Screw Pin Shackles vs. Bolt Shackles: How to Choose the Right One for Your Job
In rigging operations, shackles are indispensable tools for completing various suspension and support projects, enabling quick and temporary connection and disconnection. A key component is the shackle bolt, and different shackle bolts are suitable for different tasks. Choosing the correct pin shackle ensures efficient and safe operation. Choosing the wrong pin shackle will seriously affect the work results and create safety hazards. Therefore, it is essential to select the appropriate shackle type based on the specific application. Today, we will discuss two common pin types: threaded pin shackles and bolt shackles, and help you choose the right shackle bolt for your needs.
Table of Contents
What Is A Shackle?
A shackle is a U-shaped or jaw-shaped connector used to attach slings, chains, or wire ropes to various rigging, traction, lifting, or hoisting devices. Taking a bow shackle as an example, all shackles consist of four basic components: the bow section, body, pin, and shoulder. The bow section is the curved portion opposite the pin, used to bear the weight of the load. The boy are part of the shackle body and are used to support the pins. The pin is typically a steel bolt that connects two lugs. The shoulder is the part where the pin contacts the lug; it contacts the lug when the pin is fully tightened. Shackle pins vary and are suitable for different scenarios. Therefore, understanding the characteristics of these shackle pins is crucial for selecting the appropriate shackle.
What Is A Screw Pin Shackle?
A threaded pin shackle consists of a threaded pin that passes through one lug of the shackle and screws into the other. When properly tightened, the threads of the threaded pin are fully engaged, firmly gripping the lug of the shackle, while the shoulder of the shackle is tightly connected to the shackle body. In this way, the threaded pin shackle can securely fasten cargo, providing a strong and durable connection.
The advantage of this pin-type shackle is its ease of quick and easy connection and disassembly in rigging operations. Compared to other shackle types, threaded pin shackles offer the fastest connection and disassembly speeds, making them ideal for temporary rigging operations.
What Is A Bolt Type Shackle?
Bolted shackles, also known as safety shackles, consist of a threadless pin, a nut, and a cotter pin for secondary locking. The shackle is secured by a combination of bolts and nuts, with the cotter pin at the end providing extra safety for rigging operations. The boltless pin eliminates the need to screw the pin into the other lug. Bolt type shackles offer a wider range of specifications and can withstand higher loads than threaded pin shackles. The size of bolt type shackle is 3/16inch to 4inch, the working load limit (WLL) is 1/3 t to 150t.
Bolt type shackles provide more durable safety and are ideal for extended use. Especially when the load may shift, vibrate, or rotate on the pin, other types of pins may fail or loosen, while bolt type shackles maintain a proper connection, preventing the pin from loosening.
Read: A Comprehensive Guide To The Different Type Of Shackles
Which Shackle Is Right for Your Job?
When choosing between bolted and screw-type shackles, consider the following factors to find the shackle best suited for your lifting, rigging, and towing needs. Both types of shackles have their advantages and are suitable for different applications.
1.Safety
Safety is the primary concern in rigging operations. Shackles must remain securely fastened throughout the entire operation, without breaking or falling off. Both pin-type shackles and bolt-type shackles can handle most rigging operations within normal working load ranges. However, bolt-type shackles are safer than screw-type shackles, and the cotter pins securing the bolts provide an extra layer of safety.
Read: Why Working Load Limit is so important?
2.Durability
Durability refers to the lifespan of the shackle, whether for temporary or permanent applications. Screw-type shackles are suitable for short-term use, allowing for easy disassembly, frequent adjustments, and tightening of the screws. When in use, the threads on the pins of screw-type shackles are fully engaged. However, over time, the pins gradually loosen after each use. Bolt-type shackles, on the other hand, are specifically designed for permanent use, requiring no adjustments. Secured by cotter pins and bolts, they have a longer lifespan than screw-type shackles.
3. Application Type
Different application scenarios require different shackles. While both screw shackles and bolt shackles can be used for rigging, binding, towing, and suspension applications, one type is superior in certain scenarios. For example, in temporary applications such as binding, towing, and material handling, screw shackles offer quick release and easy disassembly. In sling, sunshade sail, and steel structure work, bolt shackles are required for permanent securing and suspending of wire ropes.
Conclusion
Choosing the appropriate pin shackle is crucial for rigging operations. Sail Rigging offers a variety of sizes and models of threaded pin shackles, including galvanized and stainless steel options. Choose screw shackles for temporary or quick operations. Choose bolt shackles for long-term, high-safety, or load-bearing applications. Always choose bolt shackles for structural lifting point operations. Regardless of the type of pin shackle chosen, always operate within the working load limits. If you have further questions about shackles, contact Sail Rigging for more information.
