The WSB Annular BOP consists of just five major parts and only two moving parts, which are the piston and the packing unit. This means few areas are subject to wear. The BOP is safer and more efficient, requiring less maintenance and less downtime.
The WSB Annular Blowout Preventer will seal the through-hole with a reinforced elastomer packing element. The packing element is hydraulically energized. Once the seal has been achieved, through-hole pressure acts upon the piston to assist in maintaining the seal.
The packing element will seal around various shapes and sizes of pipe. In an emergency, the sealing element will maintain a tight seal for complete closure of the through-hole.
Rotating drill pipe can be stripped through the packing element while maintaining a seal. The BOP has internal coatings which reduce friction and wear. Reduction of friction and wear increases the useful life of the seals. The internal coatings also protect the metal parts from corrosion.
The spherical element of the WSB Annular BOP is manufactured with high quality rubber and is reinforced with forged steel segments. The forged steel segments control the extrusion and flow of the rubber when sealing off well pressures. Because the rubber is confined and kept under compressions, it is resistant to cuts, tears and abrasions.
The packing element is subject to wear during closure and stripping. Wear from closure occurs on the outside of the element and wear from stripping occurs on the inside of the element. Closure wear has minimal effect on stripping life.
Specification and Features
• Rugged, reliable sealing element provides positive seal after hundreds of tests to full working pressure.
• Strong, simple construction – only five major parts.
• Compact body saves space. Height is 15 to 20% less than height of some other annular BOPs.
• Simple hydraulic system. Only two hydraulic connections are needed.
• Wear rings on moving parts prevent metal-to metal contact. This feature prolongs preventer life.
• Suitable for H2S service. Standard models are sutiable for internal H2S service, and simple bolt and lifting shackle changes convert them for external H2S service.
• Special lightweight models can be carried by helicopter.
• Servicing is easy. Element can be changed without getting mud or grit into the hydraulic system.
• Steel segments reinforce sealing element but do not protrude into well bore when element is open.
• Element design provides long stripping life.
WOM’s Type WSB BOP was designed especially for surface installations and is also used on offshore platforms.