WHAT TO LOOK FOR WHEN CHOOSING A FUEL PUMP
In today’s fast paced digital world, it can be a little bit hard at times to go through all the options available to you and find the item you’re looking for. When it comes to pumping fuel, the vast amount of options is almost daunting.
There are three main questions to ask when choosing a fuel pump system that is suitable for your needs:
How fast do you want to refuel your vehicles?
How accurately do you want to measure the fuel you use?
Where is your fuel storage tank?
Let’s cover each question in turn.
You will want to refuel your vehicles as quickly as possible – this is a given. No one wants to fill up slowly. However, if the fuel pump dispenses at too fast a speed it can create splashback and excessive frothing in the vessel being filled, causing spillage, wasted fuel and the possibility of excessive frothing.
If you are using an automatic shut off nozzle, the froth produced from too high a flow can trip your nozzle sensor. This means drivers have to repeatedly wait for the froth to settle & then top up the tank, thereby slowing down the refuelling process.
The three main flow breaks are listed below.
Low speed, 40 litres per minute – Suited for Cars, light vans, forklifts, jerry cans and small plant equipment.
Medium speed, 60 litres per minute – Suited for Large vans, small rigid trucks, agricultural vehicles and large industrial plant equipment. High speed, 80 litres per minute – Ideal for filling vehicles with large capacity fuel tanks such as buses & coaches, articulated vehicles, heavy plant equipment and quarry/mining equipment
This is a crucial question if you wish to keep track of your fuel usage. Higher accuracy metering will cost more but if you are using any significant quantity of fuel you may quickly recover the extra cost. Lower accuracy, lower cost metering should ideally suit the smaller fleet. There are two basic types of meter in most fuel pumps sets, detailed below.
Nutating Disc Meters.
- Approximate accuracy of +/- 2%
- Accuracy varies with delivery speed and fuel type
- Should be calibrated after installation and regularly checked
- If topping up tanks to the brim, the accuracy will be lowered further
Oval Gear Meters.
- Accuracy of +/- 0.5%
- The actual accuracy will be constant at different delivery speeds, so topping tanks up to the brim will not cause a problem
- Check calibration after installation but only re-check annually unless you have a particularly high fuel usage
So, one is more accurate than the other, so what?
The accuracy percentage is how closely the fuel figure shown on the pump matches the quantity of fuel actually drawn. As you can understand, if you dispense more or less than is shown on your meter, records will be inaccurate.
Example of a +/-2% pump If a driver fills a vehicle with fuel until 100 litres is shown on the pump display then it means he actually delivered anything between 98 & 102 litres (100 litres +/- 2%) This gives an uncertainty of 4 litres, not including all other factors present at the time that could affect meter accuracy.
Example of a +/- 0.5% pump If a driver fills a vehicle with fuel until 100 litres is shown on the pump display then it means that he actually took between 99.5 & 100.5 litres (100 litres +/- 0.5%) This gives an uncertainty of 1 litre, 4 times better than the +/- 2% pump.
The same theory applies to your overall fuel usage. If the total of all your individual refuelling adds up to 10,000 litres in a month then you actually used between 9,800 & 10,200 litres if you have a +/- 2% accuracy pump. This is an uncertainty of 400 litres a month! Being uncertain about that much fuel could cost a lot of money.
All key and card operated fuel monitoring systems connect to the output of the meter in the fuel pump. This means that the figures produced by your fuel monitoring system can only ever be as accurate as the meter it is connected to. If you have a worn, old or inaccurate fuel meter don’t expect your fuel monitoring figures to be any better!
WHERE IS YOUR FUEL STORAGE TANK?
If your tank is below ground you will need a pump with enough suction strength to pull from the tank, depending on how deep it is. If your tank is above ground, less suction lift is necessary but you need to be careful that the installation is protected against leakage in the event of damage to the dispensing equipment. The pump you decide to install will only work correctly if properly connected to the storage tank. A high flow pump won’t deliver at its intended flow rate if a suction that is too small is fitted. It is always best to check the pump specifications and how well it will match the system you are trying to fit it in to. There is no point purchasing a pump with a two meter suction lift if your system requires a four meter suction.
If you have any doubt about your installation or want advice on what will best suit your operation, the sales team at Equipco can offer you advice for the best system to suit you.
April 26, 2016 | View: 1020