Pressure Gauges & Thermometers
Marsh Instruments has manufactured precision pressure gauges and thermometers since 1865 — over 160 years of measurement experience. Their products are used in oil and gas, chemical, power generation, and industrial applications worldwide where accuracy, durability, and reliability are non-negotiable.
Why Accurate Local Measurement Matters
Local pressure gauges and thermometers provide the operator with direct, immediate visual indication of process conditions without relying on transmitters, control systems, or power supply. They are the first check when something is wrong in the field — and they must be accurate and readable in all conditions.
A gauge that reads incorrectly, sticks, or becomes illegible due to vibration or process fluid ingress creates safety risks and leads to incorrect field decisions. Marsh Instruments gauges are built to withstand the vibration, pressure spikes, and ambient conditions of oilfield service.
Product Range — Marsh Instruments
Pressure Gauges
Marsh Instruments manufactures a full range of Bourdon tube pressure gauges for oilfield and industrial service. Available in dry and glycerin-filled versions — glycerin fill dampens pointer vibration for easier reading in high-vibration pump and compressor applications.
Available configurations:
- Dial sizes: 2½”, 4″, 6″ standard
- Pressure ranges: vacuum through 10 000 PSI
- Process connections: ¼” and ½” NPT standard
- Case materials: ABS plastic, stainless steel
- Wetted parts: brass standard; stainless steel and Monel for corrosive service
- Glycerin-filled for vibration service
- Pressure snubbers available for pulsating service
Thermometers
Marsh Instruments bimetal thermometers provide local temperature indication in pipelines, vessels, and heat exchangers. The bimetal element is accurate, robust, and requires no power supply.
Available configurations:
- Dial sizes: 3″, 5″ standard
- Temperature ranges: -40°C to 538°C depending on model
- Stem lengths: 2½” to 12″ standard
- Connection: ½” NPT standard
- Adjustable angle models for ease of reading in confined spaces
Digital Pressure Indicators
The Marsh Instruments Digital Pressure Indicator is a portable, hand-held testing and calibration instrument. It measures pressure to 50 PSIG at ±0.25% reading accuracy — suitable for field calibration of pressure gauges and transmitters.
Key Specifications
| Parameter | Pressure Gauges | Thermometers |
|---|---|---|
| — | — | — |
| Range | Vacuum – 10 000 PSI | -40°C – 538°C |
| Accuracy | ±1% ASME Grade B | ±1% full scale |
| Dial sizes | 2½”, 4″, 6″ | 3″, 5″ |
| Fill | Dry or glycerin | N/A |
| Wetted materials | Brass, SS, Monel | SS standard |
| Standards | ASME B40.100 | ASME B40.200 |
Why Source Through Proxima
Proxima stocks Marsh Instruments pressure gauges and thermometers in standard oilfield configurations for fast delivery across Azerbaijan and the Caspian region. We supply gauges calibrated and tagged to your specification.
Frequently Asked Questions
Q: When should I use a glycerin-filled gauge instead of a dry gauge?
Use glycerin fill wherever the gauge is subject to vibration — pump discharge lines, compressor manifolds, and engine-mounted applications. The glycerin dampens pointer oscillation, making the gauge readable and extending its service life by reducing mechanical fatigue on the Bourdon tube.
Q: What is a pressure snubber and when is it needed?
A pressure snubber is a restriction fitting installed between the process and the gauge to dampen pressure spikes and pulsations. Use it on reciprocating pump discharge lines and anywhere sharp pressure spikes occur — without a snubber, spikes can overrange and damage the Bourdon tube.
Q: Can pressure gauges be supplied for H₂S service?
Yes. Gauges with stainless steel or Monel wetted parts are available for sour service. Specify H₂S concentration and pressure when ordering.
Q: What dial size should I specify?
4″ is the standard choice for most field applications — readable from a safe distance without being oversized. Use 2½” for compact installations and 6″ for panel mounting or high-visibility locations.
