Orifice Plate Flow Sensor — BF01
The orifice plate is the most widely used flow meter in history. BF01 is a standard throttling DP element manufactured and sized to international standards, covering DN15–DN1000+ with pressures up to 64 MPa and temperatures from -185 °C to +850 °C. Simple, reliable, low cost and maintenance-free.
Specifications
| Accuracy | Per ISO 5167 / JJG 640 |
| Nominal size | DN15 – DN1000 mm or larger |
| Working pressure | Up to 64 MPa |
| Working temperature | -185 to +850 °C |
| Media | Single-phase; some mixed-phase |
| Types | Standard, integral, annular, segmental, eccentric, restrictive, balanced |
| Straight run | Typically 10D upstream / 5D downstream |
Details
Working Principle
Based on energy conversion in a sealed pipe (Bernoulli equation): Qv = K × C × √ΔP, Qm = Qv × ρ. A concentric bore in the plate creates a differential pressure across the flange or corner taps; measuring ΔP yields the flow. The orifice plate is essentially a single-hole "balanced" plate, while a balanced flow sensor is a multi-hole plate.
Common Plate Types
- Standard orifice plate: conforms to GB/T 2624, verified to JJG 640; corner, flange or radial taps
- Segmental (圆缺): for wet gas and dirty media, avoids carryover blockages
- Eccentric orifice: for wet steam, producer/coke/blast-furnace/mixed gas, water-bearing oil products and particle-laden liquids
- Integral (内藏, DN≤50): plate and measuring tube as one piece
- Restrictive (限流): used for pressure reducing / flow limiting
Integral & Restrictive Variants
BF01-M 内藏式孔板（BF01-MF 一体型 / BF01-MS 分体型）：高准确度小管径应用（DN15~40 一体型、DN50+ 法兰取压分体型），精度 1.0% 可达 ±0.5%，重复性 0.1%。BF01-X 限流孔板（XS 单级 / XD 多级）：降压限流、降低噪音、避免汽蚀，常规尺寸达 24 in（DN600）。
Installation
- Straight-run: typically 10D upstream, 5D downstream
- Horizontal or vertical pipe, integral or remote transmitter
- Media: gas, liquid or steam