ANSI FCI 70-3-2016 REGULATOR SEAT LEAKAGE.pdf

1、 ANSI/FCI 70-3-2016 AMERICAN NATIONAL STANDARD REGULATOR SEAT LEAKAGE Fluid Controls Institute, Inc. Sponsor: Fluid Controls Institute, Inc. 1300 Sumner Ave Cleveland, Ohio 44115-2851 iiANSI/FCI 70-3-2016 AMERICAN NATIONAL STANDARD Regulator Seat Leakage Sponsor Fluid Controls Institute, Inc. iiiCON

2、TENTS PAGE Foreword iv 1. Purpose 1 2. Scope and Limitations 1 3. Definitions .1 4. Leakage Specifications and Classes . 1 5. Test Procedures . 2 6. References 3 Tables Table 1 2 Table 2 3 ivForeword (This foreword is included for information only and is not part of ANSI/FCI 70-3-2016, Regulator Sea

3、t Leakage.) This voluntary standard has been compiled and issued in the public interest. It is intended to eliminate present misunderstandings and to assist and guide those people involved in the specification, use or manufacture of regulators. The standard was developed by the FCI Regulator Section

4、 in 2001 and approved in 2004. The section revised the standard in 2014. The existence of a Fluid Controls Institute (FCI) standard does not in any respect preclude any member or non-member from manufacturing or selling products not conforming to this standard nor is the FCI responsible for its use.

5、 This standard is similar to ANSI/FCI 70-2 but eliminates the Class V test as regulators normally do not require this intermediate leakage class between Class IV and VI; however, in order to harmonize the classes between regulators and control valves, we kept the same leakage requirements within eac

6、h class. In 2015, the Regulator Section agreed to add a Class VIII to the standard. This class establishes a “no permissible leakage“ standard generally associated with resilient seating regulators either balanced or unbalanced with “O“ rings or other gapless seals. FCI recognizes the need to period

7、ically review and update this standard. Suggestions for improvement should be forwarded to the Fluid Controls Institute, Inc., 1300 Sumner Avenue, Cleveland, Ohio 44115-2851. All constructive suggestions for expansion and revision of this standard are welcome. Please go to the FCI web site for all o

8、f the latest technical articles and standards. 1ANSI/FCI 70-3-2016 AMERICAN NATIONAL STANDARD Regulator Seat Leakage 1. PURPOSE 1.1 This standard establishes a series of seat leakage classes for regulators and defines the production test procedures. 2. SCOPE & LIMITATIONS 2.1 This standard applies t

9、o pilot operated and direct acting pressure reducing, pressure relieving (back pressure), differential pressure and temperature regulators. 2.2 Selection of a leakage class is not restricted as to regulator design, but acceptable values for various commercially available designs are suggested for ea

10、ch class under Section 4. 2.3 The standard cannot be used as a basis for predicting leakage at conditions other than those specified. 2.4 This standard is similar to ANSI/FCI 70-2 Control Valve Seat Leakage. 3. DEFINITIONS 3.1 Regulator. A self-contained valve operated by the flowing fluid or by the

11、 process energy from a directly connected sensing device. 3.2 Cv- An experimentally determined valve sizing coefficient. (Ref. ISA S75.01.01, ISA S75.02.01 and FCI Standard 84-1). 3.3 Lockup (Dead End Shutoff). The deviation of the controlled variable from set point obtained at a no flow position. 3

12、.4 Maximum Capacity The flow rate at maximum travel generally used for safety or relief valve sizing. 3.5 Maximum Cv. Maximum Cvis Cvat maximum capacity calculated per ISA S75.01 generally used for safety relief valve sizing. For pilot-operated regulators maximum Cvincludes the Cvof the pilot. 3.6 M

13、aximum Travel. The regulator travel in the fully open position at the maximum design travel corresponding to maximum capacity. 3.7 Seat Leakage. The quantity of test fluid passing through an assembled regulator in the closed or locked up (shutoff) position under the test conditions as defined. 3.8 N

14、ominal Seat Diameter. Basic diameter used to determine maximum allowable seat leakage (Leakage Class VI). This is also referred to as port diameter or orifice diameter (of the seat ring). It should be noted that this is not the same as NPS. 4. LEAKAGE SPECIFICATIONS & CLASSES 4.1 The maximum allowab

