Sampling non-homogeneous crude oil in static tank - by lowering flexible sampling tube into tank, closing tube end valve, removing tube, and squeezing out sample

摘要

The tube is of constant section and open at its ends, the valve in the lower end pref. being of the float type having a density near to that of the liq. being sampled to ensure that the tube is automatically blocked as the tube begins to be lifted out of the tank. Alternatively, a flexible tubular non-return valve or a valve operated remotely by a cable or wire pulled by a winding device, may be used to close the end of the tube when it is to be withdrawn from the tank. A wiping device may be provided to remove excess oil from the outside of the tube after removal from the tank, and squeezing of the tube is pref. accomplished by passing it through pressure rollers. The end of the tube can be connected to a wire by which it is pulled out of the tank and guided to a vessel for receiving the sample. The system is esp. applicable to petroleum products and crude oil stored in tanks, either on land, fixed or vehicular, or in tanker vessel at sea. The composition of the samples precisely reflects the composition of the oil at the position at which the sample was taken, however this may vary with depth, the appts. and its operation being simple.