STANDARD PNEUMATIC ACTUATOR

Product catalog summary

Valve Specification
The M Valve is a miniature air-operated proportional control valve suitable for liquids, gases, or steam, available in 1/4” and 1/2” line sizes. It features a wide range of inner valve trims offering flow control with Cv values from 3.0 to 0.00008. The valve body is made of Stainless Steel 316 S31, with options for Carbon Steel, Monel, Hastelloy, and PVC. The valve plug is made of Stellite 6, and the valve seat is 416 Stainless Steel, with options for Hastelloy, Monel, and Stellite. The control range for trims A-N is 40:1, and for trims P0-P9 is 12:1. The leak rate is less than 1% of max Cv/Kv when closed. The valve can operate under pressures up to 150 Bar and temperatures from -75ºC to 190ºC, with options up to 400ºC using cooling fins.

Actuator Specification
The standard pneumatic actuator requires a 3-15 psi clean dry instrument air input and is suitable for valve trims sized A-N. The actuator housing is made of die-cast aluminum, with nitrile rubber rolling diaphragm/seals, and operates in ambient temperatures from -20ºC to +50ºC. A pneumatic positioner is available for increased positioning accuracy or higher pressure drops, suitable for trims P0-P9 and A-N.

How to Specify
To specify an M Valve, provide details such as line size, connection type, preferred valve materials, fluid type, line pressure and temperature, maximum flow rate, upstream and downstream pressures, valve characteristics (Air-to-Open or Air-to-Close, Linear or Equal % Trim), and any special conditions like particles or bubbles in the fluid.

Choice of Trim Flow Range
The M Valve uses a trim plug and seat combination sized for the required flow rate control. Trim sizing uses the Cv or Kv value, calculated for specific site fluids and conditions. Trims A-N offer a 40:1 control range, while trims P0-P9 offer a 12:1 range. Control characteristics can be linear or equal percentage, with equal percentage trims doubling the original flow for a 15% linear opening.

Trim Sizing Formulae
The document provides formulae for calculating Cv and Kv values for liquids, gases, and steam, applicable to clean, bubble-free liquids with no cavitation or flashing and a minimum Reynolds Number of 100,000.

Catalog excerpts

CONTROL CHARACTERISTIC The normal control characteristics for all trim sizesgives a linear relationship between valve lift and flow rate.For 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. > To properly specify the process conditions andcontrol requirements for an M Valve application, please supply the following information:...

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1/4Քor 1/2proportional control The M Valve is a miniature air operated proportional control valve for use on liquids,gases or steam. Available for 1/4Ԕand 1/2line 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 trims the M Valve is ideal for pilot plant control, representing a scaled down version of larger process control valves.With linear,equal percentage and quick openingcontrol characteristics,the M Valve also has specific application in dosing,sampling and blending...

Open the catalog to page 4