The corrugations make the plates stiff so permitting the use of thin material. Corrugations also break up the liquid into small passages which tends to adhere to the metal and aid in efficient cooling. Turbulence as compared to smooth flow helps more of the liquid passing between the plates to come into contact with plate. The plate corrugations promote turbulence in the flow of both fluids and so encourage efficient heat transfer. A double seal arrangement is provided at each branch point with a drain hole to detect leakage and prevent intermixing or contamination. The plates have various designs of corrugations to aid heat transfer and also provide stiffness to the plates. Seals around the ports are so arranged that one fluid flows in alternate passages between plates and the second fluid in the alternative passages, usually in opposite directions. The inlet and outlet branches for each liquid are attached to one end plate. The plates, which are supported beneath and hung at the top by metal rails on which the plates can be moved, are held together against an end plate by clamping bolts or tie bolts. Each plate’s working space is protected by a nitrile rubber joint. Such plates have with horizontal or chevron pattern corrugations. Plate type Heat Exchangers are made up from an assembly of identical metal plates pressed together. FLOW PATTERNS USED IN PLATE TYPE COOLERS.

Plate type heat exchanger