Type 299 Pressure Reducing Regulators

Transcription

1 Type 299 Pressure Reducing Regulators Fisher, Fisher-Rosemount, and Managing The Process Better are marks owned by Fisher Controls International, Inc. or Fisher-Rosemount Systems, Inc. All other marks are the property of their respective owners. D02308X02 Fisher Controls International, Inc. 996; All Rights Reserved, 9/96

2 Type 299 Pressure Reducing Regulator Features D Wide Variety of Applications Natural gas distribution systems, gas supplyto industrial boilers, furnaces, ovens, mixers, plant air service. D Not an adaptation of existing regulators New design of intergrated cases and internal registration ports. D H ig h -C a p a c ity P re s s u re C o n tro l Actuator diaphragm responds quickly to downstream pressure change, causing immediate correction in main valve position. Pilot responds simultaneously and controls final positioning of main valve. This action permits full main valve travel, resulting in higher capacity than could be obtained without a pilot. D Reusable O-rings At All Servicable Joints No gaskets. D Accuracy Keeps constant inlet pressures to downstream equipment by accurately controlling distribution system pressures at widely varying flow rates and supply pressures for maximum efficiency and best operation, or by eliminating the need for pressure-compensating meters by holding a steady pressureto the meter inlet. D Compact in Size Small envelope because of the built in pilot and internal registration. OUTLET D Rugged Construction Cast aluminum casings, steel bodies. Two bolt connection of the regulator to the body, no union ring. D Easy Registration Conversion Two screws and O-rings to change internal registration to external or dual registration. DOWNSTREAM CONTROL LINE D Fewer Parts Reduces parts inventory (recommended parts) only one closing spring. D Easy Startup No special procedure required. D Economical, Labor-Saving Installation Supply pressure to pilot is factory-piped directly from inlet side of main regulator body, thus requiring no upstream pilot supply line on standard installations. D Easy to Maintain Main valve disk and orifice can be inspected without removing body from pipeline. Easy access two bolt flange permits quick removal of actuator and pilot from body. PILOT D No Atmospheric Bleed Loading pressure bleeds downstream through pilot via bleed restriction and downstream control line. No bleed occurs when regulator is shut off. D Highest Quality Designed and manufactured to ISO 900 standards 2

