Superbolt Expansion Coupling Bolts

Superbolt sj style mechanical tensioners used when limited headroom and thread engagement are required.
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This innovative Superbolt product replaces large fitted or interference fit bolts.


  • Easy: Loose fit sleeves (up to .010″ – .020″ in the through-hole) are easily inserted even in holes misaligned due to rotation. Only hand tools are required for installation and removal.
  • Fast: Tightening requires only minutes per assembly.
  • Safe: Eliminates the need for special high powered tools and bolt deep freezing. Torque required is usually under 100 ft-lbs. Entire assembly requires only hand tools.
  • Economical: Saves money over alternative solutions in time and tooling. No need to ream/hone the bolts as normal machine precision is sufficient.
  • Reusable: The split sleeve springs back to original size, use after use. Compared to the close tolerance solid sleeves found in other systems, the loose fit split sleeve is much less likely to hang up during removal.
  • Generates axial and radial force simultaneously. Easier to “pull together” coupling halves.
  • No reaming/honing required: Only line boring of holes is necessary.
  • No coupling face machining is required (where the nuts seat). The multi-jackbolt design compensates for small variations in perpendicularity of the spotface to the hole centerline.
  • Eliminate finish machine of sleeves on site: Generous sleeve expansion permits finish machining in advance.


  • 1. Slide split tapered sleeve (2) onto the tapered stud (1) and place togeather in the bore.
  • 2. On side (A), place spacer (3) in the bore to center split sleeve between the split line.
  • 3. On side (A), slide washer over the tapered stud (1) and screw on the Superbolt tensioner (4) by hand.
  • 4. Tighten jackbolts stepwise according to tightening procedure.
  • 5. On side B, slide the hardened washer over the tapered stud (1) and screw on the Superbolt tensioner (5) by hand.
  • 6. Tighten jackbolts stepwise according to tightening procedure.
  • 7. Verify Superbolt tensioner torque on side A.
  • Removal

  • 1. According to removal procedures, loosen the jackbolts on side A stepwise and unscrew the Superbolt tensioner (4) by hand.
  • 2. Tighten several Superbolt tensioner (5) jackbolts on side B further, in order to release the tapered stud (1) off the tapered sleeve (2).
  • 3. Unscrew the Superbolt tensioner (5) by hand.
  • 4. Remove tapered stud (1), tapered sleeve (2, and spacer (3) from the bore..