Multi-Hole Orifice Plate Flow Meter
Lower noise, shorter straight-pipe runs.
DN50 to DN1200 · ±0.5 % of flow · ISO 5167
PN0.6 to PN42 MPa · −200 to +800 °C
Beta 0.20 to 0.75 · corner / D & D/2 / flange taps
- Multi-hole disc splits one jet into several smaller jets; lower aerodynamic noise on noise-sensitive lines
- Velocity profile recovers faster than a single-hole orifice; shorter upstream run inside the ISO 5167 table
- Transmitter-flexible: pair with buyer-supplied Rosemount 3051, Yokogawa EJA, Honeywell ST3000, or order the integrated build
Multi-hole disc · corner / D & D/2 / flange taps · ISO 5167
Several smaller jets → lower noise · faster velocity-profile recovery
Multi-hole orifice plate flow meters are designed to measure clean liquid, gas, and steam through a perforated disc primary element that follows ISO 5167 / GB/T 2624 conventions. The multi-hole pattern splits the single jet of a standard orifice into several smaller jets at lower velocity, which lowers downstream aerodynamic and hydrodynamic noise and conditions the velocity profile faster than a single bore. DN50 to DN1200, PN0.6 to PN42 MPa, −200 to +800 °C, ±0.5 % of flow. Pair with a buyer-supplied Rosemount 3051, Yokogawa EJA, or Honeywell ST3000 DP transmitter, or order the integrated build with a factory-mounted ProFlow DP transmitter on a 3-valve manifold. Ships 5–7 business days.
Benefits
- Lower jet noise: several smaller jets in place of one large jet; useful on residential-adjacent HVAC, lab, and food-process headers where line noise is a complaint.
- Shorter upstream run inside the ISO 5167 table: the multi-hole pattern conditions the velocity profile faster, so 22 D to 30 D upstream typically meets spec where a single-hole orifice would need the full 30 D to 50 D.
- DN50 to DN1200 pipe range with corner taps, D and D/2 taps, or flange taps per ISO 5167-2; flange material matched to the pipe schedule.
- PN0.6 to PN42 MPa pressure rating across −200 to +800 °C medium temperature; covers cryogenic LN2/LOX/LH2 through superheated steam.
- Wetted material options: 304 / 316 / 316L / 321 stainless steel standard; 12CrMo and Cr5Mo chrome-moly for hot steam; Hastelloy, Monel, and Titanium by quote for chemical service.
- Transmitter-flexible: order element-only and pair with a buyer-supplied Rosemount 3051 / Yokogawa EJA / Honeywell ST3000, or order the integrated build with a factory ProFlow DP transmitter at 4-20 mA, HART, or RS-485 Modbus.
- Lead time 5–7 business days from the factory.
Configure your build.
Pick pipe DN, pressure rating, wetted material, tap geometry, and DP transmitter option. The configurator returns the PF-LG-PH model code and a ballpark unit price; engineering replies with a sized β and quote within one business day.
Your Configuration
✓ ISO 5167 / GB/T 2624 wet-flow cal cert
✓ Reply within 4 business hours
Typical applications
Four applications where the multi-hole disc earns its place over a single-hole orifice.
Residential-adjacent HVAC headers
Chilled-water and condenser risers in offices, hospitals, and hotels where line noise carries to occupied spaces. Several smaller jets drop the broadband noise the single jet of a standard orifice creates.
Lab utility and process headers
Compressed-air, instrument-air, and cooling-water runs in research labs and pilot lines where short straight-pipe sections and noise complaints both matter. The multi-hole disc handles both at once.
Food and beverage process water
Process-water and CIP supply on food-grade plants where line noise reaches packaging floors. The element ships in 316L stainless; sanitary CIP/SIP geometry is not in scope; route sanitary service to Coriolis or EMF.
High-pressure steam and gas let-down
Saturated and superheated steam headers and high-pressure natural-gas let-down stations where the disc both measures flow and conditions the jet profile after the pressure-reducing valve. PN42 MPa rating covers main-steam and trunkline service.
