High Temperature Vortex Flow Meter

Up To 500 °C Vortex Build

Accuracy of ±0.5% VRd
Temperature service up to 500 °C
Turndown ratio of 1:70

  • Line sizes DN15 to DN600
  • Flange ratings PN16 to PN160 (ANSI 150 to 2500 LB)
  • Body materials 316L stainless or Hastelloy C
↓ Request datasheet (PDF)
LUGB Vortex Flow Meter; instrument body with display head

The High-Temperature Vortex Flow Meter handles service from -45 °C up to 500 °C. The LUGB body in 316L or Hastelloy C handles superheated steam, hot-gas, and hot-oil loops past standard saturated-steam meter ceilings.

Ceilings of 350, 400, 500 °C are factory-locked via T2/T3/T4 build codes. Built-in T+P compensation outputs mass flow in kg/h. CNEX Ex d IIC T6 Gb hazardous-area option on every configuration.

Benefits

  • VRd accuracy: the LUGB-VRd version delivers ±0.5 % accuracy across a 1:70 turndown, sufficient for energy billing on superheat and hot-gas service.
  • Built-in T+P compensation: an integrated RTD and pressure transducer feed the on-board flow computer, outputting mass flow directly in kg/h with no external multivariable transmitter.
  • Wetted-parts options: 316L stainless covers most high-temperature service; Hastelloy C is the option for chloride or acid carry-over.
  • Temperature ceiling: ceilings of 350, 400, and 500 °C are factory-locked through the T2, T3, and T4 build codes; specify above peak operating temperature, not at it.
  • Hazardous-area certification: CNEX Ex d IIC T6 Gb (flameproof, Zone 1, gas group IIC) ships optionally on every order.
  • Lead time: every configuration ships within 5–7 business days from the factory.

Temperature ceiling

Three ceilings; 350 °C, 400 °C, and 500 °C; selected by the continuous medium temperature with margin for peak transients. Order above the peak, not at it. Locked at the factory; cannot be upgraded in the field. For service below 250 °C, see the standard flanged or saturated-steam model instead.

  1. Up to 350 °C; T2 build-45 to 350 °C Superheated steam and hot-gas lines up to 350 °C. The entry point into the high-temperature configuration; 316L stainless wetted parts by default.
  2. Up to 400 °C; T3 build-45 to 400 °C Main superheated-steam headers up to 400 °C, thermal-oil loops at film temperature, hot-gas boiler exit. 316L is standard; Hastelloy C is the upgrade when the stream is corrosive.
  3. Up to 500 °C; T4 build-45 to 500 °C The highest continuous medium temperature in the LUGB family. The right pick for power-plant superheated-steam tail-end service and any stream with a peak up to 500 °C. 316L standard; Hastelloy C when corrosion or oxidation drives the material choice.

Configure your build.

Your configuration

LUGB-VRd-15-U-A-P-3-T4-1-4-T-H2-S
Pipe sizeDN150
VariantLUGB-VRd
Temperature codeT4; up to 500 °C
Wetted material316L stainless
Pressure classH2; PN25 / ANSI 300
Process mediaSteam
CompensationT + P compensation
Hazardous areaStandard (non-Ex)
Estimated unit price
Verified after engineer review
$3,614
Total (×1)
$3,614

Flow range by pipe size.

Mass values are for saturated steam at 160 °C / 0.5 MPa (3.26 kg/m³). Volume values apply across gas service. Send your medium, line pressure, and operating temperature on the quote; the engineering team sizes the exact DN with the K-factor curve.

