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HomeMy WebLinkAboutFlow - TAB 4 - Dwyer RM Style Flow Meter cutVISIT OUR WEBSITES: www.dwyer-inst.com • www.dwyer-inst.co.uk • www.dwyer-inst.com.au 161Flow The Rate-Master®flowmeter line of direct reading precision flowme- ters incorporates many unique user features at moderate cost. These low cost flowmeters are ideal for general use. Easy to read design — The direct reading scales eliminate troublesome conversions. The scales are brushed aluminum, coated with epoxy and the graduations are on both sides of the indicating tube. Special integral flow guides stabilize the float throughout the range to keep it from hunt- ing or wandering in the bore. The float is highly visible against a white background. Construction assures accuracy — All Rate-Master®flowmeter bodies are injection molded of tough, clear, shatter-proof polycarbonate plastic around a precision tapered pin. The result is accurate and repeatable readings. The single piece plastic body is mounted to a stainless steel back bone into which pipe thread inserts are welded to absorb piping torque. Precision metering valves of brass or stainless steel (specify BV or SSV on order) are available as an optional extra and permit precise flow ad- justments. For vacuum applications, Model RMA units are available with top mounted valves (specify TMV). The small Series RMA models are ac- curate within ±4% of full scale reading; Series RMB within ±3%; large Se- ries RMC within ±2%. Model RMC-SSV10" scale, 153⁄8" high Model RMB-SSV 5" scale, 83⁄4" high Model RMA-SSV 2" scale, 413⁄16" high Rate-Master® Flowmeters Polycarbonate, Gas Flow from .1-1800 SCFH, Water Flows to 10 GPM Series RM F A B C JBACK WIDTH K D E G H IFULL OPEN L Installation is simple — The Rate-Master®Flowmeter can be neatly panel mounted to keep flow tube centers in the same plane as the panel surface or surface mounted on the panel by means of tapped holes in the backbone. When through-panel mounted, the bezel automatically posi- tions the instrument at the correct depth in the panel cutout. Surface mounted units can also be held in place by the piping. All mounting hard- ware plus installation and operating instructions are included. Easy-to-Interchange bodies — Within a given Series Rate-Master® flowmeter bodies can be instantly interchanged. Simply “unplug” the body from backbone and replace it with another. “O” rings provide a tight seal on inlet and outlet. Piping remains undisturbed. Interchangeability is useful where different scale ranges are sometimes required at the same location in the laboratory or plant. Cleaning is easy — To release the plastic flowmeter body from the stainless steel backbone, just remove four screws. Pipe thread flow con- nections remain undisturbed. Remove the slide cover and the plug ball stop, clean the flow tube with soap and water and reassemble. It’s that simple. DIMENSION IN INCHES Model RMA A B C D E F G H I (OPEN) J K L 49⁄16 3 1⁄8NPT Conn. 15⁄8 10-32 Thds. 3⁄8 11⁄16 13⁄16 3⁄4 1 13⁄8 3⁄4 413⁄16 1 Model RMB 81⁄2 67⁄16 1⁄4NPT Conn. 315⁄16 1⁄4-20 Thds. 5⁄8 17⁄8 13⁄4 1 17⁄16 113⁄16 11⁄4 83⁄4 11⁄2 Model RMC 151⁄8 121⁄4 1⁄2NPT Conn. 83⁄4 3⁄8-24 Thds. 1 23⁄4 21⁄4 17⁄16 131⁄32 21⁄2 2 153⁄8 21⁄4 (BV or SSV MODELS ONLY) pg161 7/21/06 11:15 AM Page 1 CALL TO ORDER: U.S. Phone 219 879-8000 • U.K. Phone (+44) (0)1494-461707 • Asia Pacific Phone 61 2 4272-2055 162 Flow CAUTION Model RMA-2" Scale Model RMB-5" Scale Model RMC -10" Scale Range SCFH Air .05-.5 .1-1 .2-2 .5-5 1-10 2-20 5-50 10-100 15-150 20-200 CC Air/min. 5-50 10-100 30-240 50-500 100-1000 200-2500 LPM Air .5-5 1-10 2-25 5-50 5-70 10-100 CC Water/min. 5-50 10-110 20-300 Gal.Water/hr 1-11 2-24 4-34 5-50 Range No. 1 2 3 4 5 6 7 8 9 10 151* 150* 11 12 13 14 26 21 22 23 24 25 32 33 34 42 43 44 45 Range SCFH Air .5-5 1-10 3-20 4-50 10-100 20-200 40-400 50-500 60-600 Gal. Water per hour 1-12 1-20 4-40 10-100 SCFH & LPM Air 1.2-10/0.6-5 3-20/1.5-9.5 4-50/2-23 10-100/5-50 20-200/5-95 GPH & LPM Water 1-12/0.06-0.76 1-20/0.065-1.25 10-100/0.8-6.2 Range No. 4+ 50 51 52 53 54 55 56 57 82 83 84 85 50D 51D 52D 53D 54D 82D 83D 85D Range SCFH Air 5-50 10-100 20-200 40-400 60-600 100-1000 120-1200 200-1800 SCFM Air 1-10 2-20 4-30 Gal. Waterper hour 2-20 8-90 Gal.Water per minute .1-1 .2-2.2 .4-4 .8-7 1.2-10 Range No. 101 102 103 104 105 106 107 108 121 122 123 134 135 141 142 143 144 145 Dwyer®Rate-Master®flowmeters are designed to provide satis- factory long term service when used with air, water, or other com- patible media. Refer to factory for information on questionable gases or liquids. Caustic solutions, anti-freeze (ethylene glycol) and aromatic solvents should definitely not be used. Top Mounted Metering Valves – Same precision construction for vacuum applications. RMA mod- els only. Specials — Special ranges, scales, mounting arrangements, etc., are available on special order, or in OEM quantities. SPECIFICATIONSService: Compatible gases and liquids. Wetted Materials: Body: Polycarbonate O-ring: Neoprene & Buna-N. Metal Parts: Stainless Steel (except for optional brass valve). Float: Stainless steel, black glass, aluminum, K monel, tung- sten carbide depending on range. Temperature Limit:130°F (54°C). Pressure Limit: 100 psi (6.9 bar). Accuracy:RMA: 4%, RMB: 3%, RMC: 2% of full scale. Process Connection:RMA: 1/8˝, RMB: 1/4˝, RMC: 1/2˝ female NPT. Weight:RMA: 4 oz (113.4 g), RMB: 13 oz (368.5 g), RMC: 39 oz (1105.6 g). Adjustable pointer flags – Red lined pointer flags provide quick visual reference to a required flow level. Of clear plastic, they snap into place inside bezel and slide to desired level. OPTIONS & ACCESSORIES How To OrderSeries-Range No.-Valve-Option Example:RMA-2-SSV Series RMA with .1-1 SCFH Air Range & Stainless Steel Valve POPULAR RANGES Model RMA RMA-X, Standard RMA RMA-X-BV, RMA with Brass Valve RMA-X-SSV, RMA with Stainless Steel Valve RMA-X-TMV, RMA with Top Mounted Valve Model RMB RMB-X, Standard RMB RMB-X-BV, RMB with Brass Valve RMB-X-SSV, RMB with Stainless Steel Valve Model RMC RMC-X, Standard RMC RMC-X-BV, RMC with Brass Valve RMC-X-SSV, RMA with Stainless Steel Valve RMA-X-APF, Adjustable Pointer Flag for RMA Series RMB-X-BPF, Adjustable Pointer Flag for RMB Series RMC-X-CPF, Adjustable Pointer Flag for RMC Series RKA, Regulator Kit for RMA Series RK-RMB, Regulator Kit for RMB Series *Accuracy ±8% +Accuracy ±5% pg162 7/26/06 1:06 PM Page 1 Bulletin F-43 DWYER INSTRUMENTS, INC. Phone: 219/879-8000 www.dwyer-inst.com P.O. BOX 373 • MICHIGAN CITY, IN 46361, U.S.A. Fax: 219/872-9057 e-mail: info@dwyer-inst.com Specifications - Installation and Operating Instructions Series RM Rate-Master®Flowmeters F A B C J BACK WIDTH K D E G H IFULL OPEN L Dwyer Series RM Rate-Master®Flowmeters are furnished in three models (see Fig. 2), each available in a broad array of flow ranges with direct reading scales for air, gas or water. Installation, operation and main- tenance are very simple. Only a few common-sense precautions must be observed to assure long, trouble-free service. CAUTION: Dwyer Rate-Master®Flowmeters are designed to provide sat- isfactory long-term service when used with air, water or other compatible media. Refer to factory for information on questionable gases or liquids. Avoid solutions of acids, bases or salts having a pH below 5.0 or above 8.5. Caustic solutions, antifreeze (ethylene glycol) and aromatic solvents should definitely not be used. Calibration Each Rate-Master®Flowmeter is calibrated at the factory. If at any time during the meter’s life, you wish to re-check its calibration, do so only with devices of certified accuracy. DO NOT attempt to check a Rate-Master® Flowmeter with a similar flowmeter, as seemingly unimportant variations in piping and back pressure may cause noticeable differences in the indicat- ed reading. If in doubt, return your Dwyer Rate-Master®Flowmeter to the factory. Its calibration will be checked for you at no charge. Before pro- ceeding with installation, check to be sure you have the Rate-Master model and flow range you require. LOCATION: Temperature, Pressure, Atmosphere and Vibration: Dwyer Rate-Master®Flowmeters are exceptionally tough and strong. They are designed for use at pressures up to 100 psi (6.89 bar) and tempera- tures up to 130°F (54°C). DO NOT EXCEED THESE LIMITS! The installation should not be exposed to strong chlorine atmospheres or solvents such as benzene, acetone, carbon tetrachloride, etc. The mounting panel should be free of excessive vibration, as it may prevent the unit from operating properly. A B C D E F G H I (OPEN) J K L 4 -9/16 (11.59) 3 (7.62) 1/8 NPT CONN. 1-5/8 (3.17) 10 - 32 Thds. 3/8 (.95) 1-1/16 (2.60) 1-3/16 (2.73) 3/4 (1.91) 1 (2.54) 1-3/8 (3.49) 3/4 (1.91) 4-13/16 (12.22) 1 (2.54) 8-1/2 (21.59) 6-7/16 (16.35) 1/4 NPT CONN. 3-15/16 (8.56) 1/4 - 20 Thds. 5/8 (1.59) 1-7/8 (3.42) 1-3/4 (3.29) 1 (2.54) 1-7/16 (2.98) 1-13/16 (4.60) 1-1/4 (3.18) 8-3/4 (22.23) 1-1/2 (3.81) Dimensions in Inches (Centimeters) 15 -1/8 (38.42) 12 -1/4 (31.12) 1/2 NPT CONN. 8-3/4 (10.72) 10 - 32 Thds. 1 (2.54) 2-3/4 (5.83) 2-1/4 (5.33) 1-7/16 (2.98) 1-31/32 (3.51) 2-1/2 (6.35) 2 (5.08) 15-3/8 (39.05) 2-1/4 (5.72) Inlet Piping Run:It is good practice to approach the flowmeter inlet with as few elbows and restrictions as possible. In every case, the inlet piping should be at least as large as the connection to the flowmeter; i.e.,1/8″ Iron Pipe Size for RMA models 1/4″IPS for RMB models,1/2″IPS for RMC models. Length of inlet piping makes little difference for normal pressure- fed flowmeters. For flowmeters on vacuum air service, the inlet piping should be as short and open as possible. This will allow operation near atmospheric pressure and thereby insure the accuracy of the device. (Note:for vacuum air ser- vice, the flow control valve, if any, should be on the discharge side of the flowmeter. Either the TMV unit or a separate in-line valve may be applied.). Discharge Piping:As on the inlet, discharge piping should be at least as large as the flowmeter connection. Also, for pressure-fed flowmeters on air or gas service, the discharge piping should be as short and open as possible. This will allow operation of the flow tube at near atmospheric pressure and insure the accuracy of the device. This is of less importance on water or liquid flowmeters, as the flowing medium is generally incom- pressible and moderate back pressure will not affect the accuracy of the instrument as calibrated. POSITIONING AND MOUNTING All Rate-Master®Flowmeters must be mounted in a vertical position with inlet connection at the bottom rear and outlet at the top rear. Bezel or Through-Panel Mounting:Make panel cutout using appropri- ate dimensions from Fig. 2. Flowmeter must fit into panel freely without forcing or squeezing. Insert the flowmeter from the front of the panel and install the mounting clamps from the rear. Insert and tighten the clamp bolts in the locations shown in Fig. 3. Do not exceed 5 in./lbs. Make con- nections to inlet and outlet ports using small amount of