Natural Gas Swirl Flow Meter
Natural Gas Custody Swirl
Accuracy of ±0.5% of rate
Temperature service −40 to +250 °C
Turndown ratio of 1:30
- Line sizes DN25 to DN300
- Flange ratings PN16 to PN100 (ANSI 150 to 1500 LB)
- Body materials 316L stainless

The Natural Gas Swirl Flow Meter measures natural gas on M&R stations, CHP feed lines, and factory inlets. Built-in T+P compensation outputs Nm³/h with on-board AGA-style compressibility correction.
316L stainless wetted parts cover dry pipeline gas. The 3D+2D straight-pipe install fits tight skid layouts. CNEX Ex d IIC T6 Gb ships on every order.
Benefits
- 3D / 2D straight run: 3× DN upstream / 2× DN downstream vs vortex 10D / 5D; ~70% less spool on tight M&R retrofits.
- ±0.5 % of rate: standard build delivers ±0.5 % at 1:30 turndown; fits distribution billing reconciliation.
- Built-in T+P + compressibility: integrated RTD, pressure, and gas-composition computer output Nm³/h directly on 4-20 mA.
- Low-density / H₂-blend ready: precession stays linear where Karman shedding fails; covers NG, biomethane, H₂-blend distribution.
- Factory-calibrated to gas composition: pre-loaded against latest chromatograph analysis on the order; P/T locked before production.
- Hazardous-area certification: CNEX Ex d IIC T6 Gb (Zone 1, gas group IIC) optional; IP65/IP66/IP67 + EMC 2014/30/EU standard.
- Lead time: every configuration ships in 5–7 business days from factory.
Configure your build.
Select the specs; the LUXB 13-position model code and ballpark price update live. Submit to engineering for verified sizing against the gas analysis (reply within 4 business hours).
Your Configuration
✓ ISO 9001 calibration certificate with each meter
✓ Gas analysis reviewed by application engineer
✓ Engineering replies within 4 business hours
Typical applications
M&R Station Retrofits
Drops into M&R stations where existing skid is too short for a vortex meter’s 10D upstream.
Distribution Gas Inlets
Factory/commercial gas inlets downstream of city-gate. T+P+compressibility outputs Nm³/h to DCS. DN50–DN200 at PN16–PN64.
Biomethane Grid Injection
Upgraded biomethane (>96% CH₄) into distribution networks. 316L standard; Hastelloy C for H₂S-bearing raw biogas on same body.
Hydrogen-Blend Networks
Precession stays linear at low H₂-blend density. Factory-calibrated against blend composition; material spec per H₂ fraction.
Specifications
Performance
| Reference volume accuracy | ±0.5 % of rate standard · ±1.0 % of rate / ±1.5 % of rate economy |
|---|---|
| Repeatability | ±0.2 % |
| Turndown ratio | 1:10 – 1:30 · maximum for swirl |
| Built-in temperature sensor | Integrated RTD (T compensation) |
| Built-in pressure transducer | Integrated (P compensation) |
| Compressibility correction | Built-in; standard-condition volume (Nm³/h) computed in-meter without an external flow computer |
Process & Environment
| Medium | Natural gas · biomethane · biogas · low-density / hydrogen-blend gas |
|---|---|
| Pressure range | 1.6 – 25 MPa · PN16 to PN250 / ANSI 150 to ANSI 2500 LB |
| Medium temperature | T1: -45 to +80 °C · T2: -45 to +250 °C · T3: -45 to +350 °C |
| Ambient temperature | -20 to +65 °C |
| Ambient humidity | 5 % – 90 % RH non-condensing |
| Enclosure rating | IP65 / IP66 / IP67 selectable |
Electrical & Output
| Power supply | +6–24 VDC (≤10 mA; RS485 adds 0.6 mA) · 3.6 V Lithium battery option (≤0.3 mA) |
|---|---|
| Analogue output | 4–20 mA (3-wire or 2-wire); Nm³/h standard-condition volume, isolated |
| Pulse output | 3-wire or pulse-equivalent |
| Digital output | RS485 Modbus RTU · HART · 4G IoT |
| Local display | Chinese / English dot-matrix LCD; working-condition flow, standard-condition flow, totalizer, instantaneous P, T |
| Remote distance | Up to 1000 m sensor-to-display (LUXB-F remote version) |
Materials & Construction
| Body material | 304 SS standard · 316L · Hastelloy C · custom |
|---|---|
| Sensor material | 304 SS standard · 316L · Hastelloy C · custom |
| Piezoceramic sensor pair | Dual element, mounted outside the bore; measures precession period from behind the pipe wall |
| Transmitter housing | Cast aluminum alloy with polyester anti-corrosion coating |
| Transmitter style | Integral (LUXB-S) or Remote (LUXB-F, sensor-to-display up to 1000 m) |
| Connection | Flanged (FL) standard · Sanitary clamp (LW) · custom |
Flow range by pipe size.
Reference volume in Nm³/h at standard conditions (101.325 kPa, 0 °C; IUPAC STP). Tabulated at 1.6 MPa operating pressure with methane composition; the engineering team validates sizing against the live gas analysis, H₂ fraction, and operating range at quote stage.
| Pipe size | Minimum (Nm³/h) | Typical range (Nm³/h) | Maximum (Nm³/h) |
|---|---|---|---|
| DN50 (2″) | 140 | 280 – 2,100 | 4,200 |
| DN80 (3″) | 360 | 720 – 5,400 | 10,800 |
| DN100 (4″) | 560 | 1,120 – 8,400 | 16,800 |
| DN150 (6″) | 1,260 | 2,520 – 18,900 | 37,800 |
| DN200 (8″) | 2,240 | 4,480 – 33,600 | 67,200 |
| DN250 (10″) | 3,500 | 7,000 – 52,500 | 105,000 |
Installation
Five rules keep the LUXB on-spec.
- 3D upstream / 2D downstream clear of disturbance Full-bore pipe with no valves, tees, or orifice plates in the window.
- Provide gas analysis at quote time Compressibility correction needs methane, ethane, propane, CO₂, N₂, H₂ fraction at working P/T.
- Confirm hazardous-area zone on quote CNEX Ex d IIC T6 Gb (Zone 1, gas group IIC) ships standard for hazardous orders.
- Filter ahead of meter on dirty-gas lines String: [Valve] → [Expansion] → [Filter] → [≥3D] → [LUXB] → [≥1D] → [Valve].
- Wire only the loop you need T+P+compressibility read on-board; field wiring is 4-20 mA (or RS485/HART) only.
Frequently asked questions
When should I specify a swirl meter instead of a vortex meter for natural gas?
What hazardous-area certification ships with the natural-gas swirl meter?
Does the LUXB compute standard-condition volume (Nm³/h) in the meter?
What pipe sizes, pressure classes, and temperature ranges does the natural-gas swirl meter cover?
Can this meter handle biomethane, biogas, or hydrogen-blend natural gas?
How much shorter can the M&R station spool become with a swirl meter?
What lead time should I plan for?
Need help sizing the natural-gas build?
Send pipe size, straight-run length, P/T, design Nm³/h, gas analysis (incl. H₂ fraction). Engineer replies in 4h with Nm³/h, LUXB model code, K-factor, price.