Shares in engineering solutions provider Tata Group company Voltas Ltd rose nearly 20 percent after December quarter operating profit rose 6 percent,despite the company reporting a net loss of 1.15 billion rupees,dealers said. Build up of fresh long position in futures and options segment also aided gains,they said. Voltas said losses were due to an 'onerous' contract worth 2.77 billion rupees in Qatar which escalated costs. At 11.41 a.m.,shares were up 18.5 percent at 112.05 rupees. Stocks More on Voltas Company INFO More on Voltas