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Foot valve opens top valve, too
Page 56
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A VACUUM-BREAKING foot valve has been developed for road tankers by a recently formed company trading under the name of Precision Transport Equipment Ltd., Fresh Wharf, flighbridge Road, Barking, Essex.
It is based on the hydraulic or mechanically operated units formerly made by the Torridon Steel tank-building company and it incorporates a positive opening valve situated in the top of the tank shell allowing a free passage for air to enter the vessel when contents are being offloaded.
Tests have shown that the valve permits a 16.7 per cent greater flow of water to pass through a Sin, valve than when the conventional vacuum valve in the lid is the only available entry.
The unit enables the vehicle to be operated with the fill-lids locked and completely eliminates the possibility of a collapsed tank. It is available either top or bottom operated and is guaranteed to contain the cargo in event of the vehicle overturning.