• secure_bolting_systems

    High load. Tight space.
    Critical bolting.

Duo and Mono tensioners

Duo and Mono series multi-stage tensioners are versatile and reliable hydraulic bolt tensioners suitable for high load and tight space applications. Duo tools feature multiple hydraulic stages to give a small tool diameter to fit into tight radial spaces. Mono tools feature low height profile to use when there are overhead obstructions.

Optimised for use on wind turbines they have been designed for long-life, low-maintenance use and are suitable for use on single bolts, or grouped together for multiple tightening of bolted joints. Duo and Mono tensioners are extensively used for slewing rings, powergen applications, structural and all critical bolting.

Duo and Mono tensioners are designed for speed.
  • Fast spring piston retract, geared nut run-down and spring located sockets, improve process time on each tensioning operation.
  • High cycle life, over-stroke protection and the latest seal technology ensure low maintenance operation to keep projects on schedule.
  • These tools generate high loads. They are designed to give an applied load equal to 95% loading on 10.9 type bolting.
  • Tools are available from stock for quick delivery.

All Duo tools are ARMOURMAX protected


Speed and safety improvement
For the Duo and Mono range of tensioners, we offer a quick fit TWIST to lock safety handle. This allows easy movement of tools from bolt to bolt for optimised speed of tensioner operation. It also adds a layer of protection for the operator by shielding the hose tool connection during pressure operations to the tensioner. See data sheet for more details

  • Mon_Duo_Tensioners
  • Duo_Multistage
  • mono_tensioner

  • special_tensioners

    Geardrive nut rundown

  • special_tensioners

    Cycle counter

  • special_tensioners

    Swivel connections


Unit 15 Morgans Business Park
Betty’s Lane
Norton Canes
WS11 9UU

Tel: +44 (0)1543 448800

Privacy policy

TensionPro is a trading name of
Secure Bolting Systems Limited

© 2023 Secure Bolting Systems Limited

Site design Wray Communications