DS1810 TTELEC | Alldatasheet

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AIR OPERATED CONTROL VALVE - THE ‘M’ VALVE The M Valve is a miniature air operated proportional control valve for use on liquids or gases. Av ailable for 1/4” and 1/2” line sizes, a wide range of inner valve trims offer flow control with CV values from 3.0 down to 0.00008. Each valve has a control range of as much as 40:1 and with interchangeable tr ims the M Valve is ideal for pilot plant control, repr esenting a scaled down version of larger process control valves. With linear, equal percentage and quick opening control characteristics, the M Valve also has specific application in dosing, sampling and blending systems. Standard valve material is forged 316 Stainless Steel: alternatives of Hastelloy, Monel, PVC or carbon steel body materials are available with Stellite or other trim materials as required. The standard Air actuator uses a 3-15 psi control input of either Air-to-Open or Air-to-Close. For higher line pressure applications a standard top mounted positioner is recom mended, incorporated into the valve. For high integrity applications, alternative designs of valve seal are available. Extension bonnets or cooling fins are used for cold service or high temperature duty.

FEATURES

/circle61/4” or 1/2” proportional control /circle6Interchangeable trims /circle6CV values 0.00008 to 3.0 /circle6Air operated /circle6Stainless Steel valve and trim standard /circle6Linear or equal percentage control characteristics /circle6Accurate low flow control STANDARD AIR-TO-CLOSE VALVE

Body Stainless Steel 316 S31 (Options :c arbon steel, Monel, Hastelloy, PVC) Trim 1/2”Valves:Sizes A-F:Stainless Steel 1/4”Valves: Sizes F-N: Stainless Steel 1/4”Valves: Sizes P0-P9: Drive Stem: 316 Stainless Valve plug: Stellite 6 Valve seat: 416 Stainless Steel (options: Hastelloy, Monel, Stellite) Cv/Kv Values See tabulation on back page Control Range Trims A-N: 40:1 Trims P0-P9: 12:1 Leak Rate L ess than 1% of max Cv/Kv when closed (the M valve is not an isolating valve) Packing Solid PTFE Standard (Option: Chevron seal) Connections 1/4” or 1/2” NPT female (Options: flanges or weld fittings) Pressure 150 bar max (subject to valve packing) Fluid -75ºC to 190ºC Temperature( Options to 400ºC with cooling fins) Valve Stroke 1/4” valve 11mm 1/2” valve 14mm (V isual position indicator on valve stem) ACTUATOR SPECIFICATION 1. STANDARD PNEUMATIC ACTUATOR Signal Input Director acting 3-15psi clean dry instrument Air Suitable ApplicationsValve trims sized A-N, where pressure drop across valve does not exceed: Trims A-B: 63psi Trim C: 85psi Trims D-E: 140psi Trims F-J: 360psi Trims K-N: 1000psi Positioning AccuracyAffected by pressure drop across valve: maximum offset 5% at DP quoted above Connection Thread 1/4” NPT Variants Air-to-Open or Air-to-Close Housing Die-cast aluminium Rolling Diaphragm/Seals Nitrile rubber Temperature -20ºC to +50ºC ambient 2. PNEUMATIC POSITIONER Type Top mounted positioner built onto standard Air motor Suitable ApplicationsValve Trims P0-P9 Valve Trims A-N, where increased positioning accuracy is required, or where pressure drop across valve exceeds the figures quoted for standard pneumatic actuator Air Supply Max: 100psi/min: 5psi above required valve actuation pressure Signal Input 3-15psi Connection Thread 1/4” NPT Variants Air-to-Open or Air-to-Close Temperature -20ºC to 50ºC ambient AIR-TO-OPEN WITH PNEUMATIC POSITIONER AIR-TO-CLOSE STANDARD ACTUATOR (CUTAWA Y)

To properly specify the process conditions and control requirements for an M Valve application, please supply the following information: /circle6Line size /circle6Connections required /circle6Valve materials preferred /circle6Fluid type (specify density and viscosity if unusual) /circle6Line pressure and temperature /circle6Maximum flowrate and flow control range required /circle6Upstream pressure /circle6Downstream pressure /circle6Valve characteristics - Air-to-Open or Air-to-Close - Linear or Equal % Trim /circle6Special conditions - eg particles or bubbles in fluid CHOICE OF TRIM FLOW RANGE The M Valve body is fitted with a Trim plug and seat combination, matched together and sized to give the required flow rate control. Trim sizing uses the Cv or Kv value, a parameter calculated for the specific site fluids and conditions according to standard formulae, as quoted overleaf. The tabulation presented there shows, for each trim, the Cv/Kv value when the valve is fully open. For Trims A-N, control is available over a 40:1 range, representing flow rates between 2.5% and 100% of maximum. Smaller trims, sizes P0-P9, have a 12:1 control range available. CONTROL CHARACTERISTIC The normal control characteristics for all trim sizes gives a linear relationship between valve lift and flow rate.F or Trim sizes A-J, an alternative characteristic is available: this is the Equal Percentage Trim, where equal increments of valve lift produce constant percentage increments of flow through the range. The graph shows this characteristic, where Equal Percentage trims have double the original flow for a 15% linear opening of the valve. Trim (Plug and Seat) Tapered Plug Valve Seat (Removable) Linear % Flow 100 100 0 0 % Travel Equal Percentage Travel

The tabulation gives the Cv and Kv values for each Trim size, as calculated according to the formulae below: NOTE: Liquid formula applies only to clean, bubble free liquid with no cavitation or flashing and with Reynolds Number 100,000 mi nimum. US UNITS Cv = Q Q= F l o w US GPM G= Specific Gravity (H20=1) ∆P= Pressure Drop, psi Cv = Q Q = Flow, SCFH G= Specific Gravity (Air=1) T= T emperature, ºK P= Inlet Pressure psia ∆P= Pressure Drop psi G

293 P ∆P

Kv = Q Q= F l o w m G= Relative Density (H20=1) ∆P= Pressure Drop bar Kv = Q Q = Flow Nm G= Relative Density (Air=1) T= T emperature ºK P= Inlet Pressure, bar abs ∆P= Pressure Drop, bar G 3.0 2.0 1.25 0.8 0.5 0.32 0.2 0.13 0.08 0.05 0.03 0.02 0.01 0.006 0.003 0.002 0.0013 0.001 0.0006 0.0004 0.00027 0.00018 0.00012 0.00008 Kv MAX 2.6 1.7 1.1 0.7 0.43 0.27 0.17 0.11 0.07 0.04 0.026 0.017 0.0086 0.0052 0.0026 0.0017 0.0011 0.00086 0.00052 0.00034 0.00023 0.00015 0.0001 0.00007 TRIM A B C D E F G H I J K L M N Valve Size A B C 1/4” 54 50 15 1/2” 70 73 25 DIMENSIONS C B 180mm Topworks Air-to-Close 200mm (360mm with positioner) A 150mm Ø 115mm Topworks Air-to-Open 200mm (315mm with positioner) 150mm Ø

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Tel: +44(0)114 244 2521 Fax: +44(0)114 243 4838 email: sales@roxspur.com www.roxspur.com Every effort has been made during the preparation of this document to ensure the accuracy of statements and specifications. Howe ver, we do not accept liability for damage, injury, loss or expense caused by errors or omissions made. We reserve the right to withdraw or amend products or documentation without notice. Head Office: 2 Downgate Drive, Sheffield, S4 8BT, England Tel: +44(0)114 244 2521 Fax: +44(0)114 243 4838 03HWAR0510