A process engineer walks up to a newly delivered pump package, glances at the pressure instruments, and already knows what is inside each round case. On most industrial equipment in service today, those small gauges share the same operating principle. For engineers and plant teams who source instruments, the same question always comes up: what is the most common pressure gauge? The short answer is the Bourdon tube pressure gauge. This article explains why that design became the standard across industries, how it works, which alternatives exist, and how to select the right gauge for a particular application.
The Most Common Pressure Gauge Is the Bourdon Tube Type
The Bourdon tube pressure gauge, named after the French engineer Eugène Bourdon who patented the design in 1849, is the most widely used pressure-measuring instrument in the world. It is found in factories, compressor rooms, refineries, water treatment plants, hydraulic systems, and thousands of other installations. The word "pressure gauge" in this discussion refers to the instrument itself, and within that instrument category, the Bourdon tube type is the one you will meet most often.
Well over 150 years after its invention, the basic construction has not changed. It is fully mechanical, needs no power supply, tolerates harsh conditions, and gives a stable local reading. When someone says "a standard pressure gauge," in most cases they are describing a Bourdon tube gauge.
Why the Bourdon Tube Gauge Became the Industry Standard
No single feature explains the dominance of this gauge type. It is the combination of several engineering advantages that are difficult to beat as a package.
- Simple and reliable. A curved tube, a link, a gear sector, and a pointer. There are few parts that can wear out or break.
- Very wide pressure range. Bourdon tube instruments cover from about 0.6 bar up to several thousand bar, which suits the vast majority of industrial processes.
- No power required. Unlike sensors and transmitters, a mechanical gauge still shows the pressure during a power failure.
- Adequate accuracy. Standard classes of 1.6 or 1.0 cover most monitoring, alarm, and safety duties.
- Low manufacturing cost. Mature mass production keeps the purchase price far below electronic alternatives.
- Quick replacement. Standard dial sizes, thread types, and mounting forms mean a spare gauge can be installed within minutes.
This set of qualities is why the Bourdon tube gauge appears again and again in industry. If you are comparing it with diaphragm-style elements, our technical guide on Bourdon tube vs diaphragm pressure gauge selection can help you understand the crossover points.
How a Bourdon Tube Gauge Works
The sensing element is a curved or coiled tube with an oval cross-section. When pressure enters the tube, the cross-section becomes rounder, and the free end of the tube straightens slightly. A link and a gear sector amplify this small movement and turn a pointer on a calibrated scale.
- Pressurized fluid or gas enters the open end of the Bourdon tube.
- The tube deformation grows as the pressure rises.
- The connecting link transfers the movement to the gear sector.
- The pointer moves across the dial to show the measured value.
- When the pressure drops, the elastic tube returns the pointer toward zero.
Because the elastic element does the work, the material quality and heat treatment control repeatability. Brass and phosphor bronze are common for air, water, and oil. For corrosive media, a 316 stainless steel tube and welded socket are used. When pumps or compressors create vibration, the case is filled with glycerin or silicone oil to dampen pointer flutter and protect the movement.
Common Variations of the Bourdon Tube Gauge
Not every Bourdon tube gauge has the same shape. Manufacturers produce several tube geometries to cover different pressure levels and sensitivity requirements.
- C-shape tube: The most widespread variation. It is compact, simple to manufacture, and adequate for pressures from a few bar up to roughly 1000 bar.
- Spiral tube: The tube is wound into several turns, which increases the effective angular movement. Spiral tubes give better sensitivity in lower ranges.
- Helical tube: A long helical coil produces a large deflection and is often chosen for recording instruments and high-pressure systems.
In addition to the tube shape, the case style matters. Common dial sizes for industrial use are 63 mm, 100 mm, and 160 mm. Radial connection (lower mount) is typical for direct installation on a pipe or line; axial connection (back mount) is used on panels and control boards. For standard 60 mm industrial instruments, the Y-series offers a dependable and economical Bourdon tube option.
Y60 Series Bourdon Tube Pressure Gauge for Industrial UseA dependable 60 mm radial or axial pressure gauge suited for direct pipe or panel mounting. Its durable construction supports accurate monitoring of gases and liquids in pneumatic systems.View Product →
Other Pressure Gauge Types Commonly Found in the Field
A Bourdon tube gauge is the most common type, but it is not the only one. Other mechanical designs solve particular problems in low-pressure, corrosive, or hygienic processes. Knowing them prevents an expensive mismatch between the gauge and the application.
