Bolt Tensioners

Submarine Bolt Tensioning System

Engineered for high-performance subsea operations, our patented Quick Reaction Nut features a lightweight, hinged design—making it the most diver-friendly solution in the market. Constructed entirely from marine-grade stainless steel, it delivers superior corrosion resistance, extended operational reliability, and reduced diver fatigue in even the harshest subsea environments.

Subsea Tensioner Tool Plates

Optimized for subsea flange joints, Tri-Star’s custom-engineered tensioner fixture plates significantly reduce setup time and improve operational safety. Designed for bolt sizes from 3.0″ to 4.0″, these intelligent systems eliminate the need to lock in tensioners manually—streamlining complex underwater bolting procedures. Mounted on a skid for seabed deployment, the tool plate can be lifted and positioned using air bags, aligning easily with flanges to enable concurrent 50% or 100% bolt tensioning. 

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