F Collar Stops
To provide a means of holding wire line equipment within the tubing string.
Is made up of four parts: *(5)1. Body (Mandrel)2. Legs3. Cap4. Trip Wires (Springs)5. * Fishneck (7” only)
The legs are compressed in and held together with trip wires latched over roll pins located at lower end of the legs, for running down the well bore. The roll pins also act as anchor pins for springs.
An 1/8 inch pin hole passes through the upper end of one of the legs and the lower body.
Ran with a collar stop running tool or jar down to shear tool. Pulled with a “JUC” or “JDC” pulling tool. Collar stops will set only in upset threaded and collared tubing joint connections. A 1/4” brass shear pin is required when pinning the collar stop to the collar stop running tool.