What Does an 1800 Bar Pressure Rating Mean?

An 1800 bar pressure rating means equipment designed to contain pressure up to 1800 bar, which is about 26,107 psi or 180 MPa. One bar equals 100 kPa or roughly 14.5 psi, so 1800 bar is about 1,776 times standard atmospheric pressure.

What is a bar?

Bar is a metric unit of pressure defined as exactly 100,000 pascals, or 100 kPa. Standard atmospheric pressure at sea level is 1.01325 bar, so a bar is close to one atmosphere. Pressure gauges on hydraulic equipment are commonly read in bar, while psi (pounds per square inch) is common in the United States and in some aerospace documents. The SI unit of pressure is the pascal, and MPa is often used for high pressure: 1 MPa = 10 bar.

Bar to psi conversion

Use 1 bar = 14.5038 psi, or 1 psi = 0.0689476 bar. The table shows values common in hydraulic testing, rounded to the nearest psi.

bar	MPa	psi (approx.)
100	10	1,450
250	25	3,626
350	35	5,076
500	50	7,252
700	70	10,153
1000	100	14,504
1400	140	20,305
1800	180	26,107

Gauge and absolute pressure differ: bar(g) is measured relative to the surrounding atmosphere and bar(a) is measured relative to a vacuum, so 1 bar(g) is about 2.01 bar(a) at sea level. Test-bench pressures are normally quoted as gauge pressure.

What an 1800 bar rating means in practice

At 1800 bar, pressure alone is enough to deform or burst steel vessels that are not designed for it, so equipment at this level is built around heavy, high-strength pressure containment, high-pressure pumps or intensifiers, and guarded test enclosures.

A machine's rating is also not the same as the pressure it normally runs at. Test equipment is usually designed with a structural capacity above the pressures it applies in routine testing, and that margin is deliberate. The Neometrix bomb shell hydraulic pressure test bench page follows this pattern: it describes an operating range to approximately 1400 bar with structural capacity to 1800 bar, for proof-testing empty shell bodies. In psi terms, 1400 bar is about 20,305 psi and 1800 bar is about 26,107 psi.

Where these pressure ranges are used

Other Neometrix systems cover lower ranges: a hydraulic pressure test bench at 500 bar, a hydraulic proof pressure test rig at 700 bar and a 1000 bar proof pressure test bench at 1000 bar. Choosing a rating starts with the proof pressure the standard or drawing requires (see proof pressure testing) and adds margin. Neometrix builds custom hydraulic test benches for a wide range of pressures; the hydraulic test bench manufacturer page gives an overview.

Frequently asked questions

How many psi is 1800 bar?

About 26,107 psi (1800 x 14.5038).

How many MPa is 1800 bar?

180 MPa, because 1 MPa equals 10 bar.

How do you convert bar to psi?

Multiply the bar value by 14.5038. For a quick estimate, multiply by 14.5.

What is the difference between bar(g) and bar(a)?

Bar(g) is gauge pressure, measured relative to atmospheric pressure. Bar(a) is absolute pressure, measured relative to a vacuum; at sea level it is about 1.01 bar higher than the gauge reading.