Typical range and preferred application of each common pressure gauge type.
| Gauge type |
Sensing element |
Typical pressure range |
Best suited for |
| Bourdon tube |
Curved metal tube |
0.6 to 1000+ bar |
General industrial, hydraulic, pneumatic, steam service |
| Diaphragm |
Corrugated metal diaphragm |
16 mbar to 40 bar |
Corrosive media, viscous fluids, slurries, hygienic processes |
| Capsule |
Two welded diaphragms |
2.5 to 600 mbar |
Very low gas pressure, draft measurement, air flow monitoring |
| Bellows |
Metal bellows element |
0.6 to 10 bar |
Low-pressure gas and steam, level indication |
| Digital electronic |
Pressure sensor and display |
Depends on sensor range |
High-accuracy reading, remote data, calibration tasks |
The chart below illustrates the typical pressure range coverage of the main mechanical types. The Bourdon tube gauge covers the widest portion of the industrial spectrum, which is one more reason for its dominant position.
Typical pressure range coverage by gauge type (illustrative)
Bourdon tube
0.6 – 1000+ bar
Diaphragm
16 mbar – 40 bar
Diaphragm gauges deserve special attention because they solve several problems that a Bourdon tube cannot. When the process medium is corrosive, contains solids, or may crystallize, a diaphragm element protects the measuring system. This type is widespread in food processing, pharmaceutical production, and water treatment lines where cleanliness and isolation are priorities.
Which Pressure Gauge Is Most Common in Each Industry
Although the Bourdon tube gauge is the overall winner, the balance shifts when you walk into a specific sector. The most common pressure gauge in one industry is usually a specialized variation chosen for the local conditions.
General manufacturing, hydraulics, and pneumatics
The standard copper-alloy Bourdon tube gauge appears on pumps, compressors, machine tools, and test benches. A 63 mm or 100 mm dial with a 1/4" BSP or NPT connection, selected so that the normal working pressure stays between 25% and 75% of the scale, is the typical solution.
Petrochemical and chemical processing
All-stainless steel Bourdon gauges and diaphragm gauges are the common choice. Wetted parts resist hydrochloric acid, hydrogen sulfide, and other aggressive chemicals. A PP or PTFE diaphragm seal prevents crystallization and clogging in polymerizing media.
HVAC and refrigeration
Refrigeration pressure gauges with a capillary tube allow remote mounting on a panel while the sensing element sits on the refrigerant line. In service kits, the most common instrument is a dual-scale gauge that shows both pressure and saturated temperature for refrigerants such as R134a, R22, or R410A.
Water treatment and filtration
Diaphragm-sealed gauges are common on water lines that carry suspended solids, while compact Bourdon gauges appear on filter housings and reverse osmosis manifolds. Brass internals are acceptable for potable water; seawater and chemical dosing lines need stainless steel wetted parts.
Medical equipment
Small precision gauges are used on anesthesia machines, ventilators, oxygen regulators, and vacuum systems. Accuracy and smooth response are more important than a wide range, and the wetted materials must be compatible with medical gases.
The selection logic starts with the same three questions in every industry: what is the process medium, what is the operating pressure, and what is the installation environment. As a manufacturer, we build gauges that cover all of these categories, and our engineers can recommend a specific model when the application is outside the standard range.
All-Stainless Steel Petrochemical Diaphragm Pressure GaugeBuilt with corrosion-resistant materials and a diaphragm seal, this gauge handles harsh media, high temperatures, vibration, and clogging risks, making it ideal for demanding petrochemical processes.View Product → 
HVAC Pressure Gauge Without CapillaryEliminates capillary connections to simplify installation, reduce maintenance, and improve vibration resistance. A reliable choice for HVAC systems where long-term stability and lower costs matter.View Product →
Practical Checklist for Selecting a Pressure Gauge
Selecting a pressure gauge becomes straightforward when the requirements are written down in a fixed order. Most field failures trace back to one skipped step, not to a mysterious product defect.
- Identify the process medium. Determine which parts of the gauge will contact the medium, then select the wetted material (brass, bronze, 316 stainless steel, PP, PTFE) accordingly.
- Define the maximum working pressure. Choose a full-scale range that is 1.5 to 2 times the normal working pressure so that the elastic element operates in a safe, repeatable region.
