Understanding Litres per minute to Imperial Gallons per Hour Conversion
Both litres per minute (l/min) and imperial gallons per hour (imp-gal/h) express volume flow rate — how much fluid moves past a point per unit of time. A litre per minute measures one litre passing a point each minute, while an imperial gallon per hour measures an imperial (UK) gallon of 4.54609 litres. This conversion comes up in plumbing, irrigation, pump sizing, HVAC and fluid-engineering work where flow specs are quoted in different unit systems.
Conversion Formula
To convert litres per minute to imperial gallons per hour, multiply by the fixed factor below:
So the rule is simply: imp-gal/h = l/min × 13.198154897945. To go the other way, multiply by .
Step-by-Step Example
Convert 22 l/min to imp-gal/h.
Write the formula, substitute the value, then calculate:
So 22 l/min equals imp-gal/h.
How to Convert Litres per minute to Imperial Gallons per Hour
Converting litres per minute to imperial gallons per hour takes one multiplication using the fixed factor. Here is the process with 22 l/min as a worked example.
- Write the conversion factor. One litre per minute equals a fixed number of imperial gallons per hour:
- Set up the multiplication. Multiply your flow value by that factor:
- Cancel the units. The l/min units cancel, leaving the result in imp-gal/h:
- State the result. Complete the arithmetic:
So 22 l/min = imp-gal/h.
Litres per minute to Imperial Gallons per Hour conversion table
| Litres per minute (l/min) | Imperial Gallons per Hour (imp-gal/h) |
|---|---|
| 0 | 0 |
| 1 | 13.19815 |
| 2 | 26.39631 |
| 3 | 39.59446 |
| 4 | 52.79262 |
| 5 | 65.99077 |
| 6 | 79.18893 |
| 7 | 92.38708 |
| 8 | 105.5852 |
| 9 | 118.7834 |
| 10 | 131.9815 |
| 15 | 197.9723 |
| 20 | 263.9631 |
| 25 | 329.9539 |
| 30 | 395.9446 |
| 40 | 527.9262 |
| 50 | 659.9077 |
| 60 | 791.8893 |
| 70 | 923.8708 |
| 80 | 1055.852 |
| 90 | 1187.834 |
| 100 | 1319.815 |
| 150 | 1979.723 |
| 200 | 2639.631 |
| 250 | 3299.539 |
| 300 | 3959.446 |
| 400 | 5279.262 |
| 500 | 6599.077 |
| 600 | 7918.893 |
| 700 | 9238.708 |
| 800 | 10558.52 |
| 900 | 11878.34 |
| 1000 | 13198.15 |
| 2000 | 26396.31 |
| 3000 | 39594.46 |
| 4000 | 52792.62 |
| 5000 | 65990.77 |
| 10000 | 131981.5 |
| 25000 | 329953.9 |
| 50000 | 659907.7 |
| 100000 | 1319815 |
| 250000 | 3299539 |
| 500000 | 6599077 |
| 1000000 | 13198150 |
What is Litres per minute?
Litres per minute (LPM) is a unit of volumetric flow rate, measuring the volume of liquid or gas that passes through a specific point in one minute. It is commonly used in various fields to quantify the rate of fluid transfer.
Understanding Litres per Minute (LPM)
LPM expresses how many litres of a substance flow through a given area in one minute. A litre is a unit of volume defined as 0.001 cubic meters, or 1000 cubic centimetres. Therefore, 1 LPM is equivalent to 1/1000 of a cubic meter per minute.
How is Litres per Minute Formed?
LPM is derived from the base units of volume (litres) and time (minutes). The formula to calculate flow rate in litres per minute is:
For example, if 50 litres of water flow out of a tap in one minute, the flow rate is 50 LPM.
Common Conversions
Here's a table of conversions between LPM and other common flow rate units:
| Unit | Conversion to LPM |
|---|---|
| 1 Cubic Meter/Hour | ≈ 16.67 LPM |
| 1 Gallon/Minute (GPM) | ≈ 3.785 LPM |
| 1 Millilitre/Minute (mL/min) | = 0.001 LPM |
Real-World Applications and Examples
-
Medical Oxygen Delivery: Oxygen concentrators and ventilators often specify flow rates in LPM. A typical oxygen concentrator might deliver oxygen at a rate of 2-5 LPM.
