxide socket head cap screws, M3-M36, class 12.9
- ISO 4762 alloy steel socket cap screws, metric coarse thread
- Hex socket head cap screws with black oxide and oil finish
- Machine screws for molds, fixtures, CNC equipment, and automation machinery
- Related bolt lines: DIN 933 full thread hex bolts, Grade 8.8 carbon steel hex bolts, metric hex head bolts, zinc plated DIN 933 bolts, black oxide DIN 933 bolts, and hot dip galvanized DIN 933 bolts
Detailed Specifications Table
| Предмет | Common Options | Buyer Confirmation Points |
|---|---|---|
| Product type | Socket head cap screw, hex socket cap screw, Allen head cap screw | Confirm head style, socket drive, and whether the part must match DIN 912 or ISO 4762. |
| Size range | Metric sizes such as M3, M4, M5, M6, M8, M10, M12, M16, M20 and above | Send diameter, length, pitch, and full size list for accurate pricing. |
| Thread | Metric coarse thread; fine thread available upon request | Confirm pitch and thread tolerance if the screw fits an existing tapped hole. |
| Length | Standard lengths or custom lengths according to order requirement | Length is usually measured from under the head to the screw end. |
| Материал | Carbon steel, alloy steel, stainless steel for special corrosion requirements | Confirm material grade and mechanical property requirement before production. |
| Strength class | 8.8, 10.9, 12.9 are common for steel socket head cap screws | Match strength class to load, tightening method, and mating thread material. |
| Finish | Black oxide with oil, plain, zinc plated, nickel plated, or custom coating | Black oxide is not a heavy corrosion-protection finish; confirm service environment. |
| Inspection | Dimensional check, thread gauge, hardness, surface appearance, packing check | Special inspection reports can be prepared when requested before order confirmation. |
Material and Grade Explanation
Most black oxide socket head cap screws are supplied in medium carbon steel or alloy steel because these materials can reach higher mechanical strength after heat treatment. Class 8.8 is suitable for general machinery fastening, while 10.9 and 12.9 are used where higher tensile strength and clamp load are required.
For stainless assemblies, buyers may choose A2 or A4 stainless socket screws instead of black oxide steel screws. For high-strength steel screws, hardness control and thread rolling quality are important because the internal hex drive is often used in applications with controlled tightening torque.
Grade Selection Tips
- Use class 8.8 when normal machinery strength is sufficient.
- Use class 10.9 or 12.9 only when the design and tapped material can support higher tightening load.
- Confirm whether the mating thread is steel, cast iron, aluminum, or an insert.
- Ask for hardness or mechanical test requirements before production if the assembly is critical.
Surface Finish Selection Guide
Black Oxide
Black oxide gives a dark appearance and dimensional stability with minimal coating build-up. It is normally used with oil and is suitable for indoor machinery, fixtures, and tooling storage.
Zinc Plating
Zinc plating provides brighter appearance and better corrosion resistance than black oxide for many general-purpose indoor and light-duty applications. See this black oxide vs zinc plated fasteners guide for selection considerations.
Other Coatings
For higher corrosion requirements, buyers may review zinc flake, Dacromet, Geomet, PTFE, or hot dip galvanized options where suitable. The fastener coating guide explains common coating choices.
Manufacturing and Quality Control
Socket head cap screws are commonly produced through wire preparation, cold heading, socket forming, thread rolling, heat treatment, surface finishing, inspection, and packing. Process control is important because head height, socket depth, thread accuracy, hardness, and surface condition all affect assembly performance.
XZ Fastener can arrange checks according to order requirement, including dimensional inspection, hardness testing, surface appearance review, and go/no-go thread gauge testing. Buyers who need more detail can also review the fastener quality control process before confirming an order.
Приложения
Typical Industrial Uses
- Machine tools, CNC equipment, molds, and fixtures
- Automation equipment, robot bases, conveyors, and guide rails
- Motors, pumps, gearboxes, and mechanical housings
- Precision assemblies where external wrench clearance is limited
When to Choose Another Finish
- Use zinc plated or zinc flake fasteners when corrosion resistance is more important than dark appearance.
- Use stainless steel when the assembly is exposed to moisture, chemicals, or washdown conditions.
- Use plain or lightly oiled finish only when parts will be installed quickly in a controlled environment.
- Confirm coating thickness when thread fit is sensitive.
How to Get a Faster Quotation
To receive a practical quotation for black oxide socket head cap screws, send a complete size list with diameter, length, pitch, standard, strength class, finish, quantity, packaging method, delivery destination, and inspection requirements. Drawings or samples are helpful when the screw has non-standard length, shoulder, drilled hole, special socket depth, or custom head dimension.
If you are preparing a project list with screws, bolts, nuts, and washers, send the full list together so XZ Fastener can check matching standards, material compatibility, finish consistency, and packing details before quotation.
Часто задаваемые вопросы
Can XZ Fastener supply DIN 912 or ISO 4762 black oxide socket head cap screws?
Yes. DIN 912 and ISO 4762 socket head cap screws can be supplied according to size, material, strength class, finish, and order quantity requirements.
Is black oxide suitable for outdoor use?
Black oxide is mainly recommended for indoor or controlled environments. For outdoor exposure, zinc plated, zinc flake, hot dip galvanized, stainless steel, or other corrosion-resistant options should be reviewed.
What strength classes are common for black oxide socket head cap screws?
Common steel strength classes include 8.8, 10.9, and 12.9. The correct choice depends on assembly load, tightening method, mating thread material, and engineering requirement.
Can custom sizes or non-standard socket screws be supplied?
Custom sizes can be reviewed according to drawing, sample, or detailed specification. Buyers should provide dimensions, tolerances, material, finish, quantity, and inspection requirements.
What information should be included in an RFQ?
Please include standard, diameter, length, thread pitch, strength class, material, finish, quantity, packaging, destination, and inspection requirements. A drawing is recommended for non-standard screws.
Can inspection documents be provided with the shipment?
Inspection documents can be prepared according to order requirement. Common checks include dimensions, thread fit, hardness, surface appearance, quantity, labeling, and packing condition.
Send Your Socket Head Cap Screw RFQ
For a faster quotation, send your size list, required finish, quantity, packaging method, delivery destination, and inspection requirements. XZ Fastener can review black oxide socket head cap screws together with related bolts, nuts, washers, and custom fasteners according to your purchasing plan.