Emergency Shut Down Valve
This compact electric over hydraulic accumulator is easily loaded by one man into a pick up for transportation to location. The Emergency Shut Down Valve (ESD) consists of a Damcos BRC 250 double acting balanced rotary actuator which operates open or closed on .05 litres or 50 cc of hydraulic fluid.
The actuator consistently opens the valve a true 90 degrees, allowing for drifting or running of full bore tools through the valve. The hoses are equipped with locking hydraulic couplers to avoid accidental disconnects. The hydraulic actuator will allow opening the valve under pressure as high as 14 mpa if required.
The hoses are coupled at 9.5 m to allow quick disconnects for connections and to avoid passing bulky hoses around tubing when making joint connections.
The actuator is equipped with a highly visible indicator to alert the operator of valve status at all times. This indicator also allows functioning the valve without removal of ESD in the event of a hydraulic failure. The open center control valve allows for quick reconnect of couplers without pressure on hoses.
The magnet base allows for mounting of the controls on any metal surface for driller or operator convenience.
The 1.13 litre accumulator allows for six complete functions of the valve without electric power. There is also a heavy duty quick release valve clamp for fast changeovers from valve to valve.
- Pressure switch set @ 1500 psi working pressure on accumulator
- 1.13 litre accumulator
- 1 hp intrinsically safe electric motor
- Locking quick couplers
- Magnetic control base
- Open centre control valve
- 3000 psi hydraulic hoses
- Quick release valve clamp.
Downhole Shut In Valve (DHSV) WR Retrieval Assembly
Advantages of the DHSV WR Retrieval Assembly versus Tubing Plugs:
- Allows the tubing to be flowed at any time by rotation of the tubing to function the DHSV into the open position
- Eliminates tubing plugs, wire line, and TIW rental cost
- Time effective compared to setting and pulling tubing plugs
- Design ensures that there will never be a sudden failure that allows an uncontrolled release of gas up the tubing string
- Designed to function in a sand environment
The cost comparison on a WR Assembly with a DHSV shows up to a 50% savings compared to tubing plugs. These savings are due to the elimination of the Slickline Unit, and additional rig and snubbing cost to pull and set the plug. In addition, fewer TIW valves are required, saving the customer valve rental and re-certification costs.
- Components are assembled as pictured right with the DHSV in the closed position.
- The tool string is then picked up and staged into the well bore.
- Tubing is run as necessary to WR depth or sand/fill.
- If it is required to circulate onto the WR, the circulating package consisting of a 5,000 psi chicksan and a kelly hose would be rigged in at surface.
- The DHSV anchor is then set and the tubing rotated to open the DHSV. Equalizing above the DHSV may be required depending on the differential pressure across it. A high differential pressure may cause difficulty in opening or closing the DHSV.
- Proceed with cleanout to WR.
- The DHSV can be opened and closed as many times as necessary to make the connections required to clean out to the WR depth.
- Once the well is cleaned out to the WR, it would be latched, equalized, and released.
- With the WR released, the DHSV would be closed, tubing bled off, and circulating equipment rigged out.
- The tool string with the WR is now ready to be pulled to surface.
NOTE: With the tubing plugs, there is always the possibility of a miss-run due to the plug not holding. This would lead to additional rig and snubbing costs. If sand was encountered unexpectedly, there may be standby time due to the availability of a Slickline Unit.
TYPE ‘C’ DRAG BLOCK ASSEMBLY/COLLAR LOCATOR:
The Type ‘C’ Drag Assembly Block/Collar Locator may be assembled either as a drag block assembly to provide friction between the tubing string and the casing wall, or as a mechanical Collar Locator to correlate the tubing depth to a well log.
Used as a Drag Block Assembly, the Type ‘C’ provides a simple reliable method of providing drag to facilitate the operation of rotational tools such as the Down Hole Shut In Valve, which is commonly used in selective injection operations. The drag pads are energized with acid resistant leaf springs to ensure reliable operation.
The Type ‘C’ may be converted to a Collar Locator simply by replacing the drag pads with locator keys. The design of the locator keys allows them to expand in the recess of an API casing collar as it passes through the collar. This results in a momentary increase in tubing force as the key is forced to collapse in order to move out of the collar recess. The keys are designed to give the most positive indication when the Collar Locator is moved upward through the collar. This action will be felt in the tubing string at surface. The Type ‘C’ Collar Locator is commonly run with service tools that require accurate positioning in the well.
The Collar Locator may be used either as a fixed locator which cannot turn on the mandrel and provides drag, or as a freely rotating locator that is free to rotate on the mandrel. To convert the Collar Locator to a freely rotating version, the top coupling on the Locator is replaced with a standard tubing coupler.