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EMCO Wedge Meter, Type EWF

Principle: The EMCOWEDGE type EWF is very suitablte for viscous liquids. The wedge design makes it less sensitive for solid particles and therefore no risk of clogging. 

Bi-directional flow is possible.

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Element ratio (h/D), h = wedge gab, D = inner pipe diameter

Pipelines carrying highly viscous liquids are often heated by steam tracing. EMCOWEDGE can be delivered with steam tracing for lowering the viscosity for better measuring accuracy.

The steam tracing can be delivered in 2 designs: Semi-steam jacket and full steam jacket. The latter is supplied with process flange connection typical 2 pipe sizes larger than the process pipe. The steam jacket is supplied with 2 steam connections and 1 drain connection

Design and calculation standards
ISO 5167-6, EN, PED 97/23 EC, ANSI/ASME and RW Miller
DN 50 600 2” – 24”, larger sizes upon request.
Pressure rating
PN 10 400, 150 2500 lbs
Carbon steel P235GH, P250GH, P265GH, A105N, A106 Gr. B, A350 Gr. LF2, A335 Gr. P5 and P9, AISI 316, Duplex, Super Duplex, 6Mo, heat resisting steels, other materials on request including internal hard facing by cladding.
Material wedge
As pipe material above including optional cladding of hard alloy materials. Solid wedge according to ISO 5167-6.
Mounting style
Flanges connection according to ISO, DIN or ANSI
Pressure taps
DN 25, DN 50 and DN 80, 1”, 2” and 3” or small size tappings : 4 – 10 mm, Standard is 1 set of tappings. Optional 2 or 3 sets of tappings available. Close coupled tappings (studed olet) with reduced tapping volume. Special flanges for chemical seals.
Flange facing
Flat or raised face according to DIN 2526 or flat, raised face or ring type joint according to ANSI B16.5
Element ratio (h/D)
0,2, 0,3, 0,4, 0,5 and 0,6 (β between 0,377 and 0,791) according to ISO 5167-6
Discharge coefficient C
0,77 – 0,09 x β. In accordance with ISO 5167-6 applicable for sizes 50mm ≤ D ≤ 600mm
0,377 ≤ β ≤ 0,791 (0,2 ≤ h/D ≤ 0,6)
Technical Data
+/- 4 % un-calibrated, +/- 0,5 % calibrated. (of discharge coefficient)
+/- 0,2 %
Pressure loss
(1,09 – 0,79 x β) x DP
Limits for Reynolds No
10.000 – 9.000.000
Installation requirement
7 x D up-stream and 6 x D down-stream taken from the end of the disturbance to the centre line of the up-stream tapping and from the centre line of the down-stream tapping to the start of the disturbance according to ISO 5167-6.
shut-off valves
Condensing chamber for steam flow