Orifice Plate Assembly
The most widely used differential pressure flow measurement device — a precision-machined plate with concentric, eccentric, or segmental bore installed between orifice flanges with pressure tappings for gas, steam, and liquid service.
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BETFLOW Orifice Plate Assembly (BF-OPA)
The Orifice Plate Assembly is the most widely used differential pressure (DP) flow measurement device, consisting of a precision-machined plate with a concentric, eccentric, or segmental bore, installed between a pair of orifice flanges along with pressure tappings. As fluid passes through the bore, it creates a predictable pressure drop that is measured across the plate to determine flow rate.
Being simple in construction with no moving parts, the orifice plate assembly offers a reliable, low-maintenance, and cost-effective solution for flow measurement in gas, steam, and liquid service, making it the standard choice across the process industry.
Bhavyam offers all orifice plate assemblies under the BETFLOW range of products. Design & engineering is done as per global standards to meet challenging process demands. Manufacturing of all orifice plate assemblies is carried out as per ISO 5167 / ASME MFC-3M / AGA 3 / BS 1042 / ASME B16.5 / ASME B16.36 standards.
Specifications
- Orifice Plate type: Square Edged Concentric Orifice Plate, Eccentric Orifice Plate, Quadrant Edge / Quarter Circle Orifice Plate, Conical Entrance Orifice Plate, Segmental Orifice Plate
- Plate Material: SS316 & SS316L as standard. SS304, SS304L, Hastelloy, Monel, Inconel, Titanium, PTFE, PVC, PP, and others on request
- Plate Thickness: 3.18mm, 6.35mm, 12.7mm as standard, and others on request
- Vent / Drain: vent or drain holes are provided as per process requirement
- Orifice Flange type: as per ASME B16.36, ASME B16.5, ASME B16.47 Series A/B. Flanges as per EN standard are also provided on request
- Flange Material: ASTM A105 & ASTM A182 F316 as standard. ASTM A182 F304, ASTM A182 F11, ASTM A182 F22, PTFE, and others on request
- Pressure Tapping: flange taps, corner taps, pipe taps, radius taps
- Gaskets: CNAF, SS spiral wound with grafoil filler as standard. PTFE, graphite, and others on request
- Stud / Nut: ASTM A193 Gr. B7 / A-194 Gr. 2H as standard, other material on request
- Jack Screw: ASTM A193 Gr. B7 as standard, other material on request
- Testing: PMI, Hydrotest, Dye Penetration Test, Radiography, Flow Calibration, and others on request.
Applications we serve.
- Flow measurement in gas, steam, and clean liquid pipelines
- Custody transfer and fiscal metering in oil and gas
- Boiler feedwater and steam flow measurement
- Chemical and petrochemical process flow monitoring
- Compressor and pump station flow measurement
- Flare gas and vent line flow monitoring
- Water and wastewater treatment flow measurement
- Multi-hole designs for mildly contaminated gas or liquid service
Frequently asked questions.
What is the difference between concentric, eccentric, and segmental orifice plates?
A concentric plate has a centred circular bore and suits clean, single-phase fluids. An eccentric plate has an off-centre bore and is used where small amounts of entrained liquid, gas, or solids need to pass without accumulating. A segmental plate has a segment-shaped opening and is typically used for fluids carrying a higher proportion of suspended solids or a second phase.
How is the orifice bore size determined?
The bore is sized from the fluid type and phase, the flow rate (minimum, normal, maximum), the operating pressure and temperature, the pipe internal diameter, and the desired permanent pressure loss, following the calculation procedure in ISO 5167 or AGA 3. The beta ratio is selected to balance accuracy, pressure loss, and the DP transmitter's range.
What length of straight pipe is required upstream and downstream of an orifice plate?
The required straight length depends on the beta ratio and the type and location of the nearest upstream fitting (elbow, valve, reducer, etc.), as specified in ISO 5167 and AGA 3. Where sufficient straight length is not available, a flow conditioner can be installed to reduce the required length.
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