BATH — Shipyard workers angry over efforts by Bath Iron Works to require them to work outside their specialties and to hire subcontractors for some items marched down Washington Avenue on Thursday.

Some of the 1,000-plus demonstrators shouted “Go home, Fred,” a reference to BIW President Fred Harris, who says he is trying to make the shipyard more efficient.

Harris wants to update job classifications and wants some items like hatches and lockers made elsewhere to save money.

He says the shipyard must adopt the changes if it expects to win a contract for Coast Guard cutters.

Union President Jay Wadley put the number of demonstrators at more than 1,500. The workers left their jobs on their lunch break and quickly returned to work after marching to the union hall.

“It’s a sign of solidarity. The company has done something that we don’t agree with. We anticipate a long, hard road,” he said.

Local S6 is going to arbitration over the company’s efforts to have items built elsewhere. The union is also suing to stop the company from going to arbitration May 29 over efforts to reclassify workers to perform multiple tasks.