Stop sales from the tank and let the fuel settle. Lower the clean dip rod straight down the dip pipe until it touches the bottom, lift it out at once, and read the wet line at eye level. Take a second reading; if the two differ, take a third. Then convert the dip to litres with the tank's chart.
Before you dip
- Stop sales from that tank. A pump drawing fuel makes the surface move.
- Wait a few minutes after the last sale, longer after a tanker: 10 to 15 minutes for the surface to settle.
- Wipe the rod clean and dry from end to end.
Taking the dip
- Open the dip pipe cap.
- Lower the rod slowly and straight down the dip pipe until it just touches the bottom. Do not let it drop or bounce.
- Hold it there for a second, then lift it straight out.
- Read the top of the wet line at eye level. On a dull day, a little product-finding paste on the rod makes the line sharp.
- Wipe the rod and dip again. If the two readings differ by more than a millimetre or two, take a third and use the two that agree.
- Close the cap.
Check for water
The MDG asks for a water dip every day as part of the daily stock register. Smear water-finding paste on the bottom few centimetres of the rod and dip again. Where water touches it, the paste changes colour. Read that line. See water in the tank.
Turn the dip into litres
Use your tank’s calibration chart, or the dip to litres calculator. Type the water dip too and the water is taken off.
If your rod marks centimetres with four 2 mm bars, write the reading as centimetres and bars and convert it properly: 58 cm and 4 bars is 58.8 cm, not 58.4. See reading a dip rod.
Write it down
Clause 1.3 of the MDG asks for a daily record of product and water dips of each tank, taken in the morning, with the pump meter readings. The Dip Density app keeps every dip with its time and the litres.
Figures here are for reference. Your oil company’s certified calibration chart, approved instruments and the Marketing Discipline Guidelines always prevail.
Questions
When should I dip?
Every morning before sales, for the daily stock register, with a water dip at the same time. Before and after every tanker. And whenever the stock looks wrong.
Why does the reading change if I dip twice?
Fuel climbs a wet rod, the surface ripples if a pump has just run, and a rod lowered at an angle reads high. Wipe the rod, wait, and lower it straight.
How much does one millimetre matter?
In a 20 KL tank near half full, one centimetre is 125 to 135 litres, so one millimetre is about 13 litres. At the bottom or top of the tank it is far less.