RTV sealant or Teflon®thread tape to avoid leakage. Avoid excess torque, which may damage the flowmeter body. PANEL CUTOUT FOR FLUSH MOUNTING 4-5/8 (11.75) 7/8 (2.22) 7/16 (1.11) 1/4 (0.64) 8-9/16 (21.75) 1-5/16 (3.33) 5/8 (1.59) 9/32 (0.71) 15 -3/16 (38.58) 2-1/16 (5.24) 15/16 (2.38) 13/32 (1.03) HIGH WIDE PIPE BOLT Model RMA Model RMB Model RMC Fig. 1 Fig. 2 PANEL HOLE SIZES FOR SURFACE MOUNTING Bulletin F-43 9/14/05 9:01 AM Page 1 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7Fig. 5B Fig. 6B Surface Mounting:Drill appropriate holes in panel, using the dimensions shown in Fig. 2. Hold the flowmeter in position in front of the panel and install the clamp bolts from the rear. (The mounting clamps may be used as washers, if desired, by installing them backwards or straightening them out.) Pipe up inlet and discharge following the directions in the previous sections. Surface Mounting on Piping Only:An alternate method of surface mounting, omitting the clamp bolts and supporting the flowmeter solely on the connecting piping, is possible. For this method, extra-long or straight pipe threads should be used so that nuts may be run onto the pipe and later tightened against the back of the panel to retain the unit in proper position. Use appropriate hole layout in formation from Fig. 2, but omit the small holes. Surface Mounting on Piping Only Without Panel:For a temporary or laboratory type installation, the panel may be omitted altogether and the flowmeter installed directly in rigid piping. Its light weight permits this with- out difficulty. OPERATION To start system, open valve slowly to avoid possible damage. Control valves on BV and SSV models are turned clockwise to reduce flow, counter-clockwise to increase flow. A nylon insert is provided in the thread- ed section of the valve stem to give a firm touch to valve and to prevent change of setting due to vibration. The performance of low range units used in air or gas applications may be affected by static electricity. Excessive static charge may cause the ball float to behave erratically or provide a false reading. To ensure the proper function of the unit, the application should be designed to minimize or dis- pel static electricity. The standard technique for reading a Variable Area Flowmeter is to locate the highest point of greatest diameter on the float, and then align that with the theoretical center of the scale graduation. In the event that the float is not aligned with a grad, an extrapolation of the float location must be made by the operator as to its location between the two closest grads. The fol- lowing are some sample floats shown with reference to the proper location to read the float. Variable Area Flowmeters used for gases are typically labeled with the pre- fix “S” or “N”, which represents “Standard” for English units or “Normal” for metric units. Use of this prefix designates that the flowmeter is calibrated to operate at a specific set of conditions, and deviation from those stan- dard conditions will require correction for the calibration to be valid. In prac- tice, the reading taken from the flowmeter scale must be corrected back to standard conditions to be used with the scale units. The correct location to measure the actual pressure and temperature is at the exit of the flowme- ter, except when using the Top Mounted Valve under vacuum applications, where they should be measured at the flowmeter inlet. The equation to cor- rect for nonstandard operating conditions is as follows: Q2 = Q1 x P1 x T2 P2 x T1 Where: Q1 = Actual or Observed Flowmeter Reading Q2 = Standard Flow Corrected for Pressure and Temperature P1 = Actual Pressure (14.7 psia + Gage