tender for purchase of calandria of evaporator heating surface 440 m2. , manufacturing, supply, erection and commissioning without tubes and dismantling of complete milded steel calandria for 3rd evaporator body including dismantling of existing calandria as per following details : - ( 1 ) heating surface : 440 m2 ( 2 ) wall or calandria shell thickness : 12 mm ( 3 ) thickness of lower and upper tube plate : 25 mm ( 4 ) dia. of down take : 6”inch. ( 5 ) thickness of down takepipe : 12 mm ( 6 ) i.d. hole for down take : 500 mm ( in upper tube plate ) ( 7 ) dia of calandria / tube plate : 2772 mm ( 8 ) size of tubes : o.d. = 45 mm, i.d. = 42 mm, length = 2010 mm long. efficient distribution of steam should exist in calandria alongwith arrangement of vapour pipe connection at proper place. proper light and heavy non condensate gas removal system should be there and folding three flange type non condensable gases system should be accepted. suitable arrangement of down take should be there in calandria non condensate pipes and all material to it upto connection in the main header of non condesate removal will be in scope of supplier calandria shell be exceed 150 mm.