Hourly workers striking against LyondellBasell Industries NV’s (LYB.N) Houston refinery voted on Thursday to ratify a new four-year contract, clearing a key hurdle on the way to ending a three-month-long strike, according to a union official. No date has been set for the more than 400 members of United Steelworkers’ Local 13-227 to return to work as an agreement for re-entering the refinery has not been made with Lyondell, said Kent Farr, a committeeman with the local.