T750 Sub-Surface Release (SSR) cementing plug system is a dual plug, dart released wiper plug system that provides operators with a method of carrying out cementing operations from surface with plugs installed at the sea floor.
The T750 cementing plug set is installed into the top joint of a casing string and lowered by drillpipe until the correct depth is reached. The well can now be circulated before cementing operations.
The bottom plug is released ahead of the cement by a wiper dart pumped down the drillstring.
After all the cement has been pumped, the top wiper dart is launched from the surface to wipe the drill pipe ID and release the top plug. The drill pipe dart lands in the top plug and shears it away from the hanger and it is pumped down the casing while wiping the casing until it lands on top of the bottom plug, sealing off the casing string.