220 likes | 346 Views
2001 ASME/API Gas-Lift Workshop. Routine Validation Testing of Every Gas-Lift Valve Informal Presentation by Naiza Abdullah, Brunei Shell Petroleum Ken Decker, Decker Technology Cleon Dunham, Oilfield Automation Consulting. Routine Validation Testing of Every Gas-Lift Valve. Outline
E N D
2001 ASME/API Gas-Lift Workshop Routine Validation Testing of Every Gas-Lift Valve Informal Presentation by Naiza Abdullah, Brunei Shell Petroleum Ken Decker, Decker Technology Cleon Dunham, Oilfield Automation Consulting 2001 ASME/API Gas-Lift Workshop
Routine Validation Testingof Every Gas-Lift Valve • Outline • Brief history • Business justification for routine testing • How the tester works • Intended operational use • Field experience • Outstanding issues 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingA Brief History • History • Only the Ptro test is performed routinely • In 1995, API RP 11V2 provided standards for testing and modeling gas-lift valves • In 1996, the Valve Performance Clearinghouse, an industry JIP, was formed to implement 11V2 • Typically, the VPC tests one valve of each type • Purpose of Gas-Lift Valve, Automatic Validation Tester (GLV-AVT) is to test every gas-lift valve • Before it is run • After it is pulled 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingBusiness Justification • Rationale for testing each valve • Not all valves of a specific type are manufactured to the original specifications • Some companies are not API certified • Some valves may be damaged in handling • Many operating companies re-run used valves • Operating conditions in wells vary • Operators need a high degree of assurance that valves will perform as intended 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingBusiness Justification • Justification for pre-installation testing • Screen out valves that will not perform as intended • Due to manufacturing faults or limits • Due to handling problems • Due to setting problems • Know actual valve characteristics • May be different than "typical" valve tested by VPC • Use actual characteristics in gas-lift programs • Evaluate various valves types/sources • If a given valve type/model is routinely unsatisfactory • If a used valve should not be re-run 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingBusiness Justification • Justification for post-installation testing • Evaluate valve condition • Can it be re-dressed and re-run, or • Should it be discarded • Learn • How well did the valve survive in the well's environment • Is a different valve type needed in this environment • Is a different valve metallurgy needed 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingHow the Tester Works • Quick, simple test of each gas-lift valve • Insert valve in test fixture – 1" and 1.5" available • Apply nitrogen pressure (from N2 bottle) • Conduct these tests, under computer control • Opening pressure • Closing pressure • Port leak rate • Load rate of bellows and/or spring • Maximum effective stem travel • Back check valve leak rate • Port/bellows ("R") ratio • Bellows failure and/or dome leak 2001 ASME/API Gas-Lift Workshop
AVT Front Panel 2001 ASME/API Gas-Lift Workshop
AVT Computer Control 2001 ASME/API Gas-Lift Workshop
Preparing to Test a Valve 2001 ASME/API Gas-Lift Workshop
Close Fixture, Connect Hose 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingHow the Tester Works • Quick, simple test of each gas-lift valve (con't) • Entire test of one valve takes about 3 minutes • Produces a report • Actual test results vs. operator-entered test criteria • A Pass or Fail is declared for each test • Produces a gas-lift valve performance plot • Actual performance plot of the tested valve vs. • Plot based on VPC (or standard) characteristics • Exports a file • Test results and actual valve characteristics can be exported to any gas-lift program • For example, Shell inputs results into WinGLUE 2001 ASME/API Gas-Lift Workshop
AVT Test Results Screen 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingIntended Operational Process • Routine testing of every gas-lift valve • Test every valve before it is run • If valve "passes" all tests, run it • If valve "fails" one or more tests, return it • Have one or more spares on hand • Store every test result in a gas-lift program and a database • Use in program for routine analysis • Use in database to learn, evaluate • Test every valve when it is pulled • Store results in database • Compare "after" performance with "before" 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingInitial Field Experience • Use of the AVT has…. • Increased accuracy of pressure and port leak measurements. • Extended the practice of testing gaslift valves to individuals who may not be familiar with typical shop practices. • Insures a consistently applied testing standard. The technician cannot “help” the valve pass a test. 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingInitial Field Experience • Use of the AVT has… • Found that good valves re-test consistently. • Provided the technician, engineer, and wireline operator with a “certificate” indicating the valve has passed all tests. • Provided a link from the gaslift shop to the engineers desk. 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingInitial Field Experience • Camco BKR-5 valves were tested for Brunei Shell Petroleum in Seria, Brunei • The tested R ratio was MUCH larger than the manufacturer’s published R ratio. • Valves with 3/16” TC ports tested with R ratios of .154. The printed R ratio is .118. • This means the valve will have approximately 30% more casing sensitivity than expected. 2001 ASME/API Gas-Lift Workshop
Chamfered TC Port 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingInitial Field Experience • Camco BKR-5 valves were tested for Brunei Shell Petroleum in Seria, Brunei • Back checks do not seal leak tight. • The AVT found several valves with bad O-rings on the seat. • The AVT found 1 valve with a leaking tail plug. • The AVT found several valves with leaking O-rings at the valve body joints. 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingInitial Field Experience • Camco BKR-5 valves were tested for Brunei Shell Petroleum in Seria, Brunei • The loadrate was generally less than 1300 psig/inch. This is expected for valves set at pressures less than 1000 psig. • The effective stem travel was generally less than 0.100 inch. This is less than expected but enough for a 3/16” ported valve with an 8 or 10 choke. 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingOutstanding Issues • There is more work to be done • Initial valve tester is a prototype • Needs to be re-packaged into a fully field-worthy device • It may be possible to use the tester to help conduct some VPC tests • Needs to be evaluated 2001 ASME/API Gas-Lift Workshop
Routine Valve TestingConclusions • This is one more step forward for gas-lift • There is now a cost-effective way to test every gas-lift valve • Before it is run • After it has been pulled • This should greatly improve quality assurance and reduce "infant mortality" that comes from running valves that are not properly suited: • Manufacturing faults • Handling problems • Setting problems 2001 ASME/API Gas-Lift Workshop