The purpose of the RIGGER ENGINEERING shear pin adapter is to suspend the liner wiper plug in the hole below the cup mandrel or slick joint stinger during the cement operation.
The wiper plug is installed at the bottom of the adapter by removing the shear pin cap and sliding the aluminum landing collar into the bore. Brass pins are inserted through holes and into a groove in the landing collar to hold the plug assembly in place. The shear pin cap is then screwed back onto the mandrel to hold the pins in place. After cementing, the drill pipe dart is launched from the cement head. It travels down the drill pipe and lands in the wiper plug landing collar where it locks in place via a snap ring. Pressure build-up shears out the brass pins and the plugs move down the liner as a single unit.
A seperate option uses brass set screws in place of the brass pins. This eliminates the need for the cap which holds the pins in place. This option is especially useful where tight restrictions do not allow for the additional size of the cap.