1.Introduction
In today’s fast-paced industrial world, fastening systems must not only be strong but also efficient. Among the many types of screws available, the hex combination screw stands out due to its practical design and time-saving assembly features.

Combining a hexagonal head, a cross recess, and pre-assembled washers, this type of screw is widely used in electronics, automotive panels, electrical cabinets, and other applications where vibration resistance and speed are crucial.

In this article, we’ll walk you through the entire manufacturing process of hex combination screws—from raw material selection to cold heading, threading, washer assembly, surface treatment, and final inspection. Whether you’re a buyer, distributor, or OEM looking to understand what goes into a reliable combination screw, this guide covers it all.

2.Materials Used in Hex Combination Screw Manufacturing
The quality of a screw begins with its raw material. Depending on the application and performance needs, we select different steel grades and types.

Common Materials:
#Carbon Steel (Low and Medium) – Suitable for general-purpose fastening, available in Grade 4.8 or 8.8.
#Alloy Steel – Offers higher tensile strength, typically for Grade 10.9 or 12.9 applications.
#Stainless Steel (304 / 316) – Excellent corrosion resistance, ideal for marine and outdoor use.

Material Certifications:
We only use material from certified mills, with mill test reports (MTRs) to ensure chemical and mechanical property compliance.

3. Key Features of Hex Combination Screws
What makes a hex combination screw different?

#. Dual Drive Head
Hex head enables high-torque installation using a wrench.
Cross (Philips) recess allows for quicker installation with power tools.

#. Pre-Assembled Washers
Saves labor time on production lines.
Provides better load distribution and anti-loosening performance.

Washer types:
#Spring washer (DIN 127)
#Flat washer (DIN 125)

Tooth lock washer (for anti-vibration)

4. One-Step Fastening
By integrating multiple parts into one fastener, the combination screw streamlines installation, reduces error, and improves efficiency.

5. Manufacturing Process Overview
The production of hex combination screws is highly systematic and requires strict process control. Below is a step-by-step explanation.

Step 1: Wire Drawing
Steel rods are drawn into the required diameter, cleaned, and coated to prepare for cold forming.

Step 2: Cold Heading
The screw blank is formed.
Machines create the hex head and cross recess in one press cycle.
Precision tooling ensures clean slot formation without cracks or burrs.

Step 3: Thread Rolling
Threads are not cut but rolled using hardened dies.
This strengthens the thread structure and improves fatigue resistance.
Common thread types:
Metric Coarse (e.g. M5 x 0.8)
UNC/UNF for American markets

Step 4: Washer Assembly
Washers are automatically fed and attached to each screw using high-speed assembly equipment.
Proper orientation and tightness are verified inline.
Step 5: Heat Treatment
For carbon and alloy steel screws:
Heat treated to meet required hardness and tensile strength.
Controlled atmosphere furnaces prevent decarburization.

Step 6: Surface Coating
The finish affects corrosion resistance and appearance. We offer:
#Zinc plating (blue, white, yellow)
#Black oxide
#Nickel plating
#Trivalent chrome (ROHS compliant)

Step 7: Quality Control
Dimensional checks using GO/NO-GO gauges
Torque and pull-out testing
Visual inspection for head defects and washer position

6. Technical Standards and Specifications
Our hex combination screws conform to multiple international standards. These include:

#DIN 6900 – German standard for combination fasteners
#JIS B1188 – Japanese Industrial Standard
#ISO 7045 – International standard for machine screws
#Non-standard OEM – We also produce to customer drawings and specifications

Typical Sizes Available:
M4 x 10mm to M8 x 50mm
Custom thread pitch and washer configurations
Tolerances:
Thread tolerance: 6g
Head diameter: ±0.15mm
Washer tightness: mechanically locked, no free play

7. Packaging and Logistics
We understand that industrial clients have specific packaging needs. We offer:

Bulk packaging in cartons or woven bags
Small boxes with labels, suitable for retail or kit assembly
Palletized export shipments
Barcode scanning, weight printing, and QR code labeling available on request
We export large volumes of hex combination screws to North America, Southeast Asia, and the Middle East, using reliable freight forwarding services for timely delivery.

8. Applications and Industry Use Cases
Combination screws are designed for quick installation and high performance. They are used in:

#Electrical enclosures and distribution boxes
#Automotive interior fastening
#Household appliances (e.g. washing machines, air conditioners)
#Solar panel mounting brackets
#Sheet metal assembly and grounding
Their time-saving feature makes them ideal for mass production environments where efficiency is essential.

9. Why Choose Us as Your Supplier
As a manufacturer based in Zhongshan, China, we offer complete control over the production process. This allows us to deliver:

#Consistent Quality – Every batch is tested before shipping
#OEM & Customization Support – Based on your drawing or sample
#Flexible Order Quantities – From trial batches to container loads
#Quick Lead Times – Most standard models ready in 15–20 days
#Competitive Pricing – Direct-from-factory pricing with no middleman

We currently serve clients in USA, Vietnam, Malaysia, Thailand, and Mexico, providing technical support and stable supply.

10. Video: Hex Combination Screw Production in Action
We’ve prepared a behind-the-scenes video to show you how these screws are made—from raw material to finished product（contact us for more video）.

What you’ll see in the video:
#High-speed cold heading machines forming the screw head
#Cross slot forming and thread rolling
#Automatic washer feeding and locking
#Surface coating lines and quality testing stations
#Final packaging and warehouse dispatch