Engineering solutions provider Weir Group said it expects full year pre-tax profit to be around £20m ahead of its previous expectations following a strong first quarter.Glasgow-based Weir Group said a record opening order book and contributions from acquisitions made last year has increased its confidence in achieving further good progress in 2011."First quarter performance was strong with the Group benefiting from a record opening orderbook, a positive contribution from the 2010 acquisitions and significant input growth, including record quarterly orders for the Minerals and Oil & Gas divisions," the group said in a company statement.Weir said strong revenue growth was also achieved in the quarter driven by both organic growth and contributions from the acquisitions made in 2010. Operating profits are up on the prior year period and operating margins are in line with our expectations.Order input was up 39% against the prior year period on a reported basis and advanced 30% on a like for like basis. Original equipment orders were up 49% while aftermarket orders rose 31% and up 22% like for like.CJ