- State the accuracy requirement. Class 2.5 or 1.6 is common for monitoring; class 1.0 is used for test and calibration; 0.25 or better is the domain of digital instruments.
- Check the medium temperature. If the process temperature exceeds about 80°C, use a siphon, a cooling element, or a diaphragm seal to keep the gauge within its temperature limit.
- Assess vibration and pulsation. In pump discharge or compressor service, choose a liquid-filled gauge or add a pressure snubber to protect the movement.
- Confirm the process connection. Common threads are 1/4" NPT, 1/2" NPT, G1/4, G1/2, and M20×1.5. The thread type and size must match the process port exactly.
- Fix the mounting arrangement. Radial connection for direct mounting on a pipe, axial connection for panel mounting, and flange or bracket mounting where the gauge must sit flush on a panel.
- Select the dial size. A 63 mm case suits portable or OEM equipment; 100 mm and 160 mm cases improve readability and allow more accurate scale divisions.
Common Mistakes When Buying Pressure Gauges
Full-scale range too close to the working pressure
When the normal working pressure sits above 75% of the scale, the elastic element sees constant stress and loses accuracy faster. Leave headroom above the maximum expected value.
Wrong material for the medium
Brass and copper alloys are fine for air, oil, and clean water, but they are damaged quickly by acids, seawater, and ammonia. Check the compatibility table of the wetted parts before installation.
Bourdon gauge used for a low-pressure gas line
Below roughly 0.6 bar, a Bourdon tube responds poorly and the pointer is difficult to read accurately. A capsule or diaphragm gauge is a better match for low-pressure gas.
Dry gauge installed on a vibrating line
On pump discharge and compressor lines, a dry gauge can fail within weeks because of pointer flutter. A liquid-filled case or a snubber in the connection protects the gear movement.
Calibration and Maintenance Basics
Even a robust mechanical gauge needs attention in service. The usual recommendation is to check calibration every 6 to 12 months, depending on the duty and on how critical the reading is to plant safety. A gauge that does not return to zero, has a bent pointer, shows a scratched dial, or has a cracked lens should be taken out of service immediately.
During calibration, a deadweight tester or a calibrated reference gauge is used as the standard. Pressure is applied in five evenly spaced steps up to full scale and then back down. The difference between the reading and the reference value is compared with the allowed limit of the accuracy class. If the error is outside the limit, the gauge is adjusted or replaced.
Frequently Asked Questions
Is the Bourdon tube pressure gauge the most accurate gauge type?
No. Digital pressure gauges can reach 0.25% of full scale or better. However, the accuracy of a Bourdon tube gauge, typically class 1.0 to 2.5, is sufficient for most industrial monitoring and safety functions, and the lower cost and higher reliability explain why it remains the most common choice.
When should I choose a diaphragm pressure gauge instead of a Bourdon tube gauge?
Choose a diaphragm gauge when the medium is corrosive, viscous, contains solids, or has a pressure below about 0.6 bar. A diaphragm element also prevents the process fluid from entering the movement, which improves service life in dirty media.
Should I use a dry or liquid-filled pressure gauge?
Liquid-filled gauges use glycerin or silicone oil to dampen vibration and pulsation. For pumps, compressors, and vehicles, a liquid-filled gauge gives longer life. For steady, clean processes, a dry gauge is lighter and slightly easier to read from a distance.
What does accuracy class 1.6 mean on a gauge dial?
It means that the maximum error at any point on the scale is within plus or minus 1.6% of the full-scale value. For a 0 to 10 bar gauge, the displayed value can deviate from the true pressure by up to 0.16 bar.
How long can a Bourdon tube pressure gauge last?
In a clean, stable application with no overpressure events, a quality Bourdon tube gauge typically lasts several years to more than a decade. The limiting factors are temperature, vibration, corrosion, and pressure cycles rather than time alone.
When engineers ask what the most common pressure gauge is, the answer has not changed for more than a century. The Bourdon tube gauge is the standard instrument because it offers a useful combination of range, accuracy, cost, and durability. For unusual conditions, the diaphragm, capsule, bellows, and digital gauges covered in this guide step in and complete the pressure measurement picture.
We manufacture Bourdon tube gauges and specialized models for HVAC, petrochemical, water treatment, medical, and general industrial use. If you are not certain which type suits your process, send us the medium, the pressure range, and the installation details, and our engineering team will recommend a suitable model.