3 Specifications Body Size And End Connection Styles --inch, 2-inch NPT screwed or, 2-inch ANSI Class 25 and 250 flanged Orifice Sizes and Maximum Allowable Inlet Pressure () /4 x -inch (0.3 ) -inch (0.3 ) -inch (0.3 ) -inch (8.6 ) -inch (4. ) -inch (2.8 ) Outlet (Control) Pressure Ranges (, 2) See Table Pressure Control Accuracy +/ % of absolute control pressure Minimum Differential Pressure For Full Stroke.5 psi (0.0 ) Maximum Emergency Outlet Pressure () 45 (3. ) Flow Coefficients See Table 2 Typical Regulating Capacities See Tables 3 to 5 Construction Materials Actuator Upper Casing: Aluminum (A03800) Actuator Lower Casing: Aluminum (A03800) Bulletin 7.2:299 Pilot Spring Case: Aluminum (A03800) Actuator Diaphragm: Nitrile Pilot Diaphragm: Nitrile Pilot Inlet Screen: 8 8 stainless steel Valve Body: Cast iron, or steel Orifice and Valve Stem: Aluminum (A9207) Disk Holder: Aluminum (A9207)/nitrile Main Disk Construction: Nitrile Metal Trim Parts For Pilot: Steel, stainless steel, or aluminum Pilot Disk Construction: Nitrile O-Rings: Nitrile Fittings And Tubing: Steel/stainless steel (std), brass/copper, or stainless steel Approximate Weight 2 lbs (9.5 kg) Temperature Capabilities () 20 to 50 F ( 29 to 65.5 C) Control Line And Pilot Connections: See Figure 5 Additional Options: Three fixed restriction sizes to choose from:.044-inch (.2 mm) red (std. gain).07-inch (.80 mm) green (low gain).082-inch (2.08 mm) blue (lower gain) Pressure loading regulator (3) : A Type 67AF with an internal 40 microns filter Filter (3) : A P590 Series filter installed in the pilot supply tubing between main body and pilot. The pressure/temperature limits in this bulletin and any applicable standard or code limitation should not be exceeded. 2. For optinum preformance, a pilot supply regulator may be installed in the pilot supply tubing between the main valve and pilot. 3. Only one (a pressure loading regulator or a P590 Series filter) may be ordered with the Type 299, but not both. Table. Outlet Pressure Ranges MAXIMUM RECOMMENDED PILOT SUPPLY PRESSURE 40 psi () (2.8 ) 50 psi (0.3 ) PILOT OUTLET (CONTROL) PRESSURE RANGE Free Length Part Number Color Code Inches (mm) 3.5 to 6 inches w.c. (9 to 5 m) 6 to 9 inches w.c. (5 to 22 m) 9 to 20 inches w.c. (22 to 49 m) 6 to 40 inches w.c. (40 to 99 m) to 3.25 (0.07 to 0.4 ) 3.25 to 6 (0.4 to 0.4 ) 6 to 6 (0.4 to.0 ) (.0 to 2.4 ). Use a pilot supply regulator if actual inlet pressure exceeds 40 psi (2.8 ). T3707T002 T3589T002 N32X002 B T3593T002 T367T002 T3600T002 Black Yellow Silver Purple Lt. Blue Orange Red Zinc.86 (47.2) 2.05 (52.0) 2.8 (55.4) 2.2 (53.8) 2.2 (53.8) 2.40 (6.) 2.0 (53.3) 2.5 (54.6) Wire Diameter Inches (mm) (.4) 0.05 (.3) (.9) (2.3) 0.05 (2.7) 0.20 (3.0) 0.42 (3.6) (5.3) Table 2. Flow Coefficients and Orifice Diameters ORIFICE DIAMETER FOR RELIEF SIZING REGULATING G C C INCH (mm) WIDE OPEN C g C g P < 0 psi P 0 psi /4 x (6.4 x 9.5)

4 B OUTLET J E D H C PILOT SUPPLY SCREEN DOWNSTREAM CONTROL LINE G F A PRESSURE OUTLET PRESSURE LOADING PRESSURE ATMOSPHERIC PRESSURE Figure 3. Operational Schematic of Type 299 Regulator (External Registration) Principle of Operation Letter keys in this section refers to figure 3 unless otherwise noted. Fast response and accuracy are made possible by the amplifying effect of the pilot and by the two-path control system. The function of the pilot is to sense change in the controlled pressure and amplify it into a larger change in the loading pressure. Any changes in outlet pressure act quickly on both the actuator diaphragm and the loading pilot, thus providing the precise pressure control that is characteristic of a two-path system. A typical pilot has an approximate gain of 50, which means the outlet pressure needs to droop only /50 as much as a self-operated regulator in order to obtain the same pressure differences across the main diaphragm. Advantagesof a pilot operated regulator are high accuracyand high capacity. Upstream or inlet pressure is utilized as the operating medium, which is reduced through pilot operation to load the main diaphragm chamber. Tubing connects the inlet pressure to the pilot. Downstream or outlet pressure registers underneath main diaphragm (E) and on top of pilot diaphragm (F). There are three different versionsof registration for the Type 299. a. Internal registration (screws (J) removed) Outlet pressure is registered through the throat to the main diaphragm chamber and then through a small port (G) to the top of the pilot diaphragm. b. External registration The throat is blocked by screws (J) and a downstream control line is connected to the pilot diaphragm chamber which is connected to the lower main diaphragm chamber by a small port (G). 4

