FAQ - Regulators
Pressure regulators are central to stable and safe gas and liquid systems. Below we answer frequently asked questions about pressure-reducing, back-pressure, cylinder, high-pressure, dome-loaded and vaporising regulators supplied by Ingenieursburo Gommer.
A pressure-reducing regulator takes a variable higher inlet pressure and maintains a lower downstream pressure. It automatically adjusts its valve opening as flow demand and inlet conditions change. View Pressure Regulators on the Gommer website.
A pressure-reducing regulator controls downstream pressure. A back-pressure regulator controls pressure upstream of itself by opening when upstream pressure rises above its set point. View Back Pressure Regulators on the Gommer website.
No. A back-pressure regulator is a modulating control device designed to continuously regulate upstream pressure. A relief valve is primarily a safety device intended to open when a defined pressure limit is exceeded.
A cylinder regulator connects to a compressed-gas cylinder and reduces its high storage pressure to a useful working pressure. Cylinder inlet connections depend on gas type and local cylinder standards. View Cylinder Regulators on the Gommer website.
A single-stage regulator reduces pressure in one regulating stage. A two-stage regulator performs the reduction in two consecutive stages, generally providing better outlet-pressure stability as cylinder pressure decreases.
High-pressure regulators are designed for inlet and/or outlet pressures beyond those of general instrumentation regulators. Applications include gas storage, hydrogen, high-pressure testing and specialist process systems. View High Pressure Regulators on the Gommer website.
A dome-loaded regulator uses gas pressure acting on a diaphragm or piston to provide the regulating force instead of relying only on a mechanical spring. This can provide high flow capacity and enable remote or pilot control. View Dome Loaded Regulators on the Gommer website.
A vaporising regulator combines pressure reduction with heat input. It is used when a liquefied or condensable sample must be converted to a gas without uncontrolled cooling and phase separation. View Vaporizing Regulators on the Gommer website.
Important data include medium, inlet-pressure range, desired outlet pressure, maximum flow, temperature, body and seal compatibility, connection sizes, required cleanliness and hazardous-service requirements.
Cv indicates flow capacity. A larger Cv generally allows more flow for a given pressure drop, but selecting the largest available Cv is not automatically better because an oversized regulator can provide poorer control at low flow.
Droop is the reduction in controlled outlet pressure as flow demand increases. It is a normal characteristic of self-operated regulators, so flow curves are more useful than a single nominal set-pressure value when precise performance matters.
Supply pressure effect describes the change in outlet pressure caused by changes in inlet pressure. It is particularly relevant to cylinder service because cylinder pressure gradually falls during use.
Lock-up is the outlet pressure reached when downstream flow stops and the regulator closes. It is normally slightly above the flowing set pressure.
A continuing pressure increase after the regulator has closed is often called creep. A common cause is contamination or damage at the regulator seat. Upstream filtration can substantially reduce this risk. View Filters on the Gommer website.
No. A regulator is a control device and should not be relied upon for positive process isolation. Separate isolation valves should be installed where required. View Valves on the Gommer website.
Many regulator designs are suitable for liquids, but suitability is model-dependent. Liquid viscosity, cavitation, pressure drop and seal compatibility may become important.
Gas-regulator sizing considers inlet pressure, outlet pressure, required flow, gas properties and the regulator's flow coefficient or published flow curves. At high pressure ratios, choked or sonic flow can occur.
A flow curve shows how outlet pressure changes as flow increases. It reveals droop and usable flow range far better than a catalogue's single Cv value.
A diaphragm provides a relatively large sensing area and is commonly used where sensitivity and accurate low-pressure control are important. A piston can be well suited to higher outlet pressures and compact high-pressure designs.
A balanced valve is designed so changes in inlet pressure exert less net force on the valve mechanism. This can reduce supply-pressure effect and improve outlet-pressure stability.
Common materials include brass, 316/316L stainless steel, Monel, Hastelloy and selected nickel alloys. Availability depends on manufacturer and regulator family.
Depending on design and service, seat materials can include PCTFE, PEEK, PTFE and other polymers, while specialised regulators may use different or metal seating arrangements.
Metal diaphragms provide excellent containment and are widely used for high-purity, corrosive and hazardous gases. Elastomer diaphragms are suitable for many general industrial applications.
Yes, but regulators intended for oxygen service must be specifically selected, cleaned and prepared for oxygen. Oxygen service must be stated at the time of enquiry and ordering.
Yes. Regulators are widely used in hydrogen production, storage, testing, fuel-cell and high-pressure systems. Pressure rating, materials, seat design and leakage requirements must all be considered.
Chemical compatibility must be evaluated for the body, diaphragm, seat, seals and exposed internal components. Depending on gas composition, materials such as 316L, Monel or Hastelloy may be required.
High-purity regulators typically use carefully controlled internal surface finishes, metal diaphragms, low internal volume and suitable cleaning and packaging procedures.
Analytical systems usually benefit from low internal volume, stable outlet pressure and suitable materials that do not contaminate or adsorb the sample. For condensable samples, heated or vaporising regulators may be necessary. View Sampling and Systems on the Gommer website.
Many gases change temperature during pressure reduction due to the Joule-Thomson effect. Large pressure drops can cause considerable cooling, potentially resulting in condensation, freezing or regulator instability.
For many regulator applications, yes. Small particles can damage soft regulator seats and cause leakage or creep. View Filters on the Gommer website.
It depends on the system. If the regulator's maximum possible downstream pressure could exceed the allowable pressure of downstream equipment, an independent pressure-protection device may be required.
Many industrial regulators are designed to be serviced using manufacturer repair kits containing seats, seals and diaphragms. Critical or high-pressure regulators should be tested after servicing.
Depending on manufacturer and model, documentation may include certificates of conformity, material certificates, cleanliness certificates, pressure-test documentation and oxygen-clean documentation.
Yes. Assemblies can combine regulators with isolation valves, filters, pressure gauges, relief devices, manifolds, tubing and fittings and can be tested as a complete unit. View Contact and Engineered Assemblies on the Gommer website.
Send us the medium, inlet-pressure range, desired outlet pressure, required flow, operating temperature and material or cleanliness requirements. Ingenieursburo Gommer can compare suitable products across several regulator manufacturers.