Definition
Safety Clamp — A safety clamp is a hinged, bolt-tightened collar of interlocking segments installed around a smooth-bodied drill collar or tubular as a backup that rests on the slips or rotary table to prevent the string from slipping and falling into the hole.
Also known as: drill collar safety clamp, safety clamp, C-type clamp
What a safety clamp does
A safety clamp is a mechanical failsafe used when handling drill collars and other smooth, untapered tubulars that offer no shoulder for the slips to grip reliably. The clamp is built from hinged segments that wrap the pipe and are drawn tight with through-bolts. Once set above the slips, it provides a positive shoulder so that, if the slips lose grip, the clamp lands on the rotary table or master bushing and arrests the string.
Because drill collars are heavy and have a slick outside diameter, running them without a safety clamp risks a dropped string. The clamp is sized to the collar OD, and enough segments must be used to develop adequate holding capacity for the weight being handled.
Correct installation
- Match the clamp to the tubular OD so the segments seat evenly.
- Tighten all bolts to the specified torque for full gripping force.
- Set the clamp above the slips, never as the primary support, so it acts purely as a backup.
Why it matters for rentals
A worn or under-sized safety clamp defeats its purpose. Rental clamps should have undamaged gripping faces, sound hinge pins and correctly rated bolts. Explore our handling tools or contact us with your drill collar sizes for a matched set.