15、le seat leakage as specified for each class shall not exceed the seat leakage in Table 1 using the test procedure as defined in Section 5. For Classes II through VIII each and every regulator shall be tested. The Cvof the pilot must be included. 4.2 Leakage Classes 4.2.1 CLASS I. A modification of a

16、ny Class II, III or IV regulator where the design intent is the same as the basic class, but by agreement between user and supplier, no test is required. 4.2.2 CLASS II. This class establishes the maximum permissible leakage generally associated with commercial double-seat regulators with metal-to-m

17、etal seats. 4.2.3 CLASS III. This class establishes the maximum permissible leakage generally associated with Class II (4.2.2), but with a higher degree of seat and seal tightness. 4.2.4 CLASS IV. This class establishes the maximum permissible leakage generally associated with commercial unbalanced

18、single-seat regulators with metal-to-metal seats. 4.2.5 CLASS VI. This class establishes the maximum permissible seat leakage generally associated with resilient seating regulators either balanced or unbalanced with “O” rings or similar gapless seals. 24.2.6 CLASS VII. This class establishes the max

19、imum permissible seat leakage generally associated with Class VI (4.2.5), but with test performed at the maximum operating differential pressure. 4.2.7 CLASS VIII This class establishes a no permissible leakage standard generally associated with resilient seating regulators either balanced or unbala

20、nced with “O” rings or other gapless seals. TABLE 1 Leakage Class Maximum Seat Leakage Class I (See 4.2.1) See Paragraph 4.2.1 Class II (See 4.2.2) 0.5% of maximum CvClass III (See 4.2.3) 0.1% of maximum CvClass IV (See 4.2.4) 0.01% of maximum CvClass VI (See 4.2.5) Leakage per Table 2 as expressed

21、in ml per minute versus seat diameter Class VII (See 4.2.6) Leakage per Table 2 as expressed in ml per minute versus seat diameter Class VIII (See 4.2.7) No observable bubbles for a period of one (1) minute using test methodology in Note (1) in Table 2. 5. TEST PROCEDURES Warning: Provisions should

22、be made to avoid overpressure in measuring devices resulting from inadvertent opening of the valve plug. 5.1 Test medium shall be clean air or nitrogen gas at 10-51C (50-125F). 5.2 Test Pressure or Temperature 5.2.1 Reducing Regulator 5.2.1.1 Reducing Regulator Class II-VI The pressure of the test m

23、edium shall be 3-4 bar (45-60 psig) or the maximum operating differential pressure, whichever is less. 5.2.1.2 Reducing Regulator Class VII For regulators with normal operating differentials less than 17 bar (250 psig), the pressure of the test medium shall be the maximum operating differential pres

24、sure or 3.5 bar (50 psig), whichever is greater. For regulators with normal operating differentials greater than 17 bar (250 psig), the pressure of the test medium shall be 17 bar (250 psig) unless otherwise agreed to with the customer. 5.2.1.3 Reducing Regulator Class VIII The pressure of the test

25、medium shall be 3-4 bar (45-60 psig) or the maximum operating differential pressure, whichever is less. 5.2.2 Back Pressure Regulator 5.2.2.1 Back Pressure Regulator Class II-VI The pressure of the test medium shall be 90-98% of the pressure defined by the first detectable flow or 3-4 bar (45 to 60

26、psig), whichever is less. 5.2.2.2 Back Pressure Regulator Class VII The pressure of the test medium shall be 95-98% of the pressure defined by the first detectable flow. 5.2.2.3 Back Pressure Regulator Class VIII The pressure of the test medium shall be 95-98% of the pressure defined by the first de

27、tectable flow. 5.2.3 Temperature Regulator 5.2.3.1 Temperature Regulator Class I-VI The test temperature must be within 10% of the set temperature (F) or the unit may be tested by applying air pressure (or vacuum) to the actuator to simulate a closed valve before the fill medium is added. 35.2.3.2 T

