Multiple Tube - Teflon PTFE-Glass Flowmeters

Transcription

1 Multiple Tube - Teflon PTFE-Glass Flowmeters xt Model xt Multiple Tube Teflon PTFE-Glass Flowmeters combine the convenience of multiple tube meters with the unique design features of single tube Teflon PTFE-Glass Flowmeters.These meters are available with the same interchangeable 65mm or 150mm glass flowtubes used in single tube designs and are ideal for applications where several streams of corrosive gases or liquids are to be metered in individual channels or as a controlled mixer in manifolded models. Available with or without built-in Teflon needle valves. Leak Integrity Flowmeters are individually tested on a Mass Spectrometer Leak Detector and certified to a -7 leak integrity rating of at least 1 X 10 sccs of Helium. Design Features * Constructed of inert materials: borosilicate Glass, Teflon (PTFE and PCTFE). * Chemical inert wetted parts within mechanically rigid frame. * Rib-guided or fluted metering tubes facilitate: stable, accurate readings. TM * OPTIGRAD scales minimize parallex and eye fatigue. * Simple means of panel mounting. Panel mounting is convertible to bench mounting through use of an optional acrylic tripod base with spirit leveler (ordered as a seperate item). * Interchangeability of flowtubes and floats. Assorted flowtubes may be used in conjunction with a single mounting frame, an apparent benefit in many laboratory applications. * Conveniently overlapping flow ranges available in both standard millimeter and direct reading scales (see Tables 4, 5, 6, 7 and 8). F L OW METERS F L OW C O N T RO L S Four Tube Teflon meter shown with CVT TM valves

2 Built-in Valves Flowmeters are supplied with or without built-in needle valves. When meters with valves are ordered the valve cartridges are installed at the inlet. For vacuum service it is recommended that meters are ordered with valves at the outlet. CV cartridges or High Resolution needle valves are offered. Specifications s: Wetted Parts: Scales: Accuracy: Max Operating Pressure: Max Operating Temperature: Leak Integrity: 65 or 150mm scale types. Glass (black) or Sapphire (red) suffixes G or S in flowtube numbers Glass (flowtubes) and Teflon PTFE end fittings. 65mm, 150mm or direct reading. ±2% FS (±5% FS for direct reading scales). 100 psig/6.7 bars 150 F/65 C Individually pressure and leak tested and certified to a rating of 1 x 10 sccs Helium. Materials of Construction s: Heavy walled borosicilicate glass, sapphire or glass floats. Fittings in contact with Fluids: Virgin PTFE Teflon PCTFE. Side Plates: Aluminum, black anodized. Front Shield and Back Plate: 1/8 thick clear polycarbonate and white acrylics O-rings: PTFE Teflon Connections: 1/8 NPT female inlet and outlet connections. Optional glass hose or compression fittings. The following flow patterns are available: xt * Glass Sapphire floats are recommended. Table 17 - xt Flowmeter Options. Model End Fitting Valve Flow Number Options Options Tubes 2T53 1/8 FNPT no valve 2 2T53T 1/4 PTFE Comp. no valve 2 2T54 1/8 FNPT CV Cartridge 2 2T54T 1/4 PTFE Comp. CV Cartridge 2 2T51 1/8 FNPT High Resolution 2 2T51T 1/4 PTFE Comp. High Resolution 2 3T53 1/8 FNPT no valve 3 3T53T 1/4 PTFE Comp. no valve 3 3T54 1/8 FNPT CV Cartridge 3 3T54T 1/4 PTFE Comp. Cv Cartridge 3 3T51 1/8 FNPT High Resolution 3 3T51T 1/4 PTFE Comp. High Resolution 3 4T53 1/8 FNPT no valve 4 4T53T 1/4 PTFE Comp. no valve 4 4T54 1/8 FNPT CV Cartridge 4 4T54T 1/4 PTFE Comp. CV Cartridge 4 4T51 1/8 FNPT High Resolution 4 4T51T 1/4 PTFE Comp. High Resolution 4 When ordering please specify: 1. Model options from Tables 15 or 17. Optionally add MT (manifolded at outlet) or MB (manifolded at inlet) after selected model number. 2. Add size of flowtube after model number, i.e. /1 (150mm) or /6 (65mm). 3. Add flowtube or flowtubes (for each channel) from Tables 4, 5, 6, 7 and 8 to numbers. Example: 4T54MT/ G i.e. four tube 150mm model with four G flowtubes, manifolded at outlet with CV cartridge valve. 4. Gases or liquids to be metered. 5. Pressure and temperature of metered fluids.