Specifications
| Measurement principle | Differential-pressure primary element; multi-hole disc creates a ΔP that scales with the square of volumetric flow per ISO 5167 / Bernoulli; DP transmitter applies square-root extraction to output flow |
|---|---|
| Accuracy | ±0.5 % of flow per ISO 5167 wet-flow cal on the factory loop |
| Repeatability | ±0.1 % typical for an ISO 5167 conformant install |
| Reference standard | ISO 5167 / GB/T 2624 (Chinese national adoption of ISO 5167 series) |
| Pipe size | DN50 to DN1200 |
| Pressure rating | PN0.6 / 1.0 / 1.6 / 2.5 / 4.0 / 6.4 / 10 / 16 / 25 / 42 MPa |
| Medium temperature | −200 to +800 °C |
| Beta ratio | 0.20 to 0.75; sized by quote against flowing P, T, and ΔP budget |
| Tap geometry | Corner taps / D and D/2 taps / Flange taps (1″ from each face), per ISO 5167-2 |
| Wetted material | 304 / 316 / 316L / 321 stainless steel standard; 12CrMo and Cr5Mo chrome-moly for hot steam service; Hastelloy, Monel, Titanium by quote |
| Flange standard | HG/T 20592 PN rating standard; ANSI 150 / 300 / 600 / 900 / 1500 lb by order |
| Applicable media | Clean liquid (water, glycol, refined hydrocarbon, condensate, cryogenic LN2/LOX/LH2/LAr), clean gas (air, N2, O2, CO2, natural gas, hydrogen, instrument air), saturated and superheated steam; single-phase, full-pipe |
| Turndown | 1:3 with standard 4-20 mA DP transmitter; 1:7 to 1:10 with HART smart transmitter |
| DP transmitter option | None (buyer-supplied) / ProFlow 4-20 mA HART (separately mounted within 3 m) / integrated build (factory-mounted with 3-valve manifold) |
| Output signal (integrated build) | 4-20 mA loop / HART / RS-485 Modbus RTU |
| Hazardous-area certification (integrated build) | Ex d IIC T6 Gb on the DP transmitter housing; the mechanical primary element is passive and needs no Ex cert |
| Ingress protection (integrated build) | IP65 standard; IP66/67 by special order |
| Calibration certificate | ISO 5167 / GB/T 2624 wet-flow cal on the factory loop; ISO 9001 quality cert; mill cert traceable to heat number on the wetted-metal grade |
| Lead time | 5–7 business days from factory |
Installation
Five field rules for an ISO 5167 conformant install and a stable DP signal.
- Upstream straight pipe per the ISO 5167 table The LG series table applies: for a single 90° elbow at β = 0.5 the upstream run is 22 D and downstream 5 D; at β = 0.75 the upstream run is 44 D; two elbows in different planes call for 50 D upstream; a reducer is 16 D; a regulator or control valve is 30 D or use a flow conditioner. The multi-hole disc lets the velocity profile recover faster, so 22 D to 30 D upstream typically meets spec on the easier disturbance cases.
- Horizontal orientation preferred; flow direction stamped on the disc body Horizontal is the standard for liquid and gas. For steam and condensable gas, mount horizontally with impulse lines sloped downward to the transmitter so condensate drains back. Vertical mount is permitted with the flow direction marked; do not flip the disc; the published β and discharge coefficient are direction-specific.
- Pick tap geometry to match the install Corner taps are flush to the disc carrier ring; compact, lowest install effort. D and D/2 taps sit one pipe diameter upstream and half a diameter downstream; classical convention, slightly tighter accuracy on small bore. Flange taps sit 25.4 mm (1 inch) from each face of the plate; the most common choice for DN50 to DN600 service because the flange already carries the bosses.
- Impulse lines sloped 1:10 toward the transmitter for liquid, toward the primary for gas Use 8 to 12 mm OD stainless tubing with a 3-valve or 5-valve manifold at the transmitter. Keep total impulse length under 5 m to minimize lag. Add steam-tracing or electric heat-tracing on cold-ambient runs (below 0 °C ambient) with liquid or condensable gas in the lines; the build does not ship a heat-trace option; buyer responsibility.
- Zero the DP transmitter after install with the line pressurized and flow stopped Open the equalizing valve at the manifold (cell sees zero ΔP under static pressure), zero the transmitter against the sized URL, then close the equalizing valve and open the isolation valves to put the cell back in service. Record the baseline offset; routine re-zero every 6 to 12 months catches drift before it shows up on the totalized reading.
Frequently asked questions
Need help sizing the multi-hole orifice plate build?
Send pipe DN, schedule, flowing P and T, fluid, and min/normal/max flow. Engineering returns a sized β, ΔP-transmitter URL, expected accuracy, and ship window within one business day; lead time 5–7 business days from the factory.