The accessories of MSC/HSC Stage Cementer include a first-stage plug, free-fall opening plug, closing plug, shut-off baffle and pumping-down opening plug. Being made of rubber or aluminum, these parts are drillable.

Free-fall Opening Plug

1. The shut-off baffle is installed in the casing collar, one joint above the float collar.

First-Stage Plug

The first-stage plug is used to isolate the first-stage cement and drilling fluid. On the end of displacement，the first-stage plug lands and effects a seal against the shut-off baffle.

3. Featuring streamline shape and filled with lead, the free-fall opening plug can quickly free-fall to the lower sliding sleeve. When pressure is applied to the casing, it can open the circulation ports.

Shut-Off Baffle

4. The closing plug is used to isolate the second-stage cement and drilling fluid. When running to the upper sliding sleeve, it effect a seal in the stage cementer. Pressure is applied to the casing and the circulation ports are closed.

5. The pump-down opening plug is used for continuous cementing operation and in deviated wells. It can open the circulation ports directly and quickly, whereas the free-fall opening plug needs longer time waiting for falling.

Pumping-Down Opening Plug

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