3 How To Order P xp T xt S G Select the desired flowmeters style, including the choice of end fitting materials and valve options from appropriate catalog pages. Flowmeters are shipped with optional built-in valves installed at the inlets (bottom blocks), unless otherwise instructed. For vacuum service it is recommended that the valves should be positioned at the outlets of meters. Gas proportioners are designed with valves in the upper blocks, downstream from individual flowtubes for component gases. In manifolded multiple tube meters, valves are in the block opposite from the manifolded one (i.e. if manifolding is at the inlet, valves are in the outlet block, and vice versa). Frame Typical 150 mm Frame and Assembly Select flowtubes from Tables 4, 5, 6, 7 or 8. For nonstandard conditions and fluids follow the sizing procedures outlined on page 7. If direct reading scales are desired, Table 8 (page 11) represents typical air and water direct reading flowtubes, consult the company for a complete listing of available direct reading scales. When ordering flowtube subassemblies only, indicate the flowtube numbers including the float suffix. When ordering complete flowmeters it is important to specify frames, flowtube numbers and floats as shown in example below. Two floats may be installed in a flowtube. Assembly Flowmeter Product Code: / Size Code: Make Selection From Catalog Material Code of Fluid Contact Fittings: Black Anodized Aluminum Chrome Plated Brass 316 Stainless Steel Teflon PTFE Valve Option Code: No Valve High Precision TM Metering Valve (MFV ) TM Needle Valve (CV ) Size Code: 150 mm 65mm Options: Select From Tables 4, 5, 6, 7 and 8 or list of Direct Reading Scales Scale Code: Select From Tables 4, 5, 6, 7 and 8 list of Direct Reading Scales Float Code: Glass (black) Sappire (red) 316 Stainless Steel Carboloy (tungsten carbide) Tantalum G S ST C T Example: P 0 4 / G Teflon - Reg. trademark of DuPont Carboloy - Reg. trademark of General Electric Co.

4 Meter Sizing Flow capacity tables 4, 5, 6 and 7 are based on calibrations at standard conditions, meaning psia (1 atm) pressure and 70 F (21.1 C). Tables list maximum flow rates of flowtubes. The usable range of meters is at least 10:1, often more. Thus, as a rule of thumb, to estimate the minimum metering limit divide the flow rates listed, by ten. For gases or liquids with fluid properties not greatly different from the calibration media, tables apply directly, when working pressure and temperature are also approximately standard. Where the above conditions do not apply the maximum flow rates of the metered fluids are converted to equivalent standard flow rates of air or water. To do this calculate K as shown in charts, multiply the maximum flow rate with this factor, and select the appropriate flowtube size from the Flow Capacity tables 4, 5, 6 and 7. Calculation vs. Calibration It is very important that the correction factors as calculated from the accompanying equations are used for sizing only. These relationships are greatly simplified and will not provide precise predictable flow corrections. It is always best practice to calibrate meters for non-standard conditions on site, by using reliable means of calibration. In case of liquid flows at each major point along the scale, sample volumes are collected in a buret of a volumetric flask during measured time intervals. Volumes are interpolated to a unit of time such as for example [ml/min] or [cu. ft/hr] etc. A table or a graph is then constructed to establish a complete set of calibration data. In case of gas flows, calibration data can be similarly developed, except that collection of sample volumes is accomplished by means of gas sampling devices, the simplest of which is a soap bubble meter. Table 1 - Float Densities Material Density [g/ml] glass 2.53 sapphire 3.98 stainless steel 8.04 Carboloy tantalum Gas Flow Q air =K gas X Q gas K gas = Where: G x T act T o x P o P act Q air = equiv.air flow capacity at Standard Conditions (STP) Q gas = maximum flow of metered gas G = specific gravity of metered gas (from Table 3) T act = absolute tempure at flow conditions, deg R or deg K T o = absolute temperature at Standard Conditions (STP) deg R (530) or deg K (294) P act = pressure at flow conditions, psia P o = pressure at Standard Conditions (STP), (14.7 psia) Liquid Flow Q water =K liq X Q liq K liq = Where: (d F - d W ) (d F - d L ) x d L d W Q water = equivalent water flow capacity at Standard Conditions (STP) Q liq = maximum flow of metered liquid d F = density of float selected, (see table 2), (g/ml) d L = density of metered liquid, (g/ml) d W = density of water at Standard Conditions (STP) (1.0 g/ml) Table 2 - Conversion Factors Multiply By To Obtain atm lbs/sq. in atm kg/sq. cm lbs/sq. in kg/sq. cm ml/min liters/min ml/min X 10 cu. ft/min ml/min x 10 gal/hr cu. ft/hr 472 ml/min gal/min 3785 ml/min g/ml lbs/cu. ft g/ml lbs/cu. in Table 3 - Density, Viscosity and Specific Gravity of Gases Gas Density Viscosity Specific Gravity [g/ml] [centipols] G[air=1.0] acetylene air ammonia argon butane carbon dioxide carbon monoxide chlorine ethane ethylene helium hydrogen hydrogen chloride methane nitrogen nitrous oxide oxygen propane sulfur dioxide

