In the May 2014 issue of Flow Control magazine, I addressed the new standard, API 624 "Type Testing of Rising Stem Valves Equipped with Graphite Packing for Fugitive Emissions, First Edition." This standard, which was published and put into effect in February, establishes guidelines for testing industrial valves for emissions compliance. Since the publication of the article, further requests from industry have spurred the creation of another specification, API 641 "Type Testing of Quarter-Turn Valves," and an API “Piping and Valves” committee has been formed. Regulators and end-users are also working on:
Valve emissions by supplier outside of the U.S. Supplier names are withheld. (Source: Fluor Canada)
How much of an impact will API 624 have on valve emissions. (Source: Fluor Canada)
Geographical trends in valve emissions. (Source: Fluor Canada)
1. ISO15848 “Measurement, test and qualification procedures for fugitive emissions”
– Part I – “Classification system and qualification procedures for type testing of valves”
– Part II – “Production acceptance test of valves”
2. API 622, “Type Testing of Process Valve Packing for Fugitive Emissions”
3. End-user defined fugitive emission reduction requirements
Key aspects of valve testing per API 624 include:
– The standard covers rising and rising-rotating stem valves up to 24” diameter.
– Class 1500# valves are not covered.
– The test medium is methane.
– Test cycles required are 310 in total with three thermal cycles.
– Temperature application range is from -29 C to 538 C, with last cycle 10 cycles user defined (can be -45 C).
– Re-tightening of gland bolts is not permitted during test.
– Valve stem test orientation is vertical.
– Several valves must be tested to achieve API 624 compliance. Similar industry principles applied to test valves qualify two nominal sizes smaller, one size larger, and one pressure class below.
– Allowable leakage is 100 PPM maximum.
– Gate and globe valves need to be tested separately. For example, Gate Valves per API602, four tests; API600, eight tests (up to 20” diameter); API 603, eight tests; and for Globe Valves per API 602, four tests.
– Test valves should be production valves, not specially manufactured test valves.
As a result of the release of API 624, testing companies have been gearing up for an increase in the number and size of test valves, and new test houses are coming to market.
Implementation of API 624 needs to be carefully monitored, and claims from valve manufacturers should be validated by requesting to view test results. Important factors to be mindful of include:
– Number of cycles on some valves could be detrimental to packing, as certain smaller size valves don’t come with grease ports to keep the stem lubricated all of the time.
– Failures of valve stem threads, yokes and glands during test.
– Grease traps into packing and causes leakage.
– At higher temperatures a few greases create volatile organic compound and burn off.
– Testing in vertical generates more heat in yoke area.
A preliminary survey was conducted with end-users regarding current utilization and application of API 624. Results are summarized in the following table.
|End-User||Have you adapted API 624?||Are you updating your existing specifications and adding API 624 requirements?||Is API 624 beneficial to your plants?||Are you conducting plant surveys on Valve Fugitive Emissions?||Are you applying API 624 to exisiting Valves?||How are you applying API 624 to your plants?|
|1.||YES, 100% for USA, but in part for Rest of World||YES, for new valves only||YES, but may reduce number of valve tests||YES||All valves leaking 500 PPM would be retrofitted during shutdown period in-line||We are applying API 624|
|2.||NO, only when/if API 624 expands to include end-users needs outside of the petroleum industry||NO||NO||YES||NO||NO|
|3.||No, in works sometime before the end of 2014||YES||YES||In planning stage||In planning stage||In planning stage|
|4.||NO, as currently putting togther a technical qualification on process on API 624.||YES, already updated in our valve specification to comply 100 PPM leakage rate requiements per API 624.||YES, this will be incorporated in testing standard for valves that will be installed in citical service.||YES, our leakage limit is 7 PPM HRS at one meter and our process contains an avg. of 17% H2S in hydrocarbon. We use infrared cameras for our monitoring program.||YES, we are encouraged by local authorities and government to implement a fugutive emissions and leak detection and repair progam within next year or two||All valves pulled out of service for repair are having the packing replaced with spool packing from a packing manufacurer where the API 622 test result did not exceed 5 PPM. We are installing this packing in all service not just VOC service.|
|5.||NO, we have not yet fully documented the requirement for compliance with API 624 into our corporate technical standards, by 2015 earliest.||YES, partially, we have added the requirement in our corporate technical standard that "All valves must achieve a 100 PPM max. packing leakage to meet EPA Method 21." We have not yet made specific reference to API 624.||YES||YES, partitially our USA plans have an LDAR procedure in place to ensure that all valves meet max. leakage rates per U.S. EPA requirements||Our Canadian Operations currently do not have a formal corporate procedure–each of our Canadian facilities have varying levels of such procedures, which are being reviewed for consolidation to a corporate standard procedure.||Our USA Plant, through our LDAR Procedure will repair all valves to meet EPA max. leakage.|
|6.||YES, all new valve manufacturers applying to get on our AML will have to complete this testing.||Not sure as this is not my area.||YES||Not sure, as this is handled by Envionmental and the individual plants.||Not sure, as this is handled by Envionmental and the individual plants.||Not sure, as this is handled by Envionmental and the individual plants.|
|7.||NO||NO||NO||YES||NO||Not doing this.|
|8.||NO||No sure.||We will.||YES||NO||No action yet.|
|9.||NO||Specificiation aleady included the 100 PPM requirement.||YES||YES||YES||Currently not applying.|
Gobind Khiani, P.Eng., is with Fluor Canada Ltd. Khiani has spent 20-plus years in the energy and power business and has worked in three countries (United Kingdom, Dubai and Canada) with 10-plus years in Western Canadian Oil and Gas Industry based out of Calgary, Alberta. He graduated from University of Poona in India and earned his master’s degree in Materials and Mechanical Engineering from Schulich School of Engineering at University of Calgary, Alberta, Canada. He is a registered professional engineer in the provinces of Alberta and Saskatchewan. His specialties are Mechanical Static Equipment Integrity, Quality, Energy Asset Management, Greenhouse Gases (Energy Efficiency), and Facility Engineering Management. Khiani can be reached at 403 850-6982 or firstname.lastname@example.org. Connect with him at ca.linkedin.com/in/gobindkhiani.