This paper describes the construction method of operation and fieldperformance of the multiple completion choke assembly developed by the Sun Oil Company.
This down-hole commingling tool has been in operation since March, 1960. Ithas been used in approximately 75 wells located in Louisiana, Texas, Mississippi, Oklahoma, Mexico, Kuwait and India.
Sun Oil Company's Gulf Coast Division, through the use of this tool duringthe past four years, has saved approximately $289,000 in tubular goods, andproduced approximately $282,750 worth of hydrocarbons not otherwiserecoverable.
The paper reports the results of Sun Oil Company's installations anddiscusses the various applications and limitations of the tool.
The method of allocating production to each zone is explained and theadvantages and disadvantages in the simultaneous production of two separatereservoirs through a single tubing string are enumerated.
Construction and Operation
Figure 1 shows a well equipped to receive a multiple completion chokeassembly. A retainer-type packer separates the two producing zones. The upperpacker is optional. A side-door choke landing nipple hookup is located in thetubing string above the lower packer. The multiple completion choke assemblywill be locked in this landing nipple. Normally located a joint or two abovethe upper zone, the position of the landing nipple hookup can be varied to suitwell conditions. For example, where the two zones are widely separated, itmight be placed just above the lower packer to facilitate bottom-hole pressuretests of the lower zone.
The tool consists of two separate assemblies, as shown in Figure 2.The outer assembly, which is run on a wire line and locked in the landingnipple, contains the check valves and packing seals which prevent flow from onezone to the other.
The orifice-head assembly, which carries the tungsten carbide choke beans, is run separately and is seated and locked in the outer assembly. The method ofrunning each section is illustrated in Figure 3.