5 Table of Standard Flow Capacities Table 5-65mm s (See Table 8 for Gas Flow Capacities) Maximum Flow Rate Number Air Water [sml/min] [scfh] [ml/min] [gph] G Table 4-150mm s S (See Table 7 for Gas Flow Capacities) ST Maximum Flow Rate C Number Air Water T [sml/min] [scfh] [ml/min] [gph] G G S S ST ST C C T ST G G S S ST ST C C T T G G S S ST ST C C T T G G S S ST ST C C T T G G S S ST ST C C T G G S S ST ST C C T G ST G G S S ST ST C C T T G G S S ST ST C C T T G G S S ST ST C C T T * Suffix refers to float materials; G = Black Glass, S = Sapphire (red), ST = 316 Stainless Steel, C = Carboloy, T = Tantalum

6 For direct reading (engineering units) scale flowtubes contact Muis Controls. Flow capacities shown in Tables 4, 5, 6 and 7 are based air or water at STP conditions see paragraph on o on calibrations at standard (STP) conditions (70 F METER SIZING on page 4. o /21.1 C and 14.7psia / 1 atm abs). For fluids other than Table 6-150mm flowtubes, gas flow capacities of routine gases Number Maximum Flow Rate Argon Carbon Dioxide Helium Hydrogen Nitrogen Oxygen [sml/min] [scfh] [sml/min] [scfh] [sml/min] [scfh] [sml/min] [scfh] [sml/min] [scfh] [sml/min] [scfh] G S ST C T G S ST C T G S ST C T G S ST C T G S ST C T G S ST C T G S ST C T G S ST C T G S ST C T *Suffix refers to float materials: G = black glass, S = sapphire (red), ST = 316 stainless steel, C = Carboloy, T = tantalum

7 Table of Standard Capacities Table 7-65mm flowtubes, gas flow capacities of routine gases Maximum Flow Rate Number Argon Carbon Dioxide Helium Hydrogen Nitrogen Oxygen [sml/min] [scfh] [sml/min] [scfh] [sml/min] [scfh] [sml/min] [scfh] [sml/min] [scfh] [sml/min] [scfh] G S ST C T G S ST C T G S ST C T G S ST C T G S ST C T G S ST C G S ST C G ST G S ST C T G S ST C T G S ST C T *Suffix refers to float materials: G = black glass, S = sapphire (red), ST = 316 stainless steel, C = Carboloy, T = tantalum

8 Table 8 - Partial List of Direct Reading Scales (Accuracy = ± 5% F.S.) Table of Standard Capacities Air-65mm Maximum Flow Air-150mm Maximum Flow Water 65mm Maximum Flow Water 150mm Maximum Flow G 7 sml/min S 25 sml/min G 0.5 ml/min S 1 ml/min ST 50 sml/min S 50 sml/min ST 6 ml/min C 10 ml/min G 100 sml/min C 100 sml/min ST 60 ml/min ST 20 ml/min C 250 sml/min S 500 sml/min ST 115 ml/min G 50 ml/min C 500 sml/min G 800 sml/min ST 150 ml/min G 60 ml/min G 1 sl/min C 1.25 sl/min G 250 ml/min G 100 ml/min G 5 sl/min G 2.5 sl/min G 500 ml/min C 200 ml/min ST 10 sl/min S 5 sl/min ST 750 ml/min ST 500 ml/min ST 25 sl/min C 10 sl/min S 1.0 L/min ST 1.2 L/min ST 40 sl/min ST 42 sl/min ST 1.5 L/min T 2 L/min Flowmeters with dual-floats have a turndown ratio better than 20:1 KA Aluminum Kit shown Three types of kits are offered: * Model KA Aluminum Flowmeter Kit. * Model KS Stainless Steel Flowmeter Kit. * Model KT Teflon PTFE Flowmeter Kit. F L OW METERS F L OW C O N T RO L S