Qingdao Haosail Machinery Co., Ltd.

1. Raw Material Inspection

Quality control starts before production begins.

We inspect incoming raw materials according to the required material specifications and product requirements. Material condition, dimensions, and traceability are checked before the material enters the production process.

Proper material control provides a reliable foundation for the mechanical performance of the finished shackle.

2. Precision Forging

Forging is one of the key stages in shackle manufacturing.

During the forging process, we control the forming conditions and dimensions to ensure that the shackle body has a consistent structure and shape. Proper forging helps provide the strength and durability required for lifting applications.

After forging, the products are checked for visible defects and dimensional consistency before moving to the next process.

3. Heat Treatment

Heat treatment plays an important role in achieving the required mechanical properties.

The forged shackles are processed according to the specified heat treatment requirements. Key parameters are controlled during the process, helping achieve the required balance of strength and toughness.

This stage is particularly important for lifting hardware because the finished product must withstand working loads safely.

4. Machining and Pin Processing

After heat treatment, the shackle bodies and pins are machined to the required dimensions.

We check critical dimensions such as pin diameter, hole size, body dimensions, and thread accuracy. Proper machining ensures that the pin fits correctly with the shackle body and that the finished product meets the required specifications.

5. Surface Treatment and Appearance Inspection

Depending on the product requirement, shackles can receive different surface treatments for corrosion protection and appearance.

After surface treatment, we inspect the surface for defects such as uneven coating, damage, or other visible problems. Markings and product identification are also checked to ensure that the finished shackles can be correctly identified.

6. Load Testing and Quality Verification

For lifting hardware, appearance alone cannot demonstrate product performance.

According to the product requirements, appropriate testing and inspection are carried out to verify the performance of the shackles. Key requirements such as Working Load Limit (WLL), dimensions, markings, and test results are checked against the applicable specifications.

Testing and inspection records also provide important quality evidence for customers.

7. Final Inspection Before Packing

Before shipment, every production batch goes through a final inspection.

Our QC team checks the finished shackles for:

• Dimensions and tolerances

• Pin fit and thread condition

• Surface quality

• Product markings

• Quantity

• Packaging condition

• Required inspection or test documentation

Only after the final inspection is completed are the products prepared for packing and shipment.

Quality Is Controlled Throughout the Process

For lifting hardware, quality should not be something checked only at the end of production. It needs to be controlled at every important stage.

From raw material → forging → heat treatment → machining → surface treatment → testing → final inspection, each step contributes to the quality and reliability of the finished shackle.

As a manufacturer of shackles and other rigging hardware in China, we focus on maintaining consistent production and inspection standards throughout the manufacturing process, helping our customers receive reliable products for their lifting and rigging applications.