Tons or Tons Force per Square Inch (UK, Long) is a very large pressure unit used historically for measuring extremely high pressures. 1 ton per square inch (UK, Long) equals 15,444,300 pascals.

This Imperial version of tons per square inch uses the United Kingdom long ton which is equal to 2,240 pounds (lbs).

Due to the high value of one tsi (uk, long) it is not used for common every day pressures and is mostly used when quoting pressures generated by geological forces or deep ocean depths. The tsi (uk, long) unit is also used as a measure of tensile strength of materials such as steel.

To convert one tfsi (uk, long) into other pressure units please see the table below.

For conversion to tfsi (uk, long) please click on the approriate unit below to obtain the value.

For multiple conversions to and from tsi (uk, long) use our online pressure calculator.

View the derivation of tsi (uk, long) from SI units and verify the identity of a tsi (uk, long) pressure unit.

## Conversion Factors

- 154.443 bar
- 2240 psi
- 154443 mbar
- 15444300 N/m²
- 15444300 Pa
- 154443 hPa
- 15444.3 kPa
- 15.4443 MPa
- 157.488 kg/cm²
- 1574880 mmH2O 4°C (39.2°F)
- 157488 cmH2O 4°C (39.2°F)
- 1574.88 mH2O 4°C (39.2°F)
- 62003.0 inH2O 4°C (39.2°F)
- 5166.92 ftH2O 4°C (39.2°F)
- 115841 mmHg 0°C (32°F)
- 11584.1 cmHg 0°C (32°F)
- 4560.69 inHg 0°C (32°F)
- 115841 Torr
- 115841000 mTorr
- 152.423 atm
- 157.488 at
- 154443000 dyn/cm²
- 35840 oz/in²
- 115841000 µHg 0°C (32°F)
- 1 tsi (uk, long)
- 1.12 tsi (usa, short)
- 161.280 tsf (usa, short)
- 322560 psf
- 157488 g/cm²

*Please note that the conversion factors above are accurate to 6 significant figures.*

## Derivation

The calculation below shows how the pressure unit Tons per Square Inch (UK, Long) (tsi) is derived from SI Units.

#### Formula

- Pressure = Force / Area
- Force = Mass x Acceleration
- Acceleration = Distance / (Time x Time)

#### SI Units

- Mass: kilogram (kg)
- Length: metre (m)
- Time: second (s)
- Force: newton (N)
- Pressure: pascal (Pa)

#### Input Values

- 1 Ton (uk, long) = 2240 lbs
- 1 Pound = 0.45359237 kg
- 1 Inch = 0.0254 m
- 1 Square Inch = 0.0254 m x 0.0254 m = 0.00064516 m²
- Acceleration = Standard Gravity = 9.80665 m/s²

#### Calculation

1 Ton Force (uk, long) = 2240 lbs x 0.45359237 kg x 9.80665 m/s² = 9964.016418 N

1 tsi (uk, long) Pressure = 9964.016418 N / 0.00064516 m² = 15444256.34 Pa

## Alternate Descriptions

These are the different versions used for identifying tsi (uk, long) that you may find elsewhere.

- Ton per Square Inch
- Ton Force per Square Inch
- Tons per Square Inch
- Tons Force per Square Inch
- tsi
- tfsi
- ton/in²
- tons/in²
- ton/in^2
- tons/in^2
- ton/sq in
- tons/sq in
- tonf/in²
- tonsf/in²
- tonf/in^2
- tonsf/in^2
- tonf/sq in
- tonsf/sq in

## Help

### 80 psi & 4.75″ dia air cylinder conversion to tons force

*I’m trying to work out tons force on a air cylinder with a pressure of 80 psi and a diameter of 4.75 inches. This is how I was working out the force:*

*4.75/2= 2.375*

* 2.375 x 2.375 x 3.142 = 17.7228 sq inches*

* 17.7228 / 2240 pounds = 0.0079*

* 0.0079 x 80 psi = 0.6329 ton*

*Just need to make sure my formula is right?*

Yes your formula is correct. You could use these tools to verify your pressure & area to force and circle diameter to area calculations.