snatch block
Noun: A snatch block is a specific type of pulley block designed with a side plate that can be opened or "snapped" shut. This opening allows the user to easily insert the middle section (the bight) of a rope or cable into the sheave (the grooved wheel) without having to thread the rope through from one end. It is primarily used in rigging, lifting, and hauling operations to change the direction of a rope's pull or to create a mechanical advantage.
The term "snatch block" is used to describe this tool in contexts involving ropes, cables, winching, sailing, construction, and recovery operations (like vehicle recovery). It is a technical term from rigging and maritime vocabulary.
- Noun:
- We used a snatch block to redirect the winch cable and pull the vehicle straight out of the ditch.
- The sailor quickly attached the snatch block to the stanchion to change the direction of the halyard.
- For a safer and more efficient pull, always secure the snatch block to a solid anchor point.
- "Rigging a snatch block": The process of correctly attaching and using a snatch block in a system. This involves ensuring the side latch is securely closed and the block is properly anchored.
- Properly rigging a snatch block is essential for safety during heavy lifts.
- Pulley block (n): A more general term for a block containing one or more sheaves. A snatch block is a type of pulley block.
- Sheave (n): The grooved wheel inside a block over which the rope runs.
- Block (n): In rigging, a general term for a casing containing one or more sheaves.
- Side-opening block: A descriptive synonym that emphasizes its key feature.
- Snatch pulley: A less common variant of the term.
The defining characteristic of a "snatch block" is its openable side, which distinguishes it from a standard "block" or "pulley block" that requires the rope end to be threaded through. Its function is not just to hold a pulley, but to provide a quick and convenient method for engaging a rope already under tension or with fixed ends.
- a pulley-block that can be opened to receive the bight of a rope