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

They were constructed under a guarantee for tightness, and after erection were tested by filling with water. Each is fitted with a 4-inch emptying and a 6-inch filling-pipe, with screw-valves, and furnished with a joint so that the orifice of each can be lifted up clear to the crown of the tanks by a hauling chain which passes over rollers at the top, and is brought down to the level of the ground outside, where it is worked by a small winding-gear.

The orifices can thus be maintained at about the surface of the oil so as to avoid the possibility of drawing off any water that may have accidentally got into the tank, and which being heavier than oil would sink to the bottom, and also the vibration and ebullition which would occur in filling against a head of pressure.

Each tank is provided with an external glass gauge from top to bottom, in lengths of about 4 feet, fitted with brass cocks, and each tube overlapping the other so as to show the height of the oil in the tank. A light iron ladder on the outside gives access to the roof, and another is fixed from one of the man-holes to the bottom inside.

The contract was given to Messrs. Lysaght & Co. of Bristol, and the cost was about £4,000. The tanks are painted preferably white outside, and are provided with a ventilator at the top.

The operation of filling is as follows:-

When a petroleum vessel arrives in port she is moored at the proper berth ; her petroleum-pumps are then connected with the pipe on the quay, the valve of any particular tank required to be filled is opened, and the pumping commenced.

As soon as the oil has been pumped out of the ship the valve at the stand-pipe is closed. At this stage of the proceedings the whole line of the feed-pipe from the quay to the storage tank will be full of oil.

To facilitate the extraction of this the feed-pipe has a slight fall at each end to a point near the filling-house, where a small Worthington pump is attached, and the contents of the pipe are transferred into a small tank in the filling-house.