Volume Twelve - Pre-Victorian to the Present Day - further aspects - Petroleum-Storage Installations at Avonmouth and at Cardiff [1890] . . . .

As it may sometimes be necessary for repairs to take the oil out of one storage tank and put it into another, a branch D is laid from the 6-inch filling pipe No. 1 to C, and the transfer of oil from one tank to another takes place by gravitation from the tank through the 4-inch emptying pipe No. 2, along B, to the pump, and thence along C and D into pipe No. 1 passing on to the other tank, as if it was being pumped from a vessel ; in this case valves g and ƒ are opened and valves a, b, c, d, e, h and i are closed.

It will be seen that this arrangement of pipes gives the foreman at the filling-house complete control over the direction taken.

A Worthington pump is used with a cylinder 8 inches in diameter and about 10 inches stroke.

A little above the floor-level, and running the entire length of the barreling tanks, two iron waste-troughs are fixed.

The process of barreling is as follows : -

Empties are rolled up off the long platform into the filling-house and put on these troughs close together, as shown in Figs. 16 and 18, with the nozzles from the tanks dipping into the bung holes. When filled they are rolled down the barrel-run to the jetty, or if required to go away by rail, to the siding.

To prevent barrels from being overfilled, an American automatic filler, ingeniously arranged with a pneumatic sliding piston and spring shut-off, which can be so set as to regulate the speed of filling, is attached to the nozzles of the tank by a flexible tube. The pneumatic piston rises with the oil, and when the barrel is filled, the spring shut-off is released and the supply stopped.

The tank steamers for conveying petroleum to England range from 2,000 up to 4,000 tons carrying capacity. The engines and boilers are usually aft, the petroleum hold occupying almost the whole of the remaining portion of the ship.