Please read this shackle instruction manual carefully before installation and use.
This document provides essential information for safe operation, inspection, and maintenance of shackles used in lifting and rigging applications.
Contents
- Product Characteristics
- Main Use and Scope of Application
- Structural Sketch
- Installation and Debugging
- Use and Operation
- Connection and Fitting Requirements
- Maintenance
- Discard Standard
1. Product Characteristics
The shackle is a forged alloy steel component designed for connecting lifting slings, hooks, or loads in hoisting and rigging systems.
Each unit manufactured under strict process control, including precision forging, heat treatment, and surface protection to ensure strength, reliability, and long service life.
- The material has excellent tensile and fatigue strength, maintaining stability under dynamic load conditions.
- All products undergo proof testing at 2 times the rated working load limit (WLL) and designed with a minimum safety factor of 4:1.
- Shackles are available with screw pins, round pins, and bolt-type configurations, suitable for different load and assembly conditions.
- Surfaces treated with galvanization or special coatings to resist corrosion and oxidation in outdoor environments.
- Each shackle permanently marked with size, load rating, and manufacturer’s identification for traceability and inspection.
2. Main Use and Scope of Application
Shackles serve as critical connecting components between lifting slings, hooks, or other load-bearing devices in hoisting systems.
They are suitable for construction, marine, mining, port handling, offshore, and heavy machinery industries.
Typical applications include:
- Connecting wire rope, chain, or synthetic sling to lifting hooks or spreader beams.
- Serving as removable joints for lifting assemblies where frequent connection and disassembly required.
- Acting as end fittings on slings when direct attachment to the load is necessary.
- Substituting for lifting rings to connect to the beam ear plates or crane pulley blocks.
Shackel Selection guidelines:
- D-type shackles are ideal for single-leg lifting or straight-line tension.
- B-type shackles (bow-type) accommodate multi-leg slings or angular loads.
- BW / DW shackles used where the sling does not rotate the pin.
- BX / DX shackle recommended when rotation may occur or for long-term fixed installation.
3. Structural Sketch
The following diagrams illustrate typical structures of shackles:
- DW Type – Long-term fixed installation, straight tension.
- DX Type – Long-term fixed installation, adaptable to multiple lifting angles.
- BW Type – Suitable for single lifting ring or hook connection.
- BX Type – Suitable for multi-leg sling assemblies and dynamic rotation.
Each model consists of a bow (body) and a pin (bolt or screw).
The contact surfaces between the bow and pin designed for even load distribution and smooth rotational motion.
4. Installation and Debugging
Before installation, verify that the rated load, size, and pin type of the shackle match the intended lifting device.
Inspect the threads, pin holes, and body curvature for wear, cracks, or deformation.
- Hang the shackle directly into the hook’s centerline to ensure even stress distribution.
- Never attach the shackle to the tip of a hook or across sharp edges.
- Ensure that the pin threads are fully engaged and securely tightened by hand (do not hammer).
- When connecting with a single-leg sling, the sling eye should rest freely within the shackle bow.
- Avoid side loading; the pull direction must align with the shackle’s body centerline.
After installation, rotate the pin to ensure smooth movement.
If the shackle cannot rotate freely, recheck alignment and pin fit before use.
5.Use and Operation
The rated load and application scope of shackles are determined under standard lifting conditions.
Overload, side load, shock load, or improper connection are strictly prohibited.
Operating Guidelines:
- Lift loads slowly and steadily to prevent dynamic impact.
- Do not allow the load to strike or drag the shackle during lifting.
- Keep personnel clear of the suspended load at all times.
- Avoid rotating the shackle under tension.
- Perform a trial lift to verify balance and stability before the full lift.
Temperature Influence:
The allowable working load changes under extreme temperature conditions.
| Temperature (°C) | -20~0 | 0~200 | 200~300 | 300~350 | 350~400 | 400~475 |
|---|---|---|---|---|---|---|
| S(6) Rated Load (%) | 100 | 100 | 90 | 75 | 75 | Not allowed |
| T(8) Rated Load (%) | Not allowed | 100 | 90 | 75 | 75 | Not allowed |
Excessive temperature variation may alter the mechanical properties of steel.
6.Connection and Fitting Requirements
- The thickness of the ear plate or connected component shall not be less than the pin diameter.
- The bearing surface must be smooth and free from burrs to prevent stress concentration.
- Avoid using shackles where the load direction deviates more than 10° from the vertical axis.
- Do not insert multiple fittings into a single shackle unless designed for that purpose.
- For multi-leg lifting assemblies, use bow-type shackles to maintain correct sling alignment.
Correct force alignment is essential.
If the shackle bears load at an angle or on the pin threads, the rated load capacity will significantly decrease.
Figures 6–8 show typical examples of correct and incorrect usage in lifting applications.
7.Maintenance
Routine inspection and maintenance are vital to ensure safety and reliability.
- After use, clean the shackle to remove dirt, oil, and corrosive residues.
- Apply a thin film of anti-corrosion grease to threads and pin contact surfaces.
- Never drop shackles from height — impact can cause hidden cracks or structural damage.
- Store shackles in a dry, ventilated, and shaded area, avoiding contact with chemicals, acids, or moisture.
- Shackles exposed to seawater or outdoor environments should be inspected more frequently for corrosion.
- Maintain inspection records including date, location, load conditions, and observed wear.
A regular inspection interval of every 3 to 6 months is recommended for frequently used shackles.
For critical lifting operations, perform a visual check before each use.
8.Discard Standard
Shackles must be immediately replaced or discarded when any of the following conditions are observed:
- The body is twisted or bent by more than 10°.
- Wear or corrosion exceeds 10% of the nominal diameter.
- Cracks or fractures detected by visual inspection or non-destructive testing.
- Permanent deformation of bow or pin under load.
- Thread damage preventing full engagement of the pin.
- Loose or missing safety nuts or cotter pins (for bolt-type shackles).
Do not attempt to repair a defective shackle by welding, heating, or straightening.
Always use certified replacements of the same model and rated capacity.
