tender for competitive e-bidding for rate contract for supply of brass tubes and conversion of old brass tubes into new brass tubes for various co-operative and corporation sugar mills in uttarakhand in the year 2026-27 , new seamless solid drawn 70:30 alloy brass tubes heat treated and guaranteed against dezincification and season cracking, tested to 1000 psi with ends suitable for expansion in tube plate, conforming to is:407-81, alloy-1, with test certificate. annealed condition having tolerance as per is: 5493/81 , size upto 2 dia , size above 2 dia , supply of new brass tubes (specifications same as mentioned above at s.no.1) on conversion basis , size upto 2 dia , size above 2 dia , current price of copper (cu) , current price of zinc (zn)