5 c. Dual registration (screws (J) removed) The lower main diaphragm chamber registers outlet pressure through the throat and pilot diaphragm chamber registers downstream pressure by use of a downstream control line. The port (G) between the chambers is blocked by inserting a screw (J). In operation, assume the outlet pressure is less than the setting of pilot control spring (A). The top side of pilot diaphragm assembly (F) will have a lower pressure than the setting of spring (A). Spring (A) forces the diaphragm assembly upward, opening the pilot orifice (C). Additional loading pressure is supplied to the top side of main diaphragm (E). This creates a higher pressure on the top side of main diaphragm (E) than on the bottom side, forcing the diaphragm downward. This motion is transmitted through a lever, which pulls the valve disk open, allowing more gas to flow through the valve. When the gas demand in the downstream system has been satisfied, the outlet pressure increases. The increased pressure is transmitted through the downstream control line and acts on top of the pilot diaphragm (F). This pressure exceeds the pilot spring setting and forces the diaphragm down, closing orifice (C). The loading pressure acting on main diaphragm (E) bleeds to the downstream system through a bleed restriction (H). With a decrease in loading pressure on top of main diaphragm (E), main spring (B) exerts an upward force on the diaphragm post connected to main diaphragm (E), pulling it upward. This moves the main valve toward its seat, decreasing flow to the downstream system. Overpressuring any portion of a regulator or associated equipment may cause leakage, part damage, or personal injury due to bursting of pressurecontaining parts or explosion of accumulated gas. Regulator operation within ratings does not preclude the possibility of damage from external sources or from debris in the pipeline. A regulator should be inspected for damage periodically and after any overpressure condition. The pilot is provided with a /4-inch NPT tapped connection in the spring case. Monitoring Systems for Safety Monitoring regulators serve as overpressure protection devices to limit system pressure in the event of open failure of a working regulator feeding the system. A method of using Type 299 regulators in monitoring systems are as follows: Wide Open Monitor The control line of the upstream regulator is connected downstream of the second regulator (figure 4), so that during normal operation the monitoring regulator is standing wide open with the reduction to distribution pressure being taken across the working regulator. Only in case of open failure of the working regulator does the wide-open monitoring regulator take control at its slightly higher setting. The upstream regulator can easily be field converted or ordered with screws and O-rings in the throat (figure 3). This seals off the path that otherwise would let line pressure ahead of the working regulator inlet try to close the wide-open monitoring regulator. OPTIONAL PILOT SUPPLY REGULATOR Overpressure Protection Like most regulators, the Type 299 has outlet pressure ratings lower than the inlet pressure ratings. Complete downstream overpressure protection is needed if the actual inlet pressure exceeds the outlet pressure rating. OPTIONAL PILOT SUPPLY REGULATOR FLEXIBLE ARRANGEMENT THAT PERMITS WIDE-OPEN MONITOR TO BE EITHER UPSTREAM OR DOWNSTREAM Overpressure protection for internal parts is built into the main and pilot diaphragms by means of a small spring on each post. The springs will allow the diaphragms to move farther on the posts avoiding damage to or bending of the valve trim. WIDE-OPEN MONITOR WORKING REGULATOR OPTIONAL PILOT SUPPLY REGULATOR MINIMUM PIPING ARRANGEMENT THAT REQUIRES WIDE-OPEN MONITOR ALWAYS TO BE UPSTEAM Figure 4. Typical Wide-Open Monitor Installations 5

