A ram-type BOP is similar in operation to a gate valve, but uses a pair of opposing steel plungers, rams.
A ram-type BOP is similar in operation to a gate valve, but uses a pair of opposing steel plungers, rams. The rams extend toward the center of the wellbore to restrict flow or retract open in order to permit flow. The inner and top faces of the rams are fitted with packers (elastomeric seals) that press against each other, against the wellbore, and around tubing running through the wellbore. Outlets at the sides of the BOP housing (body) are used for connection to choke and kill lines or valves.
Ram BOPs for use in deepwater applications universally employ hydraulic actuation. Threaded shafts are often still incorporated into hydraulic ram BOPs as lock rods that hold the ram in position after hydraulic actuation. By using a mechanical ram locking mechanism, constant hydraulic pressure need not be maintained. Lock rods may be coupled to ram shafts or not, depending on manufacturer. Other types of ram locks, such as wedge locks, are also used.
Shaffer, Cameron, Hydril, & Other Quality Brands
|Bore Sizes||Pressure Rating||Cavity|
|4-1/16"||10,000 & 15,000 psi||Singles & Doubles|
|7-1/16"||5,000, 10,000 & 15,000 psi||Singles & Doubles|
|11"||3,000, 5,000, 10,000 & 15,000 psi||Singles & Doubles|
|13-5/8"||5,000, 10,000 & 15,000 psi||Singles & Doubles|
|20-3/4"||3,000 psi||Singles & Doubles|
|21-1/4"||5,000 & 10,000 psi||Singles & Doubles|