Multi Hole Compact Orifice

Multi Hole Compact Orifice

The Multi Hole Compact Orifice flow meter measuring most liquids and gases. The meter is a conditioning flow orifice assembly designed to slip between DIN and ANSI flanges, and is designed for compact mounted dp cells. With an installation length of 32mm it can be installed in existing systems simply and easily, and incorporates the dp flow priciple. d/p metering enables easy re-calibration routines for process operators, negating the need for expensive flow metering spares and external flow recalibration services.

Benefits

• Sizes ranging from DN 40 (1½") up to DN 400 (16").
• Designed for limited space installations, flow conditioning effect created by the 5 hole design.
• No moving parts.
• Not sensitive to vibrations.
• Compact design.
• Easy to install.
• High accuracy.

Typical Applications

The Multi Hole Compact Orifice flow meters measure the flow of most liquids and gases within the process industries, including chemical, petrochemical, phamacutical and the power industry. The Multi Hole Compact Orifice is especially designed for installations with limited space due to the flow conditioning effect created by the 4 hole design. It is based on the principle of measuring velocity in the pipe line, therefore the flow measurement is volumetric. The flow meters are based on international standards and private information covering flow calculation, manufacturing tolerances, accuracy and installation requirements. This new type of 'fundamental' technology increases the number of potential successful applications for DP flow meters in world.

The flow meter features are:

• VERY short straight pipe run requirement
• Standardised product based on well proven technology.
• Compact design.
• Simple construction.
• Free choice for horizontal or vertical pipe run.
• Standardised construction means low inventory.
• No moving parts.
• Not sensitive to vibrations.
• The electronics delivers output signal linear to flow.
• Digital indicator for local flow reading.
• High accuracy.
• Wide rangeability.
• Easy to install.
• Easy to re-calibrate.

Construction

The standard for primary elements ISO 5167-1 describes different types of flow conditioners (flow straighteners) avaiable. These elements are inserted up stream the flow meter to improve the flow profile.
The 4 hole flow meter combines a traditional single hole orifice plate with a flow conditioner. This reduces the straight pipe run up stream of the flow meter, which can be  reduced from 20 times inner pipe diameter to 2 times inner pipe diameter.

Model Multi Hole Compact Orifice

The Multi Hole Compact Orifice flow meter model consists of a primary element based on the differential pressure principle with an integrated 3 valve manifold valve and an electronic differential pressure transmitter with digital signal processing.
The flow meter is mounted between flanges in sizes from DN 40 (11⁄2") to DN 400 (16") in pressure ratings up to PN 40 (300 lbs).

Accessories

Remote Mounting Kits are available if remote mounting of electronics is required in case of difficulty accessing the pipeline or if there are elevated process temperatures.
The customer has to provide the stainless steel instrument tube Ø 12 x 1 mm between flow meter and electronics. Remote electronic indicator with LCD is available for local flow indication and if required check/change of flow rate (differential pressure).

Principle of measurement

The Multi Hole Compact Orifice is a velocity flow meter. A restriction in a pipe line changes the value of respective momentum energy, in terms of static and dynamic pressure. Based on the laws of energy balance developed by Bernoulli, the sum of the energies remain constant. Increasing the velocity in the pipe line, decreases the pressure in the restriction. The pressure differential between the inlet pressure and the pressure in the restriction is measured and expressed as flow velocity. When the physical values of the fluid are known and the inner pipe diameter is established the electronics calculates the flow rate. The flow rate is expressed in an analogue signal 4 - 20 mA signal or via digital communication.

Technical data

• Sizes : DN 40 - DN 400, 11⁄2" - 16", larger sizes on request
• Pressure rating : up to PN 40, 300 lbs, higher pressure ratings on request
• Temperature : Process : -50 - +150°C,
• higher temperature with Remote Mounting Kit
• Mounting style : Between flanges according to DIN or ANSI standards
• Flange facing : flat face (standard), raised face, DIN 2512 N, DIN 2513 R
• Overall length : 32 mm
• >Material : Stainless steel AISI 316, others on request
• Design and calculation standards : ISO 5167, ASME MFC-3M.
• Vent or drain hole : On request
• β (d/D) : 0,5 and 0,6; other β on request.
• Accuracy : +/- 1 %
• Rangeability : 8:1
• >Repeatability : better than 0,1 %
• Pressure loss : typical 150 mbar for liquid flow, and 50 mbar for gas flow (values are given at full flow)
• Reynolds No : Re > 5000
• Allowable differential pressure : max 2,5 bar
• Output signal : analogue 4 - 20 mA or Digital communication via protocol, HART, PROFIBUS, Fieldbus Foundation or others.
• Local indicator (option): LCD showing flowing units or %
• Power supply : 14 - 36 Vdc, typical 24 Vdc.
• Max load (24 Vdc) : 700 Ohm
• Enclosure : IP 67
• Ex protection : intrinsically safe EEx ia IIC T6,Explosion proof EEx d IIC T6
• Temperature : Ambient : -40 - +80°C

Sizes

DIN flanges

ANSI Flanges

Overall Dimensions 

Installation requirements

The Multi Hole Compact Orifice flow meter can be mounted in a horizontal or vertical pipe. For liquid flow in a horizontal pipe the electronics shall be mounted below the pipe. For gas flow in a horizontal pipe the electronics shall be mounted above the pipe. High accuracy of measurement is achievable even with short straight pipe runs up-stream from the flow meter. The required straight pipe run is only 2 x inner pipe diameter and 2 x downstream to maintain an accuracy of 2%. If mass flow required due to changing process conditions ask for the mass flow meter data sheet. Saturated and superheated steam is covered by the Multi Hole Compact Orifice flow meters

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

Supplied by DP-Flow