DNInchesVelocity (m/s)Gas volume (m³/h)Saturated steam mass (kg/h)
DN151/2″5 – 503 – 3010 – 100
DN203/4″4 – 604 – 5013 – 163
DN251″4 – 606 – 10020 – 326
DN321-1/4″3 – 709 – 18029 – 587
DN401-1/2″3 – 7014 – 28046 – 913
DN502″3 – 7020 – 40065 – 1,304
DN652-1/2″3 – 7035 – 700114 – 2,282
DN803″3 – 7060 – 1,200180 – 3,912
DN1004″3 – 7090 – 2,000294 – 6,520
DN1255″3 – 70120 – 2,400391 – 7,824
DN1506″3 – 70200 – 5,000652 – 16,300
DN2008″3 – 70350 – 8,0001,141 – 26,080
DN25010″3 – 70550 – 11,0001,793 – 35,860
DN30012″3 – 70800 – 18,0002,608 – 58,680
DN35014″3 – 701,100 – 24,0003,586 – 78,240
DN40016″3 – 701,400 – 31,0004,564 – 101,060
DN50020″3 – 702,300 – 49,0007,500 – 159,740
DN60024″3 – 703,400 – 70,00011,084 – 228,200

Specifications

Performance

Measurement principleKarman vortex street
Accuracy class E±0.75% of actual (high-accuracy code)
Accuracy class A±1.0% of actual (standard)
Accuracy class B±1.5% of actual (gas / steam class)
VRd version±0.5% of actual, 1:70 turndown (2024 Top-10 award)
Turndown; standardUp to 1:15 typical
CalibrationFactory certificate traceable to national standards

Temperature codes

T2 code-45 °C to +350 °C; high-temp (superheated steam)
T3 code-45 °C to +400 °C; ultra high-temp
T4 code-45 °C to +500 °C; super-ultra high-temp
Ambient; transmitter-40 °C to +70 °C housing rating
Build selectionLocked at the factory; cannot be upgraded in the field

Mechanical & flange

Pipe sizeDN10 – DN600 (flanged) · DN15 – DN300 (wafer)
Pressure codesH1 – H25 (1.6 MPa – 25 MPa) · ANSI Class 150 – 2500
Body materialDefault 304 stainless · optional 316L, Hastelloy C, titanium
Sensor materialStandard 316L · optional Hastelloy C
ConnectionFlanged (code 1) · wafer (code 2) · threaded (code 5)
Straight pipe run10D upstream / 5D downstream (standard pipe)

Electronics & compliance

Output4-20 mA · pulse · RS485 Modbus RTU · HART · 4G IoT
Power supply24 VDC · 220 VAC · 3.6 V lithium battery
CompensationTemperature (P code) · temperature + pressure (T code)
Hazardous areaStandard (P code) or explosion-proof (EX code)
HousingCast aluminium alloy with polyester anti-corrosion coating
Transmitter styleIntegral (S code) or remote (F code)

Typical applications

Four zones above 250 °C; where 304 runs out of margin.

Power-plant superheated-steam tail-end

Auxiliary turbine/reheat-leg superheated steam at 400–500 °C, PN40–PN100, 316L wetted, ±0.5 % VRd.

Up to 500 °C
🛢

Thermal-oil / hot oil loops

Heat-transfer fluid 250–400 °C on heaters, polymer reactors, battery dryers; Hastelloy C for chloride/acid.

Up to 400 °C
🏭

Hot-gas and boiler-exit lines

Combustion-air preheat, hot-gas recycle, boiler-exit up to 500 °C; Hastelloy C for oxidisers/acid condensate.

Hot gas · up to 500 °C
🧪

Process superheat and hot condensate

Superheated process steam 250–450 °C, hot condensate return on reactors/reboilers; T+P mass flow kg/h.

Process steam · 250–450 °C

Installation

Six install rules. Temperature ceiling and wetted material lock at the factory; get them right at quote time.

