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EMCO Multi stage depressurizing unit for liquid

SDP-L: EMCO single hole multi stage pressure reducing units are used to prevent critical/high pressure drops in continuous liquid flow pipe
lines

MDP-L:   EMCO multi hole multi stage pressure reducing units are used to prevent critical/high pressure drops in continuous liquid flow pipe lines. Multi hole plates can handle higher pressure drops than single hole plates 

Principle: By reducing the pressure in stages the damaging cavitation is
avoided. This secures long life time of the equipment.
Cavitation occurs during pressure reduction when the pressure in the
Vena Contracta (the bore of the plate) is lower than the vapour
pressure. Cavitation generates noise, erosion and vibrations.
The calculation is based on ISO 5167, and a critical flow factor or
cavitation factor for determining allowed pressure loss across each
stage. Each of the pressure reducing stages are connected and
supplied as a unit.

Construction
Design and calculation standards
ISO 5167, Handbook, R.W. Miller: Flow Measurement Engineering Handbook, etc., ASME
Sizes
DN 15 – 300, 1/2" - 12", larger sizes on request
Pressure rating
PN 16 – 400, 150 - 2500 lbs
Multi stage design
Constant cavitation factor
Orifice plate shape
Square edge concentric
Plate thickness
thickness is calculated to handle the differential pressure
Distance between each stage
2 - 3 times inner pipe diameter
Material, plates
AISI 316 (standard), and other erosion resistance materials on request
Material, spool piece
P235GH (A106 Gr. B or C), 16Mo3 (F1), other materials on request
Mounting style
Between flanges according to ANSI B16.5 or DIN Standards or butt weld ends.
Overall length
Depends on number of stages and pipe size. Each multi stage unit is calculated individually
Documentation
Material certificate acc. to EN 10204-3.1. Noise calculation
Technical Data
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