A Piper International Company
ANNULAR BLOWOUT PREVENTERS
PRESSURE CONTROL PRODUCTS
TUBING & ROD STRIPPERS
TESTING & RECERTIFICATION
Torus Blowout Preventers
& Well Control Products
WELL CONTROL TECHNOLOGY BY TORUS
The Torus Annular Blowout Preventer is a unique design in well control technology. Unlike other annular units, the Torus employs no metal fingers in its packing element. This allows the BOP to close around irregular shaped or multiple objects in the well bore as well as over open hole, without damage to delicate equipment such as electric submersible pump cable or fiberglass tubing.
In addition, the Torus has no moving mechanical parts such as pistons and dynamic seals that are easily damaged by foreign material in the closing fluid. The outer packer acts as a diaphragm to transfer the hydraulic pressure to the inner packer which closes the BOP.
One big advantage of the Torus BOP is the design of the Packing Elements. The inner packing element is mostly a ‘doughnut’ of solid rubber. There are two metal rings at the top & bottom of the outside edges, to promote even closure. This is how the Torus can seal around various objects in the bore, without cutting or damaging items such as Electric Submersible Pump cables.
The packing element of the Torus, requires time to ‘relax’ to the fully open position. The amount of time required depends on several factors, such as; temperature and the duration and extent of the closure. Our warranty does not cover left closed overnight.
Under the coldest conditions, it can take up to several hours to for the unit to completely open. Under ideal conditions, it will take only a few minutes. We recommend the Torus BOP be heated in extreme cold service. This will enhance the sealing ability at a given closure pressure and speed opening of the unit, improving productivity and product life. Our warranty does not cover damage from cryogenic operation (while frozen solid).
After each cycle, the blowout preventer bore should be inspected to determine the packer position. When completely open, the packer recedes into the steel body of the blowout preventer and will not contact objects moving through the bore. Failure to allow the BOP to completely open can result in damage to the inner packer.
GREAT POTENTIAL FOR ‘ENHANCED OIL RECOVERY’
The Torus Annular Blowout Preventer is well suited for a variety of drilling and well servicing applications. One of its greatest potential uses is in enhanced oil recovery projects (EOR).
The Torus is ideal for closing around tubing and the wire conduit of an electric submersible pump associated with EOR projects. While other blowout preventers employ packers with metal fingers (see photo below) covered by a small amount of elastomer material, the Torus packer is a donut shaped mass of elastomer reinforced by two steel rings. The Torus closes via direct hydraulic force, causing the packing element to form tightly around tubing and conduit. If a spiral wound steel jacket covering the wire is employed, a minimal leak can be expected. In neither case will conductivity of the wire will not be disturbed.
Other BOPs have “Metal Fingers”
The Torus does not employ piston operation of the packer; instead it uses direct hydraulic force. This allows the packer engaging the object in the bore to be carefully regulated, which keeps it from closing with excessive force. Very often fiberglass tubing will be used in EOR projects. To prevent collapse, the operator is advised to carefully monitor the closing force of the blowout preventer.
The Torus employs a very simple pressure close, vent open method of operation. To close, hydraulic pressure is applied via an outside source, i.e. an accumulator or rig hydraulics. To open, the same line permits the hydraulic fluid to vent back to the hydraulic reservoir. A simple regulator installed in the line will give the amount of pressure necessary for the packer to engage the object in the hole to effect a “shut-off”, but not more than what is required to overcome the downhole pressure.
