Position the tensioner
The main body is threaded onto the bolt, stud or shaft against the hardened washer.
High preload with hand tools
Superbolt Multi-Jackbolt Tensioners
A mechanical tensioning system that replaces large conventional nuts or bolt heads with multiple jackbolts around a central thread.
Nord-Lock Group technologyProduct overview
Built for secure, serviceable joints.
Superbolt multi-jackbolt tensioners divide the tightening work across several smaller jackbolts. Each jackbolt can be torqued with ordinary hand tools, transferring preload evenly into the main bolt or stud.
- Tensions large bolts with compact hand tools
- Useful where space or overhead clearance is limited
- Applies preload gradually and evenly
- Direct replacement options for many conventional nuts and bolts
- Reduces dependence on large torque tools
How it works
Distribute one large load
The tensioner threads onto the main bolt or stud and bears against a hardened washer before the surrounding jackbolts are tightened.
Snug the jackbolts
The smaller jackbolts are brought into contact in the specified sequence.
Apply preload
Successive passes transfer force through the body and stretch the main bolt in tension.
Confirm the sequence
Final jackbolt torque and the tightening pattern are checked against the application procedure.
Typical applications
Where this solution fits.
01Large flanges and pressure equipment
02Mining and heavy processing machinery
03Power generation and turbines
04Marine and offshore equipment
05Space-restricted large-bolt connections
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