28、emperature Regulator Class VII The test temperature must be within 5% of the set temperature (F). 5.2.3.3 Temperature Regulator Class VIII The test temperature must be within 5% of the set temperature (F). 5.3 Leakage flow data shall be accurate to +/- 10% of reading. Pressure and temperature data s

29、hall be accurate to +/- 1% of reading. 5.4 The test fluid shall be applied to the normal or specified regulator body inlet. The regulator body outlet shall be connected to a suitable measuring device. 5.5 The regulator shall be adjusted to meet the operating conditions specified. The full normal clo

30、sing thrust as applied by air pressure, a spring, or other means shall then be applied. No allowance or adjustment shall be made to compensate for any increase in seat load obtained when the test differential is less than the maximum regulator operating differential pressure. 5.6 The leakage rate th

31、us obtained can then be compared to the calculated values for Classes II, III and IV in Table 1 or the values in Table 2 for Classes VI and VII. TABLE 2Nominal Seat Diameter (See 3.8) Millimeters (Inches) Standard ml per Minute (3)Bubbles per Minute(1) 25 (1)* 0.15 1(2)38 (1.5) 0.30 2 51 (2) 0.45 3

32、64 (2.5) 0.60 4 76 (3) 0.90 6 102 (4) 1.70 11 152 (6) 4.00 27 203 (8) 6.75 45 250 (10) 11.1 - 300 (12) 16.0 350 (14) 21.6 - 400 (16) 28.4 Notes: (1) Bubbles per minute as tabulated are a suggested alternative based on a suitable calibrated measuring device in this case a 6 mm (0.24 inch) O.D. x 1 mm

33、 (0.04 inch) wall tube submerged in water to a depth of from 3 to 6 mm (0.12 to 0.24 inch). The tube end shall be cut square and smooth with no chamfers or burrs and the tube axis shall be perpendicular to the surface of the water. Other apparatus may be constructed and the number of bubbles per min

34、ute may differ from those shown as long as they correctly indicate the flow in ml per minute. (2) If the valve seat diameter differs by more than 2 mm (0.08 inch) from one of the values listed, the leakage rate may be obtained by interpolation assuming that the leakage rate varies as the square of t

35、he seat diameter. (3) Standard milliliters based on 15.6 C (60 F) and 1 bara (14.73 psia). 6. REFERENCES 6.1 Fluid Controls Institute Standard, ANSI FCI 70-2, Control Valve Seat Leakage 6.2 Fluid Controls Institute, FCI 86-2, Regulator Terminology 6.3 The International Society of Automation, ANSI/IS

36、A S75.02.0,1Control Valve Capacity Test Procedures 6.4 The International Society of Automation, ISA 75.01.01,Flow Equations for Sizing Control Valves 6.5 CEN European Committee for Standardization, EN 334, Gas Pressure Regulators for Inlet Pressures up to 100 bar 4FCI REGULATOR & CONTROL VALVE ADDIT

37、IONAL STANDARDS ANSI/FCI 70-2, Control Valve Seat Leakage FCI 87-2, Power Signal Standard for Spring Diaphragm Actuated Control Valves ANSI/FCI 91-1, Standard for Qualifications of Control Valve Stem Seals FCI 84-1, Metric Definition of the Valve Flow FCI 70-1, Standard Terminology and Definition fo

38、r Filled Thermal Systems for Remote Sensing Temperature Regulators ANSI/FCI 79-1, Standard for Proof of Pressure Ratings for Pressure Regulators and Temperature Regulators FCI 86-2, Regulator Terminology FCI 99-2, Pressure Reducing Regulator Capacity FCI 99-3, Standards for Backpressure Regulator Ca

39、pacity FCI 4-1, Pressure Regulator Hydrostatic Shell FCI REGULATOR CONTROL VALVE TECHNICAL BULLETINS Tech Sheet #CVR 401 Insulation Systems Used as External Treatment for Control Valve and Regulator Noise Tech Sheet #CVR 402 Fundamental Principles of Self-Operated Pressure Reducing Regulators Tech Sheet #CVR 403 Laminar Flow Valve Sizing Made Easy Tech Sheet #CVR 404 Simple Reference Guide: Differences Between Direct and Pilot- Operated Regulating Valves