Marsh Bellofram

Precision air pressure regulator designed for accurate, highly repeatable output pressure with very low sensitivity to changes in supply pressure, ambient temperature and flow.

Use it whenThis is the reference precision regulator and the right starting point whenever a pneumatic instrument, a test stand or a loading pressure has to hold steady while the supply or the ambient conditions move around. Choose it over a general purpose regulator when the setpoint drifting is the actual complaint.

High-flow precision regulator with a balanced supply valve using the Bellofram rolling diaphragm design, and an aspirator tube that adjusts air supply according to flow velocity.

Use it whenMove up from a Type 10 when the downstream demand is large or swings hard, for example a large actuator or a bank of devices, and a precision regulator would otherwise droop. The aspirator tube is what holds the setting as flow changes, so this is the pick when accuracy has to survive high flow.

Back pressure regulating version of the Type 70.

Use it whenUse a back pressure regulator when you are controlling the pressure upstream of the device rather than downstream, which is the case on relief, bypass and venting duties. It is easy to specify the wrong one, so confirm which side of the valve the controlled pressure is on.

Devices that convert an electrical control signal into a proportional pneumatic output pressure.

Use it whenSpecify one of these where a control system output has to drive a pneumatic actuator, positioner or loading pressure. Get the exact model and signal range from Marsh Bellofram, since I could not verify individual model numbers well enough to list them here.

Gauges for reliable pressure measurement with water, oil, air, gas and other non-corrosive media, from vacuum and compound ranges upward.

Use it whenThis is the everyday gauge for utilities and non-corrosive service. Use it where the media is benign and there is no vibration or pulsation problem, and step up if either of those is present.

Gauges designed for reliable measurement in harsh and demanding industrial and OEM environments, particularly where pulsation and vibration are a concern.

Use it whenSpecify liquid filled the moment pulsation or vibration enters the conversation, for example on a positive displacement pump or a compressor. A dry gauge in that service will have an unreadable needle and a short life, and it is the single most common gauge failure we get called about.

Stainless gauges built for extended life in harsh and corrosive sour gas hydrogen sulphide environments.

Use it whenUse these where sour service is specified. This is not a preference, it is a material compliance requirement, so match the specification rather than substituting a stainless gauge that merely looks equivalent.

Process gauges, described on the site as having over 125 years of proven experience behind them.

Use it whenChoose a process gauge where the installation is a permanent plant asset expected to be read and maintained for years, rather than an OEM or utility point.

Diaphragm-element gauges for low pressure measurement.

Use it whenReach for a diaphragm element when the pressure is too low for a bourdon tube to resolve usefully. This is the same reasoning that puts a Magnehelic on an air duct, applied to a Marsh gauge body.

Value-positioned pressure gauge line within Marsh Instruments.

Use it whenOffer this when the customer is buying on price for a non-critical point and would otherwise go to a commodity import. Do not put it on a critical or severe service point.

High and low pressure regulator products, including general purpose gas regulators, back pressure and pressure relieving regulators, flow controllers, manifold systems and instrument air regulators.

Use it whenThis is the natural gas pressure regulation line, spanning distribution system regulators through to instrument air on the pad. Establish first whether the duty is reducing, back pressure relieving or flow control, because those are three different devices and the wrong one will not simply perform poorly, it will not work.

Instrumentation used on the well pad and beyond, including control valves, level controls, level safety indicators, pressure relief valves, gauges, needle valves, pilots and accessories.

Use it whenUse this business unit when the scope is production equipment on the pad rather than distribution, for example separator level control and relief. It is the right route for a wellsite package where regulators alone will not cover the bill of materials.

Flame arrestors, tank venting accessories, burners and specialty fabrication services.

Use it whenBring this in where fired equipment and tank venting are in scope, such as heater treaters and tank batteries. Flame arrestor and vent selection is code-driven, so it belongs with the safety review rather than the instrument list.

Check valves, stuffing boxes and related equipment.

Use it whenThis is production mechanical equipment rather than instrumentation, and it comes up on rod-pumped wells. Worth knowing the group can supply it when a customer is consolidating vendors.

Choke assemblies, described on the site as industry standard.

Use it whenChokes are a wellsite flow control item. Same logic as above, it is a reason the group can cover more of a pad scope from one source.

Automation and electrical safety devices including relays and monitors.

Use it whenReach for these when the requirement is protection of a motor or a supply, for example phase loss, phase reversal or voltage monitoring. It is a cheap device that prevents an expensive failure, so it belongs in the conversation whenever a customer has burned a motor.

Industrial timers, counters and PID controllers.

Use it whenUse these for standalone sequencing and single-loop control where a PLC is not justified. A timer and a controller on a small skid is often the right answer instead of a control system.

Brushless DC tachometers, instrument-grade DC tachometers and rotary encoders.

Use it whenSpecify a tachometer where speed has to be measured as an analog value for control or indication, and an encoder where position or counted increments are wanted. Instrument-grade is the choice when the tachometer output feeds a measurement rather than just an indication.

AC and DC tachometers for velocity measurement applications.

Use it whenA second tachometer source within the group. Choose between ServoTek and Westcon on the electrical output and mechanical mounting the machine needs rather than on brand.

The rolling diaphragm design used in Bellofram's own balanced supply valves, offered as a component.

Use it whenThis is an OEM design-in item. It comes up when a machine builder needs long-stroke, low-friction, leak-free actuation that a piston seal cannot deliver. The same design is what makes the Type 70 regulator immune to supply pressure changes, which is a useful proof point.

Diaphragms, closed cell silicone sponge and solid silicone in application-specific formulations.

Use it whenRoute these to a design engineer, not a maintenance buyer. The value is the application-specific formulation, so the conversation starts with media, temperature and duty cycle rather than a part number.