-
Water Flow in a Household: The flow rate of water from a tap or showerhead is often measured in LPM. For instance, a water-saving showerhead might have a flow rate of 7-10 LPM.
-
Aquarium Filters: The performance of aquarium filters is often rated in LPM, indicating how quickly the filter can process the aquarium water. An aquarium filter might have a flow rate of 500 LPM.
-
HVAC Systems: Airflow in HVAC (Heating, Ventilation, and Air Conditioning) systems is sometimes specified in LPM, especially in smaller systems or components.
-
Industrial Processes: Many industrial processes involving fluids, such as chemical mixing or cooling, use LPM to measure and control flow rates.
Interesting Facts
While there isn't a specific "law" named after LPM, the principles of fluid dynamics and flow rate are governed by laws such as the Hagen-Poiseuille equation, which relates flow rate to pressure, viscosity, and dimensions of the pipe.
The measurement of flow rate has been crucial in the development of various technologies and industries, from water management to chemical engineering. The accurate measurement of flow is essential for efficiency, safety, and control in many processes. For more information on this, read the Fluid dynamics article from sciencelearn.org.nz.
What is the Imperial Gallon per Hour?
The imperial gallon per hour (imp-gal/h) is a unit of volumetric flow rate expressing how many imperial gallons of fluid pass a point in one hour. It is used in the UK and other Commonwealth countries for pumps, fuel consumption, and plumbing flow ratings.
Definition
One imperial gallon per hour equals one imperial gallon of volume divided by one hour (3,600 seconds):
The imperial gallon is defined as exactly 4.54609 litres, so dividing by 3,600 seconds gives 4.54609 / 3600 = 0.00126280 L/s (equivalently 4.54609 L/h).
Origin and History
The imperial gallon was established by the British Weights and Measures Act of 1824, originally defined as the volume of 10 pounds of water at a specified temperature. It was later fixed by reference to the litre. The "per hour" rate arose naturally in the 19th and 20th centuries as a practical measure for pump throughput and fuel usage, hours being a convenient interval for slow, steady flows.
Law and Notable Facts
The imperial gallon (4.54609 L exactly) is legally distinct from and about 20% larger than the US liquid gallon of 3.785411784 L. As a result an imperial gallon per hour is likewise about 20% greater than a US gallon per hour. Since UK metrication, the imperial gallon is no longer a primary trade unit but persists in fuel-economy figures (miles per gallon) and equipment specifications.
Real-World Examples and Conversions
- A small garden or aquarium pump rated at 100 imp-gal/h moves about 454.6 litres of water every hour, roughly 0.126 L/s.
- A domestic tap running at 1 imperial gallon per hour is a bare trickle of about 4.55 L each hour.
- 1 imp-gal/h ≈ 0.833 US gal/h, reflecting the larger imperial gallon.
- A pump moving 220 imp-gal/h delivers about 1,000 L/h, or roughly 0.278 L/s.
Frequently Asked Questions
What is the formula to convert litres per minute to imperial gallons per hour?
Multiply the flow in l/min by the conversion factor 13.198154897945. In symbols, . This single-step multiplication works for any value.
How many imperial gallons per hour are in 1 litre per minute?
There are imperial gallons per hour in one litre per minute. Equivalently, one imperial gallon per hour equals litres per minute.
How do I convert 22 l/min to imp-gal/h?
Multiply: imp-gal/h. So 22 l/min is about imp-gal/h.
Where is the litres per minute to imperial gallons per hour conversion used in practice?
It shows up whenever a pump, meter, or system rates flow in one unit but a spec sheet, code, or supplier uses the other — for example matching an irrigation controller, a fuel-transfer pump, or an HVAC water loop to its rated imp-gal/h figure.
Is the litres per minute to imperial gallons per hour factor exact?
The imperial gallon is defined as exactly 4.54609 litres, so the conversion factor 13.198154897945 is exact up to the digits shown here; any small rounding only appears in the final displayed result.