A Portable Wellhead Control Panel is cabinet on wheels or with lifting handles, small size and limited to control only a single well it is used to operate all safety valves that are attached to one Christmas Tree including the Downhole Safety Valve, which is installed below the surface in the Well. The Portable unit will come with flexible high pressure hoses with non-spill quick connectors to ensure that no hydraulic oil will be spilled during connection and disconnection of the hoses.
The built up of this panel can be split in several section, namely the hydraulic power unit and the control section.
The hydraulic power unit consist out of a hydraulic reservoir, a pump that can be either air/gas or electric driven. Small size accumulators to store the generated hydraulic energy for later use and to maintain pressure.
The HPU will have various pressure levels required to operate the system, the various levels can be achieved by use of pressure regulators or various pumps with different outputs, however should be limited as much as possible to keep the total weight as low as possible.
The control section is usually operated at a low pressure, which can be pneumatic or hydraulic. It consist out of various possible sequences in operation and various shutdown levels (should be kept simple and straight forward in order to keep the total weight to the minimum), but in the end will be open/close the safety valves in the field in the correct way.
WHCPs may have multiple applications, which include, but are not limited to
The WHCP internal hydraulic circuit has tubing (small bore pipe), tube fittings (twin ferrule or threaded), check valves, isolation valves, quick exhaust valves, etc. as per requirement.
Sizing of accumulators should be kept a small as possible and these should only be there to maintain pressure at a certain level for a period of time in event of small (internal) leakage due to temperature changes.
