Dwindling orders for steam generators caused Babcock & Wilcox Canada to lay off another 50 people at its Cambridge plant Tuesday.The Waterloo Record reported that the jobs belonged to salaried technical and administrative workers in B&W's manufacturing unit. In a release quoted by the paper, the company said its service business remains strong but its manufacturing sector has been hurt by weakened demand for large nuclear components. B&W Canada has dismissed 166 Cambridge workers since December. At that point, the plant southwest of Toronto laid off about 30 percent of its unionized workforce.B&W, headquartered in Charlotte, N.C., produces some of the world's largest boilers and steam generators at its Canadian plant. Among its orders recently delayed or cancelled, the Canadian plant had been selected in 2010 to provide two steam generators for completion of the Tennessee Valley Authority's Bellefonte unit 1 reactor. TVA recently announced it would reassess that project.