Function or application of wellhead control panel

Gas wells and oil wells has a high potential hazard, either because the material ejected flammable nor the potential hazard of the gas pressure is high. Making oil well or gas well in X-mastree (well his head) are always installed valve. Its function is to shut down the well in case conditions that harm or for other interventions as well as the work test, etc.
Here I will only discuss WHCP from gas wells, as I understand. Function or application WHCP depending of each type of wellhead control panel. There is a simple, until there is a tricky. If it can be inferred is actually a function of well head control panel is to operate well, be it for shut in and POP (put on production). With the wellhead control panel we able to open or closed the DHSV via the push button contained  in panel. Also we can also open or close a master valve or wing valve with button push button as well. It was all done manually, by pressing or pulling a button push button. But to close the DHSV, Master valve, Wing Valve can be done automatically, namely through the integration with shutdown system from the well. Surely this should follow the philosophy of the shutdown system used by each company .

By looking at the picture, then it will give an overview of what functionality or usability of the wellhead control panel. The components iare visible in the picture can be grouped into:
All of these components will give feedback or as a input signal to the Wellhead control panel (WHCP). While in the well itself (flowline) there is a sensor that is used to monitor the condition of the well, either to shutdown the system, or just for readability only. Instrumentation for shutdown system e.g.:

• PALL (pressure switch low low)
• PAHH (pressure switch high high)
• The Fusible plug (for detection of fires), usually mounted above fangles, or parts that there is a possibility of leaks (the source of fire)

The instrumentation used for reading, for example:

• FR (flow recorder)
• PR (pressure recorder)
• TR (temperature recorder)

The Final element of the system shutdown:

• DHSV, Down hole Safety valve ( drived by hydraulic power)
• MV, master valve (drived by hydraulic power)
• SSV, surface safety valve (drived by pneumatic power)
• Choke valve, manually  operated
• SDV (shutdown valve) installed  in flow line of well, outside the part of the wellhead (X-mastree)

 Valves are a part of which will receive command of the signal to be opened or closed  from Wellhead control panel. So if  I can give analogical WHCP is a controller (within the science control system), SSV, MV, DHSV, SDV are the part that receives the output from the controller, while the PALL, PAHH, fusible plug is the input of the controller. But don't imagine WHCP like PLC in General. WHCP I discuss here is that it uses control pneumatic or hydraulic. Why WHCP generally use pneumatic control, because most of the well gas wells far location (remote) so hard to find sources of energy such as electricity. And generally WHCP from gas wells using gas from the well itself as a source of pneumatic power. Later will be discussed where the pneumatic power source to run the WHCP. With pneumatic power from gas, we can also have hydraulic power, i.e. by install the hydraulic pump on run by pneumatic power. Hydraulic power is used to run valve actuator  which relatively large power needs. Pneumatic-powered convert  hydraulic power can become larger. By using the pump.