Tricorn, a maker of pipes for the power industry and aircraft engines, posted a sharp increase in half year pre-tax profit and is confident that full year results will be ahead of market expectations.Tricorn noted a continued recovery in Energy and Transportation businesses which helped lift pre-tax profit before exceptional items to £449,000 for the half year ended 30 September 2010 from £105,000 the year before. Revenue increased to £10.1m from £7m a year before. Net debt almost halved to 551 from 1,049 before. Chairman Nick Paul commented, "We are emerging from the contraction experienced in our key markets as a leaner more resilient business."Paul added that company made an encouraging start to the financial year. "We anticipate underlying demand levels to remain firm through the balance of the year."