Wellsite Valve Manifolds Simplified —By Joseph Zawacki

: Connecting multiple production wells or flowlines to a test separator normally requires multiple valves, each of which has to be opened by hand to connect each well in turn. In addition to valves and shutoff devices, such a system requires considerable piping. A multiport flow selector (MPFS)—with automatically actuated control—is safer, less expensive, lighter weight and more compact than conventional systems. 

The article describes how a MPFS works and details its advantages over conventional installations.

   

Joseph Zawacki, Vice President of the Hydraulics Strategic Business Unit at Emerson, explains how a multiport flow selector can save time and money as compared to conventional well site valve manifolds connected to test separators. His article, Wellsite Valve Manifolds Simplified in the April 2018 issue of Oil & Gas Engineering magazine, addresses problems common at oil and gas production wells:

 Testing constituent flows is a crucial part of an oil production process. Oil, water, brine, condensate, gas and other fluids must be monitored and measured regularly. Historically, wells were connected to a complex piping network with two manifolds. One manifold connects all wells to production, and a second manifold connects the well selected for testing to a shared multi-phase flowmeter or separator.

 While this conventional approach uses common valves, actuators and piping components, it is more expensive and electrically complex than a multiport system. For example, a conventional seven-well, two-way well test manifold requires 21 valves. And it takes a lot of time and labor to run a test, Joe says:

 If a well needs to be tested, a technician manually closes the production valve, then manually opens the valve to the test separator. The well is then directed to the test facility, while all other wells continue feeding the production line. Depending on the test equipment, the flow set up and size of the separator, a test can take several hours. 

All of this obviously takes quite a lot of field trips and time for the operators, and this is why well companies don’t get very frequent test data for the wells with conventional manifold systems. Typical onshore oil & gas production sites have wells scattered over a large area, so it is difficult to manually open and close the manifold on/off valves. For these reasons, many well operators would like to automate test flow diversion. The solution is to use a Fisher multiport flow selector (MPFS), as Joe explains: 

An MPFS that’s controlled remotely, provides savings by reducing the number of valves and the labor to operate the valves, as well as potentially improving safety. For example, a seven-well system with a MPFS requires only seven valves as compared to 21 with a conventional system, eliminating the cost of 14 valves and associated piping. It also eliminates the need for operators to open and close valves manually, and it reduces valve maintenance. 

A Fisher MFPS greatly simplifies piping, especially on cramped offshore platforms. It also eliminates the need for a technician to manually open and close valves in a dangerous environment. An MPFS provides an additional advantage in sour oil and gas fields, which often require special materials at points of contact. For example, when high nickel-chromium internal cladding is required, the simplified piping and fewer valves results in much lower cladding cost. Joe summarizes: 

Using a MPFS at oil and gas production well sites improves testing and reservoir management, reduces the costs of valves and piping, and cuts labor costs. Automating typically manual operations can improve safety. An MPFS provides cost-effective diversion of fluids from individual wells for testing, without disrupting the production from other wells.