Truss and rigging
Doughty T58120: swivel connection and movement review
Identify the Lightweight Swivel Coupler for joining two tubes before selecting accessories and configuration.
Identification and application
T58120 is Doughty’s polished Lightweight Swivel Coupler; T58121 is the black version. The data sheet specifies Ø48–51 mm tubes. It is a pair of swiveling half couplers, not the T58100 half coupler or the fixed parallel version.
For a tube connection quote, send the purpose, marking photos and an approximate sketch. We can compare a swivel, a documented fixed accessory or another arrangement, with review of forces and the receiving structure.
Prepare the proposal
- Identify both tubes, actual diameter, surface, orientation and connected parts. Sketch the load direction and intended movement; the accepted diameter alone does not establish the installation.
- Link the SKU and inspection records to the delivered piece. The manual distinguishes use and installation conditions; a fixed connection specification does not replace the swivel specification.
- If slipping, noise or a new mark appears, stop use and notify the responsible team so the area is kept clear under its procedure. Record the connected parts and what you observed. The assembly must be reviewed before reuse; do not intervene under load or try to compensate with extra tightening.
Questions and alternatives
Does swivel mean it can be a powered joint during the show?
The name describes the accessory and its relative rotation. To assess movement during the show, describe the motion, equipment and audience position, and request a competent review of the application and alternatives. The swivel function alone does not confirm that the proposed movement is acceptable.
What changes if equipment moves or is above people?
The Lightweight Swivel & Fixed Couplers manual, Revision 10, requires an M12 self-locking nut to replace the standard nut and wingnut in that condition. Ask the competent person responsible to check the applicable components and procedure. The nut change does not remove the need for secondary retention or system review where required.
Can slipping be fixed by increasing torque?
Tightening is not a capacity increase. The manual warns of deformation from excessive torque. Record tubes, accessory, orientation and the finding for competent inspection before reuse.
Can equipment and review be requested separately?
Yes. You can ask about component supply, technical review or both. With tube and marking photos and a preliminary sketch, we can review which references to assess and what information is missing. The proposal details the components, review and installation quoted for your project.
Manufacturer sources
Related references
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