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WELKER > Instrumentation > Regulators > ATEX/IECEx HR

Where to Use

  • Natural Gas Sampling: Upstream of an analyzer as a standalone pressure control device or part of a conditioning system
  • Places where flammable gases are likely to occur in quantities sufficient to cause a fire or an explosion (AKA Ex areas, hazardous locations, hazardous areas, explosive atmospheres)

EX Out Hazards

Is there something in the air? You may be in an explosive atmosphere. Knowing these hazardous locations require specially designed equipment to reduce the risk of fires and explosions, Welker updated its patented HR-4SS Heated Instrument Regulator specifically for this purpose.

The Welker HR Heated Instrument Regulator is a single-stage, spring-loaded, electrically heated pressure reducing valve designed to provide an analytical system with a conditioned gas sample stream at a safe output pressure and temperature. The HR’s controlled heating compensates for the cooling brought on by the Joule-Thomson effect to prevent condensation and maintain sample integrity. The HR is certified to international standards and the European ATEX Directive, making it safe for global use in Ex areas.

Data Sheet ATEX/IECEx HR
Certificate of ConformityIECEx SIR 16.0072X
EU-Type Examination CertificateSira 16ATEX1221X
Compliant With Internationally Recognized Standards

Safety the World Over

We don’t leave safety to chance, and neither should you! An IECEx-approved certification body rigorously tested and evaluated our HR and regularly audits our manufacturing facilities to ensure compliance with existing international standards. You can be confident in the HR’s safety, reliability, performance, and durability in Ex areas around the world.

Thermostatically Controlled Heating

Turn Up the Heat

Energized by a direct power connection, the thermostatically controlled heating element ensures efficient heat transfer to prevent condensation. Choose from two temperature control ranges so you can set the thermostat above the hydrocarbon dew point of the gas in accordance with industry standards. With the heating element installed to the side of the HR, it’s well-suited to installations with height restrictions.

For your protection, the thermostat is located inside a certified explosion-proof housing and should only be adjusted when de-energized or in a non-hazardous location.

Pressure Control Options

Have it Your Way

Two body styles and multiple pressure control ranges let you adapt the HR to your instrument and application. The threaded HR is diaphragm-sensing for greater sensitivity, giving you more control when setting the outlet pressure. For additional instrument protection, select the cartridge-style option, which provides 40-micron inlet filtration. With a bolted spring housing and body, the piston-sensing HR can handle higher inlet and outlet pressures. Both body styles come with an ergonomic 4-point hand knob, making field adjustments quick, easy, and comfortable. A locknut prevents the spring setting from changing due to vibration to help maintain a constant outlet pressure and flow.


ATEX/IECEX HR Heated Regulator
Materials of ConstructionRegulator Base and Body: 316/316L Stainless Steel (Standard), Others Available
Seals: Varies Based on Customer Specifications and the MAOP and MAOT of the Unit
Temperature RangeAmbient: -31 °F to 140 °F
Process: -20 °F to 68 °F
Connections¼" FNPT
Pressure Control Ranges0–25 psig
0–50 psig
20–100 psig
75–200 psig
Maximum Allowable Operating PressureBolted: 6000 psig @ -265 °F to 400 °F
Threaded: 3600 psig @ -265 °F to 400 °F
Explosive Atmosphere / Hazardous Location Certifications*IECEx Certification (Certificate of Conformity IECEx SIR 16.0072X)
ATEX Certification (EU-Type Examination Certificate Sira 16ATEX1221X)
Group II, Category 2G, Ex db IIB+H2 T3 Gb
Tamb -35 °C to +60 °C
OptionsMounting Bracket
Relief Valve and Pressure Gauge

*To maintain its certifications, the HR must be installed, operated, and maintained in accordance with the instructions in the Welker IOM Manual.

Note: A downstream relief is required.