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HQ-JL Standard orifice flow meters can be used to measure the flow rates of gases, steam, liquids, and natural gas, and are widely used in process control and measurement in fields such as petroleum, chemical, metallurgical, power, heating, and water supply. This is a type of standard throttling device with the most specifications, which is the simplest and most adaptable product among throttling devices. It is widely used in various fluid, especially gas flow measurement. Its design, manufacturing, and use comply with the international standard IS05167 and are calibrated according to the national standard JJG64097. Standard orifice plates can be divided into three types based on pressure measurement methods: corner joint pressure measurement (including ring chamber pressure measurement and separate drilling pressure measurement), flange pressure measurement, and radial distance pressure measurement (D-D/2). Currently, there are two commonly used methods on site: ring chamber pressure measurement and flange pressure measurement.
Design and manufacture according to the national standard GB/T2624-93
According to the national verification regulation JJG 640-94 for factory inspection
● Pressure measurement methods: corner joint pressure measurement, flange pressure measurement, radial distance pressure measurement
Basic accuracy: Soil 0.5%, ± 1.0%, Soil 1.5%
● Flow range: ≥ 1:15
● Nominal pressure: 0.6, 1.0, 1.6, 2.5, 4.0, 6 4. 10. 16/32 (MPa)
Tested media: water, air, natural gas, saturated steam, superheated steam, other mixed gases
Temperature of the tested medium: conventional -10 ℃~+450 ℃
(1) Schematic diagram of standard orifice plate structure for pressure measurement in the ring chamber:
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(2) Schematic diagram of flange pressure gauge standard orifice plate structure:
Flange pressure tapping has the advantages of simple assembly, convenient installation, and easy removal of dirty media at the pressure tapping port compared to corner tapping. It is widely used in the flow measurement, control, and regulation of various media in industries such as petroleum and chemical.
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4. Selection:
HQ-JL Standard Orifice Flow Meter Selection Table
| HQ-JL- | Orifice Plate Flowmeter | |||||||||||||
| Type of Throttling Element | O | Standard orifice plate | ||||||||||||
| N | Standard nozzle | |||||||||||||
| LN | Long nozzle | |||||||||||||
| B | Balanced orifice plate | |||||||||||||
| S | Pressure reducing orifice plate | |||||||||||||
| T | Quarter round perforated plate | |||||||||||||
| E | Annular orifice plate | |||||||||||||
| F | Welding orifice plate | |||||||||||||
| G | Ring type orifice plate | |||||||||||||
| M | Concealed orifice plate | |||||||||||||
| Process Connection | -P | Welded type | ||||||||||||
| -K | Clamp connection | |||||||||||||
| -H | Flange clamping type | |||||||||||||
| -S | Flat welding flange type | |||||||||||||
| -W | Welding flange type | |||||||||||||
| Structural Form | T | Integrated * (with matching flange/gasket/fastener) | ||||||||||||
| Z | Integrated * (without matching flanges/gaskets/fasteners) | |||||||||||||
| W | Integrated direct welding type* | |||||||||||||
| S | Split type * (with matching flange/gasket/fastener) | |||||||||||||
| X | Split type * (without matching flanges/gaskets/fasteners) | |||||||||||||
| F | Split direct welding type* | |||||||||||||
| Nominal Diameter | □ | DN20-2000 (See the comparison table of nominal diameter numbers for details) | ||||||||||||
| Body Material | Q | SS304 | ||||||||||||
| L | SS321 | |||||||||||||
| A | SS316 | |||||||||||||
| C | 20# | |||||||||||||
| G | 20#((Iron alloy)) | |||||||||||||
| D | Q235((Iron alloy)) | |||||||||||||
| B | 15CrMoG | |||||||||||||
| E | 1Cr5Mo | |||||||||||||
| F | 16Mn | |||||||||||||
| H | HC276 | |||||||||||||
| P | PTFE | |||||||||||||
| M | Monel | |||||||||||||
| S | Other materials | |||||||||||||