Pressure) P2 = Standard Pressure (14.7 psia, which is 0 psig) T1 = Actual Temperature (460 R + Temp °F) T2 = Standard Temperature (530 R, which is 70°F) Example: A flowmeter with a scale of 10-100 SCFH Air. The float is sitting at the 60 grad on the flowmeter scale. Actual Pressure is measured at the exit of the meter as 5 psig. Actual Temperature is measured at the exit of the meter as 85°F. Q2 = 60.0 x (14.7 + 5) x 530 14.7 x (460 + 85) Q2 = 68.5 SCFH Air CAUTION: Do not completely unscrew valve stem unless the flowmeter is unpressurized and drained of any liquid. Removal while in service will allow gas or liquid to flow out the front of the valve body and could result in seri- ous personal injury. For applications involving high pressure and/or toxic gases or fluids, special non-removable valves are available on special order. Please contact factory for details. MAINTENANCE The only maintenance normally required is occasional cleaning to assure reliable operation and good float visibility. Disassembly:The flowmeter can be disassembled for cleaning simply as follows: 1. Remove valve knob from RMB or RMC -BV or -SSV units by pulling the knob forward. It is retained by spring pressure on the stem half-shaft so that a gentle pull will remove it. On RMA-BV or -SSV models, turn the valve knob counter-clockwise until the threads are disengaged. Then withdraw the stem from the valve by gently pulling on the knob. 2. Remove the four mounting bracket screws located in the sides of the flowmeter. See Fig. 3. Pull the flowmeter body gently forward away from the back plate to avoid undue strain on the body. Leave the piping con- nections intact. There is no need to disturb them. See Fig. 4. 3. Threaded body style flowmeters - Remove the slip cap with a push on a screwdriver as shown in Fig. 5. Remove the plug ball stop as shown in Fig. 6 using allen wrench sizes as follows: Model RMA - 1/4″, Model RMB - 1/2″and Model RMC - 3/4″Threadless body style flowmeters - Release the plastic retaining clip with a screw driver (Figure 5B), it will unclip from the valve body (TMV Option) or the plug ball stop, slide the clip back until the valve body or ball stop can be removed. The clip will remain in the body for convenience. Using a screwdriver gently lift up on the plug in the groove as shown in Figure 6B until the o-ring seal is released and remove the plug. For the TMV option gently pull up on the valve knob to release the valve body seals and remove the valve. 4. Take out the ball or float by inverting the body and allowing the float to fall into your hand, as shown in Fig. 7. (Note: It is best to cover the dis- charge port to avoid losing the float through that opening.) Cleaning:The flow tube and flowmeter body can best be cleaned with a little pure soap and water. Use of a bottle brush or other soft brush will aid the cleaning. Avoid benzene, acetone, carbon tetrachloride, alkaline deter- gents, caustic soda, liquid soaps (which may contain chlorinated solvents), etc. Also, avoid prolonged immersion, which may harm or loosen the scale. Reassembly:Simply reverse steps 1 through 4 and place the flowmeter back in service. A little stopcock grease or petroleum jelly on the “O” rings will help maintain a good seal as well as facilitate assembly. No other spe- cial care is required. MOUNTING BRACKET SCREW 4 REQUIRED DWYER INSTRUMENTS, INC. Phone: 219/879-8000 www.dwyer-inst.com P.O. BOX 373 • MICHIGAN CITY, IN 46361, U.S.A. Fax: 219/872-9057 e-mail: info@dwyer-inst.com ©Copyright 2005 Dwyer Instruments, Inc. Printed in U.S.A. 9/05 FR# 56-440197-00 Rev. 16 Teflon®is a registered Trademark of E.I. DuPont Company Bulletin F-43 9/14/05 9:01 AM Page 2