Shares in Siam Cement Pcl, Thailand's top industrial conglomerate, gained as much as 2.4 percent on expectations of good second-quarter earnings that would include a gain from insurance claims for flood damages.

Siam Cement reported on Wednesday that its first-quarter earnings fell by one-third due to a weak petrochemical margin, but said it expected a recovery in petrochemical business in the second quarter.

Out of 18 analysts tracking the company, 15 have a "buy" or "strong buy" rating, two rate it as a "hold" and only one has a "sell" rating.

"We anticipate the trough cycle in chemical spread to end this year and continuously improve from 2013 onward as we can see a pickup in global demand for chemical products, particularly from the automotive sector, and strong additional HDPE demand, which helps outstrip additional supply during 2012-16," said broker KGI Securities.

Siam Cement shares were up 1.8 percent at 340 baht. KGI set the stock's target price at 450 baht.

(Reporting by Viparat Jantraprap in Bangkok; viparat.jantraprapaweth@thomsonreuters.com; Editing by Chris Gallagher)