6 Capacity Information Tables 3 to 5 gives Type 299 natural gas regulating capacities at selected inlet pressures and outlet pressure settings. Flows are in scfh (60 F and 4.7 psia) of 0.6 specific gravity gas at 60 F. To determine equivalent capacities for air, propane, butane, or nitrogen, multiply the table 6 capacity by the following appropriate conversion factor: for air, for propane, for butane, or for nitrogen. For gases of other specific gravities, multiply the given capacity by and divide by the square root of the appropriate specific gravity. Then, if capacity is desired in normal cubic meters per hour (m 3 /hr) at 0 C and.0325, multiply scfh by To determine regulating capacities for pressures or constructions not given in tables 3 to 5, or to determine wide-open capacities for relief sizing at any inlet pressure, use the following formula and convert according to the factors in the preceding paragraph if necessary: where: C = C g /C v (See table 2) C g = Gas sizing coefficient (see table 2) G = Gas specific gravity (air =.0) P = Regulator inlet pressure, psia P = Pressure drop across regulator, psi Q = Gas flow rate, scfh T = Absolute temperature of gas at inlet, degree Rankine Note Due to boost, the above formula can not be used to obtain correct regulating capacities for regulators with internal registration. The published capacities were obtained using inlet and outlet piping the same size as the regulator body size. Pressure Registration Methods Internal use for easiest installation. Capacity is somewhat limited because of droop and /or boost associated with sensing pressure within the body. External use for higher capacity and /or upstream regulator in a monitor set. Capacity is increased because of better registration of pipeline pressure when a control line is used. The alternate -inch NPT control line connection can be used for piping convenience. Dual (internal plus external) use to improve performance over internal pressure registration when there is a low flow rate and high pressure drop and a large orifice (control line must be piped to the primary /4-inch NPT connection on the the pilot). Installation Although the actuator and pilot can be mounted in 90 increments relative to the body, the normal installation is with the body in a horizontal run of pipe and the pilot hanging vertically from the bottom of the actuator. Control and vent lines necessary for installation are not supplied with a Type 299 regulator. Control and vent connection locations are shown in figure 5. In many instances good piping practice will require that outlet piping be swaged up above the body size to prevent excessive pressure drop along the outlet line. The piping should be expanded as close to the regulator outlet as possible. Dimensional information also is given in figure 5. Ordering Information To order a particular construction specify the items listed below. In addition, any optional constructions must be specified. Application. Composition and specific gravity of gas (including chemical analysis if possible). 2. Range of temperatures, flowing inlet pressures (maximum, minimum, nominal), and pressure drops. 3. Desired outlet pressure setting. 4. Range of flow rates (minimum controlled, maximum, normal). 5. Piping size(s). 6. Tubing fitting material. 7. Pilot supply regulator or a P590 series filter option. 8. Internal or External registration. 9. Body material. 0. Body end connection. Construction Refer to the Specifications on page 3. Carefully review each specification and/or referenced tables, specify the desired selection whenever there is a choice to be made. 6

7 Table 3. Regulating Capacities For --inch and 2-inch External/Dual Registration in SCFH (60 F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. OUTLET PRESSURE PRESSURE ORIFICE SIZE, Inches (mm) RANGE AND SETTING, to 6 inches w.c (8.88 to 5 m) inch w.c (8.8 m) T3707T Black to 9 inches w.c (5 to 22 m) inch w.c (7.5 m) T3589T Yellow to 20 inches w.c (22 to 49 m) inch w.c (35 m) N32X Silver to 40 inches w.c (40 to 99 m) inch w.c (70 m) B Purple

8 Table 3. Regulating Capacities For --inch and 2-inch External/Dual Registration in SCFH (60 F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. (continued) OUTLET PRESSURE RANGE AND SETTING, PRESSURE ORIFICE SIZE, Inches (mm) to (0.07 to 0.4 ) (0.3 ) T3593T Light Blue to (0.4 to 0.4 ) psg (0.3 ) T367T Orange to (0.4 to.0 ) (0.7 ) T3600T Red to (0.4 to.0 ) psg (.0 ) T3600T002 Red (.0 to 2.4 ) (.4 ) Zinc

9 Table 3. Regulating Capacities For --inch and 2-inch External/Dual Registration in SCFH (60 F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. (continued) OUTLET PRESSURE PRESSURE ORIFICE SIZE, Inches (mm) RANGE AND SETTING, (.0 to 2.4 ) psg (.7 ) Zinc (.0 to 2.4 ) (2. ) Zinc (.0 to 2.4 ) (2.4 ) Zinc 9

10 Table 4. Regulating Capacities For -inch Internal Registration in SCFH (60 F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. OUTLET PRESSURE PRESSURE ORIFICE SIZE, Inches (mm) RANGE AND SETTING, to 6 inches w.c (8.88 to 5 m) inch w.c (8.8 m) T3707T Black to 9 inches w.c (5 to 22 m) inch w.c (7.5 m) T3589T Yellow to 20 inches w.c (22 to 49 m) inch w.c (35 m) N32X Silver to 40 inches w.c (40 to 99 m) inch w.c (70 m) B Purple

11 Table 4. Regulating Capacities For -inch Internal Registration in SCFH (60 F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. (continued) OUTLET PRESSURE PRESSURE ORIFICE SIZE, Inches (mm) RANGE AND SETTING, to (0.07 to 0.4 ) (0.3 ) T3593T Light Blue to (0.4 to 0.4 ) psg (0.3 ) T367T Orange to (0.4 to.0 ) (0.7 ) T3600T Red to (0.4 to.0 ) psg (.0 ) Zinc (.0 to 2.4 ) (.4 ) Zinc

