Open body turnbuckles are adjustable rigging connectors featuring an open, hollow sleeve design. They are characterised by flexible tensioning and stepless adjustment of rope tension, and are commonly used as tensioning and fastening components in engineering applications.
Structure and Principle
Structural components: a hollow, open-ended adjustment sleeve; tie rods at both ends featuring left-hand and right-hand threads respectively; and tie rod ends available in two types: ring-shaped (O) and hook-shaped (C). The hollow design allows for visual inspection of the thread engagement, making assembly, disassembly and tightening more convenient.
Principle of Operation: Rotating the central sleeve causes the tie rods at both ends to retract or extend synchronously, continuously adjusting the overall length to allow for fine-tuning of the tension in wire ropes or chains.
Main Categories (by End Tip Style)
OO Type (Double Ring): Circular rings at both ends, suitable for long-term fixation and scenarios requiring infrequent disassembly, such as the pre-embedded fixing of construction tie rods;
CC Type (Double Hook): Hooks at both ends, allowing for convenient assembly and disassembly; suitable for temporary lashing and frequent tightening, such as in greenhouses and freight lashing;
CO Type (One Ring, One Hook): Combines fixation with quick-release functionality, suitable for working conditions where the assembly and disassembly requirements differ at each end.

• Stepless micro-adjustment of length to compensate for installation errors and precisely control pre-tension;
• Open-body design with visible threads, making it easy to detect loosening and simple to prevent it;
• The forged version offers high strength, suitable for load-bearing applications such as lifting and heavy-duty lashing;
• Easy to install, with tension adjustment possible without complex tools.

Tensioning of steel structures in construction; tightening of guy wires for power and telecommunications; securing ship rigging; temporary bridging supports; securing freight cargo; tensioning of polytunnels and shade nets; and stage rigging and cable adjustment.

Prioritise the forged version for heavy loads and high-frequency stress; for standard static lashing, the standard carbon steel version is suitable; take care to prevent the hook-type end from coming loose, and it is recommended to use anti-loosening locking devices for critical structures.