N.A.T.O. The defensive military alliance formed in 1949 by ten european countries. WARSAW PACT A military alliance formed in 1955 by the Soviet Union Netherlands. Norway.
Tank Rings. Tank rings filled with gravel lift the tank above the surrounding grade. This keeps the tank out of standing water and increases the life of the tank bottom.
The 2:1 elliptical tank heads are used extensively for liquefied petroleum gas tanks, air receivers and other pressure vessels. For this type of head, the depth of tank head is one-quarter of the vesselâs internal diameter. With its reduced metal thickness, elliptical tank heads offer an economic solution for medium-pressure tanks. These can be formed from: