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The EMCO EM-CONE Cone type Differential Pressure Producer is used as primary element in flow measurement of liquid, gas and steam according to the differential pressure principle using equations similar to equations for orifices and venturis.
The differential pressure is measured with a differential pressure transmitter between the up stream tapping (+ tapping) in the wall of the cone meter and the down stream tapping (- tapping) in the cone for model EMF CT or in the wall for model EMF-WT
The inlet cone has a good flow con ditioning effect especially for small ß values. This effect supports the short straight pipe run requirements.
Larger size M-CONEs are furnished with vanes for 2 reasons:
1. Better flow conditioning effect.
2. Mechanical support of cone.


  • Wide range of applications
  • Space saving
  • Repeatable.
  • Ideal for difficult applications.
  • Suitable for erosive fluids.
  • No risk of clogging. Self cleaning.
  • Suitable for wet gas metering.
  • Fully in compliance to PED 97/23EC.


Design and calculation standardsEN, PED 97/23 EC, ANSI/ASME
SizesDN 50 - 1000 2” – 40”
Pressure ratingPN 10 - 400, 150 - 2500 lbs
MaterialCarbon steel P235GH, P250GH, A105N, A350LF2, A106 Gr. B, AISI 316, 22 Cr. Duplex, 25 Cr. Duplex, 6Mo, 16Mo3 (F1), 13CrM o4-5 (F11) 10CrMo9-10 (F22), other materials on request
Mounting styleWeld ends according to EN 9692-1 or ANSI B16.25.
 Flanges connection according to DIN, ISO or ANSI.
 Hub connection for clamping between hubs (Grayloc).
Pressure taps½”, ¾” NPT ext., ½”, ¾” flanged, others on request
Flange facingFlat or raised face according to DIN 2526 or flat, raised face or ring type joint according to ANSI B 16.5
Beta ratio (d/D)0,4, 0,5, 0,6, 0,7 and 0,85 (0,7 is standard).
  D : inner pipe diameter, d : cone diameter

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Beta Ratio

The definition of β for cone meters is different from orifice plates and venturis where  β = d/D.
The free area for a given M-CONE is the same as for  orifice plates and venturi tubes

Cone meter : β = Sqrt (1-(d^2/D^2)

Tapping arrangements

  • 2 types of tapping arrangements are available.
  • Type EMF-CT:
  • The most common type has the up stream pressure taken from a tapping in the wall of the cone meter and the down stream pressure taken from the down stream side of the cone with an internal line to a tapping in the wall.
  • Type EMF-WT
  • The most universal one has the up stream as well as the down stream pressure taken from tappings in the wall of the cone meter.
  • Whenever there is a risk of trapping air/gas in a liquid flow measurement or liquid/condensate in a gas flow measurement the type EMF-WT should be selected.


DIN Flanges

Tapping selection table.   
Pipe orientation   
FluidHorizontalVertical downVertical up
LiquidCT or WTWTCT or WT
SteamCT or WTCT or WTWT

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Pressure loss comparison

The pressure loss of a differential pressure flow meter depends on the mechanical design of the  element. More specifically the outlet section of the restriction determines the pressure loss.
DP elements with high pressure recovery have low pressure loss and low pressure recovery elements have high pressure loss.
An orifice plate creates turbulence downstream, consequently the pressure recovery is low and therefore the pressure loss is high.
The classical venturi tube has a high pressure recovery due to the long outlet cone creating a steady velocity decrease and pressure increase. Therefore the classical venture tube has a very low pressure
The M-CONE cone meter has an outlet cone with a large angle creating some turbulence but certainly not so much as an orifice plate. The pressure recovery for a cone meter is not as high as a classical venturi tube and therefore the pressure loss is higher for a cone meter than a classical venturi tube.
The cone meters do not require pipe line reduction in order to measure correctly in the full range as the Vortex flow meter. This pipe line reduction causes pressure loss. Therefore the pressure loss of a cone meter is lower than a vortex meter.

Technical Data 
Accuracy+/- 1-2 % (un-calibrated), +/- 0,5 % (calibrated).
Repeatability+/- 0,1 %
Pressure loss40 % of measured differential pressure with beta ratio 0,7
Limits for Reynolds No.Re > 10.000, lower Re. Consult factory
Installation requirementDown to 5 x D up-stream and 2 x D down-stream.


  • Primary shut-off valves
  • Condensing chambers for steam flow measurement.
  • Steam jacket (only type EMF-WT)

Overall Dimensions

DN/InchWeld End150 lbs300 lbs600 lbs900 lbs1500 lbs2500 lbsHub connection
50 / 2”275400400450-500600350
65 / 21⁄2”325450450500-550600350
80 / 3”360500500550650650750460
100 / 4”400550550600700700800500
150 / 6”5707507508009009001100800
200 / 8”650850850900110011001300900
250 / 10”70090090010001200120016001000
300 / 12”7701000100011001250130017001100
350 / 14”80010501050110012501400-1200
400 / 16”80010501050115013001400-1520
450 / 18”82011001150120014501500-1300
500 / 20”91012001300135016001700-1400
600 / 24”119515001500160018001900-1600
700 / 28” 17001800190020002050--
800 / 32” 170019501950----
900 / 36” 170019502000----
1000 / 40” 20002200-----

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Works with:-Differential pressure transmitters:-IDP10; IDP15; IDP25; IDP31; IDP50
And all our Absolute Pressure and Gauge Pressure transmitters, Temperature sensors and mass flow computers.
MultiVariable Transmitters :- IMV25, IMV30 


Download Datasheet Cone type 'EM-Cone' Differential Pressure Flowmeter

Download Manual (Not Available)


If you require further information on this product or would like a quotation, please contact dp-flow on:

sales +44(0)1865 600245