12 Table 4. Regulating Capacities For -inch Internal Registration in SCFH (60_F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. (continued) OUTLET PRESSURE RANGE AND SETTING, PRESSURE ORIFICE SIZE, Inches (mm) (.0 to 2.4 ) (.7 ) Zinc (.0 to 2.4 ) (2. ) Zinc (.0 to 2.4 ) (2.4 ) Zinc OUTLET PRESSURE, INCHES OF W.C PSIG TYPE X 2INCH NPT BODY T3589T002 INCH ORFICE 7INCHES W.C. OUTLET PRESSURE SETTING 30 PSIG 40 PSIG OUTLET PRESSURE, mbar A6898 / IL FLOW RATE, SCFH OF 0.6 SPECIFIC GRAVITY NATURAL GAS 7 Figure 5. Typical 7Inches (7 m) W ater Column Performance Curves 2

13 Table 5. Regulating Capacities For 2-inch Internal Registration in SCFH (60 F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. OUTLET PRESSURE RANGE AND SETTING, PRESSURE ORIFICE SIZE, Inches (mm) to 6 inches w.c (8.88 to 5 m) inch w.c (8.8 m) T3707T Black to 9 inches w.c (5 to 22 m) inch w.c (7.5 m) T3589T Yellow to 20 inches w.c (22 to 49 m) inch w.c (35 m) N32X Silver to 40 inches w.c (40 to 99 m) inch w.c (70 m) B Purple

14 Table 5. Regulating Capacities For 2-inch Internal Registration in SCFH (60 F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. (continued) OUTLET PRESSURE PRESSURE ORIFICE SIZE, Inches (mm) RANGE AND SETTING, to (0.07 to 0.4 ) (0.3 ) T3593T Light Blue to (0.4 to 0.4 ) psg (0.3 ) T367T Orange to (0.4 to.0 ) (0.7 ) T3600T Red to (0.4 to.0 ) psg (.0 ) Zinc (.0 to 2.4 ) (.4 ) Zinc

15 Table 5. Regulating Capacities For 2-inch Internal Registration in SCFH (60_F and 4.7 psia) of 0.6 Specific Gravity Natural Gas. (continued) OUTLET PRESSURE RANGE AND SETTING, PRESSURE ORIFICE SIZE, Inches (mm) (.0 to 2.4 ) (.7 ) Zinc (.0 to 2.4 ) (2. ) Zinc (.0 to 2.4 ) (2.4 ) Zinc TYPE X 2INCH NPT BODY 5 PSIG OUTLET PRESSURE SETTING INCH ORFICE T367T OUTLET PRESSURE, PSIG PSIG 20 PSIG 30 PSIG 50 PSIG 60 PSIG OUTLET PRESSURE, BAR A6899 / IL FLOW RATE, SCFH OF 0.6 SPECIFIC GRAVITY NATURAL GAS Figure 6. Typical 5 PSIG (0.34 ) Performance Curve 5

16 A 4.9 (24) 3. (79) 4.3 (09) /4 8 NPT VENT /4 8 NPT CONTROL LINE CONNECTION 8.6 (28) 2. (307) FILTER OPTION 3.7 (348) 4 NPT ALTERNATIVE CONTROL LINE CONNECTION 5.8 (47) PILOT SUPPLY FILTER REGULATOR OPTION 7.6 (93) 7.9 (20) INCH (mm) BODY A T382 C / IL NPT X NPT 2 NPT X 2 NPT 2 IN CLASS 25 FF FLG 2 IN CLASS 250 RF FLG 6.2 (55) 6.2 (55) 0.00 (254) 0.50 (267) Figure 7. Type 299 Dimensions The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. We reserve the right to modify or improve the designs or specifications of such products at any time without notice. For information, contact Fisher Controls: Marshalltown, Iowa 5058 USA Cernay France Sao Paulo Brazil -Singapore 052 Printed 6 in U.S.A.