Control Valve Leakage Class (ANSI FCI 70-2)
Вставка
- Опубліковано 19 жов 2024
- The term “Control Valve Seat Leakage Class” comes from ANSI / FCI 70-2. This is a control valve seat leakage specification Standard.
( 🔴 ) Link to FREE Udemy Course for I&C Professionals
1500+ Engineers have taken the Course
(Engineers have said it is even BETTER than the PAID Courses available)
Give it a Try 😊
Link 👉 asad-shaikh-in...
Valve Leakage Classifications
Class I - Valve Leakage Classifications Identical to Class II, III, and IV in construction and design intent, but no actual shoptest is made. Class I is also known as dust tight and can refer to metal or resilient seated valves.
Class II - Valve Leakage Classifications Intended for double port or balanced singe port valves with a metal piston ring seal and metal to metal seats.
• 0.5% leakage of full open valve capacity.
• Service dP or 50 psid (3.4 bar differential), whichever is lower at 50 to 125oF.
• Test medium air at 45 to 60 psig is the test fluid.
Typical constructions:
• Balanced, single port, single graphite piston ring, metal seat, low seat load• Balanced, double port, metal seats, high seat load
Class III - Valve Leakage Classifications Intended for the same types of valves as in Class II.
• 0.1% leakage of full open valve capacity.• Service dP or 50 psid (3.4 bar differential), whichever is lower at 50 to 125oF.
• Test medium air at 45 to 60 psig is the test fluid.
• Balanced, double port, soft seats, low seat load
• Balanced, single port, single graphite piston ring, lapped metal seats, medium load
Class IV - Valve Leakage Classifications
Intended for single port and balanced single port valves with extra tight piston seals and metal to-metal seats.
• 0.01% leakage of full open valve capacity.
• Service dP or 50 psid (3.4 bar differential), whichever is lower at 50 to 125oF.
• Test medium air at 45 to 60 psig is the test fluid.
Typical constructions:
• Balanced, single port, Teflon piston ring, lapped metal seats, medium seat load
• Balanced, single port, multiple graphite piston rings, lapped metal seats
• Unbalanced, single port, lapped metal seats, medium seat load
• Class IV is also known as metal to metal
Class V - Valve Leakage Classifications
Intended for the same types of valves as Class IV.
• The test fluid is water at 100 psig or operating pressure.
• Leakage allowed is limited to 5 x 10 ml per minute per inch of orifice diameter per psi differential.
• Service dP at 50 to 125 oF.
Typical constructions:
• Unbalanced, single port, lapped metal seats, high seat load
• Balanced, single port, Teflon piston rings, soft seats, low seat load
• Unbalanced, single port, soft metal seats, high seat load
Class VI - Valve Leakage Classifications
Class VI is known as a soft seat classification.
Soft Seat Valves are those where the seat, shut-off disc or both are made from some kind of resilient material such as Teflon. Intended for resilient seating valves.
• The test fluid is air or nitrogen.
• Pressure is the lesser of 50 psig or operating pressure.
• The leakage limit depends on valve size and ranges from 0.15 to 6.75 ml per minute for valve sizes 1 through 8 inches.
🔴Link to Instrumentation Crash Course for Professionals (FREE course)
1500+ Students have already taken this course.
👉asad-shaikh-instrumentation.ck.page/06e66ac455
Students have said to make the course course PAID (Because of the value they received from the course)
Let me know your feedback
Wonderful video !!
Thanks Asad. Very useful insite on the topic
Very Informative !! Please also make video on leakage class requirement for on-off valves...Thanks!!!
Thanks Prashant !! Yes sure . !! 😊
Thanks
Most welcome 😊