  1. Specify the temperature ceiling above the peak continuous medium T Three ceilings are available; T2 (350 °C), T3 (400 °C), T4 (500 °C); locked at the factory, no field upgrade.
  2. Pick the wetted material by corrosivity 316L covers most high-temperature steam and hot-gas service; Hastelloy C handles chloride, acid condensate, or oxidising carry-over.
  3. Keep the published straight-run discipline 10D upstream and 5D downstream on standard pipe. After a single 90° elbow: 25D / 5D. After two elbows in different planes: 40D / 5D.
  4. Avoid heavily vibrating pipe runs Anti-vibration clamps within 2D upstream and downstream when the run vibrates. Hot pipe with vibration accelerates body fatigue.
  5. Insulate the pipe and body, never the transmitter housing The housing’s -40 to +70 °C ambient rating must stay clear of insulation.
  6. Ramp startup at the boiler or heater manufacturer’s rate The LUGB body tolerates normal power-plant ramps under 10 K/minute, comfortably inside the body’s rated range.

Frequently asked questions

When does the high-temperature build beat the standard flanged LUGB?
Whenever the line runs above 250 °C, or when 304 stainless is not acceptable for the process. The high-temperature build uses the same LUGB hardware with upgraded wetted parts; 316L stainless or Hastelloy C in place of 304; and the temperature ceiling reaches 500 °C. Below 250 °C the saturated-steam model is the better pick; above 500 °C the vortex principle is outside its rated range.
What is the maximum medium temperature this meter handles?
500 °C continuous; the highest medium temperature in the LUGB family. From 400 °C to 500 °C the meter ships with 316L or Hastelloy C wetted parts depending on corrosivity. From 250 °C to 400 °C, 316L is usually enough. Above 500 °C the vortex signal weakens as viscosity drops; an orifice plate with remote seal or an averaging-pitot insertion is the better fit at that point.
Does the 316L or Hastelloy C body affect accuracy?
No. The Karman-vortex bluff body and the piezoelectric sensor sit inside the pipe the same way regardless of wetted material. Vortex flow meter accuracy stays at ±1.0 % on the standard build and ±0.5 % on the LUGB-VRd, with turndown up to 1:70. What 316L or Hastelloy C buys is corrosion and oxidation resistance at high temperature; not a different measurement class.
How is the meter calibrated for high-temperature service?
Every meter ships with a factory calibration certificate traceable to a national-standard reference. The published K-factor stays valid across the rated temperature range; the correction curve is applied inside the transmitter. For critical service, a second calibration point closer to the actual service temperature can be added at order time. Flag it on the line list if it is needed.
How do startup and shutdown transients affect meter life?
The LUGB body and bluff body are matched for thermal expansion through normal ramp cycles. Most power-plant and thermal-oil systems ramp at well under 10 K/minute; comfortably inside the rated range. For unusual service (trip-return cycles with faster ramps), flag the service profile on the quote so the right body and pressure class ships.
What certifications ship with high-temperature orders?
CNEX Ex d IIC T6 Gb (flameproof, Zone 1, gas group IIC, surface-temperature class T6) ships as standard for hazardous-area orders; confirm the zone on the quote. IP65 / IP66 / IP67 ingress protection is available. EMC compliance to the EU Electromagnetic Compatibility Directive 2014/30/EU (Annex II) ships as standard, covering EN IEC 61000-6-1, -6-2, -6-3, -6-4, EN IEC 61000-3-2, and EN 61000-3-3.
Why vortex (not Coriolis or ultrasonic) for a high-temperature line?
Above 400 °C the meter-class field narrows. A Coriolis is capped by tube metallurgy at roughly 400 °C continuous. A clamp-on ultrasonic loses acoustic signal through the oxide scale on hot pipe OD. The LUGB vortex flow meter is rated to 500 °C with 316L or Hastelloy C wetted parts and built-in T+P compensation; typically the right call in the 400–500 °C range.
Is the LUGB suitable as a hot oil flow meter?
Yes; the LUGB Series fits synthetic thermal-fluid heater loops up to 400 °C bulk temperature. 316L stainless wetted parts are standard; step up to Hastelloy C when the fluid carries chloride or acid carry-over. Built-in T+P compensation turns the volumetric reading into a mass-flow signal for plant energy balance. Line pressure is typically PN16 or PN25.

Need help sizing the high-temperature build?

Send DN, design pressure, medium T, area class. Sized, quoted, shipped; 5–7 days from factory.