| Material of Throttling Element | Q | SS304 | ||||||||||||
| L | SS321 | |||||||||||||
| A | SS316 | |||||||||||||
| B | 15CrMoG | |||||||||||||
| E | 1Cr5Mo | |||||||||||||
| F | 16Mn | |||||||||||||
| H | HC276 | |||||||||||||
| P | PTFE | |||||||||||||
| M | Monel | |||||||||||||
| W | SS316+tungsten carbide spray coating | |||||||||||||
| T | Wear-resistant alloy steel | |||||||||||||
| S | Other materials | |||||||||||||
| Material of Pressure Port | Q | SS304 | ||||||||||||
| L | SS321 | |||||||||||||
| A | SS316 | |||||||||||||
| B | 15CrMoG | |||||||||||||
| E | 1Cr5Mo | |||||||||||||
| F | 16Mn | |||||||||||||
| H | HC276 | |||||||||||||
| P | PTFE | |||||||||||||
| M | Monel | |||||||||||||
| T | Iron alloy | |||||||||||||
| S | Other materials | |||||||||||||
| Flange Standard | 0 | Meaningless (for direct welding selection) | ||||||||||||
| 1 | HG20592-2009 | |||||||||||||
| 2 | HG20615-2009 | |||||||||||||
| 3 | GB/T9115-2010 | |||||||||||||
| 4 | JBT81-94 | |||||||||||||
| 5 | ANSI B 16.5 | |||||||||||||
| 6 | Rectangular flange | |||||||||||||
| 7 | GB/T9119-2000 | |||||||||||||
| 8 | Other types | |||||||||||||
| Pressure Rating | □ | Pressure level (see pressure level number comparison table for details) | ||||||||||||
| Flange sealing surface | 0 | Meaningless (for direct welding selection) | ||||||||||||
| 1 | RF | |||||||||||||
| 2 | RJ | |||||||||||||
| 3 | MF | |||||||||||||
| 4 | FF | |||||||||||||
| 5 | TG | |||||||||||||
| 6 | Other | |||||||||||||
| Measurement Level | J | Quantitative | ||||||||||||
| H | Standard | |||||||||||||
| Pressure Port Specifications | 1 | 1/2”NPT thread | ||||||||||||
| 2 | 3/4”NPT thread | |||||||||||||
| 3 | 2” flange connection | |||||||||||||
| 4 | Socket welding - connecting pipeΦ14 | |||||||||||||
| 5 | Socket welding - connecting pipeΦ18 | |||||||||||||
| 6 | Socket welding - connecting pipeΦ23 | |||||||||||||
| 7 | Direct welding - takeoverΦ14 | |||||||||||||
| 8 | Direct welding - takeoverΦ18 | |||||||||||||
| 9 | Direct welding - takeoverΦ23 | |||||||||||||
| Traffic Compensation | T | Temperature compensation | ||||||||||||
| P | Pressure compensation | |||||||||||||
| I | Temperature and pressure compensation | |||||||||||||
Comparison Table of Nominal Diameter Numbers
| Nominal Diameter | DN20 | DN25 | DN40 | DN50 | DN65 | DN80 | DN100 | DN125 | DN150 | DN200 | DN250 | DN300 |
| DNmm | ||||||||||||
| Marker | 0A | 1 | 0B | 2 | 0C | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| Nominal Diameter | DN350 | DN400 | DN450 | DN500 | DN600 | DN700 | DN800 | DN900 | DN1000 | DN1200 | DN1400 | |
| DNmm | ||||||||||||
| Marker | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 |
Comparison Table of Pressure Level Numbers
| Pressure Rating | 0.25mpa | 0.6mpa | 1.0mpa | 1.6mpa | 2.5mpa | 4.0mpa | 6.3mpa | 10mpa | 16mpa |
| Marker | A | B | C | D | E | F | G | H | J |
| Pressure Rating | 25mpa | 150LB | 300LB | 600LB | 900LB | 1500LB | 2500LB | Other | |
| Marker | K | L | M | N | P | Q | R | S |
The integrated pressure tapping valve, three valve group, and pressure tapping short pipe are welded to the flow body as a complete set for supply. The material of the pressure tapping short pipe/pressure tapping valve/three valve group is the same as that of the pressure tapping port (according to the on-site process requirements, the pressure tapping valve can choose socket welded globe valve, socket welded gate valve or other types and materials of valves). The matching flange material is the same as that of the on-site pipeline material, and the transmitter is matched according to user needs.
**The split type does not include all installation accessories. When ordering, it should be matched according to user needs, and the matching flange material should be the same as the on-site pipeline material. It is recommended to use the split type for steam measurement.
***The selection code for nominal diameter DN32 is 0D.
5. Installation:
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Installation Diagram
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