. American foundry practice . forms of castings that they maybe called upon to cast, at least all that are large and of dif-ferent proportions; also, during this months experiments,make test bars of all the different grades of iron that areused in the foundry, and after making note of their con-traction then trytheir tensile or break-ing strain, somethingwould be learned. Todo all this requires nogreat labor or that take aninterest in their tradecould, whenever theymake a casting of anynote, test the contrac-tion and keep a recordof experiments thatwould be valuable. The moulder
. American foundry practice . forms of castings that they maybe called upon to cast, at least all that are large and of dif-ferent proportions; also, during this months experiments,make test bars of all the different grades of iron that areused in the foundry, and after making note of their con-traction then trytheir tensile or break-ing strain, somethingwould be learned. Todo all this requires nogreat labor or that take aninterest in their tradecould, whenever theymake a casting of anynote, test the contrac-tion and keep a recordof experiments thatwould be valuable. The moulder or pat-tern maker is not al-ways responsible forthe breaking or crack-ing of a casting. Thedesigner or draughts-man often designsforms that the bestof iron and manage-ment would not pre-vent from cracking. Sometimes castings will stand in theshop for weeks, and even months, and, to the surprise of all,will then crack. Not long since I had occasion to cast a bar 4 X 9, and14 feet long. With the same ladle of iron I cast a test. •;• ? o
Size: 1483px × 1684px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublish, bookpublisheretcetc
