Fig. 36 shows a flange coupling such as would be used to connect up a line shaft in a shop, or any heavy machinery shafting. The detail construction of this is most clearly shown by making the drawing in cross section. This drawing is a good illustration of the placing of the dimensions entirely outside the lines of the drawing, thus enabling any changes to be made in the figures without in any way obliterating the drawing. It also keeps both drawing and figures definite and clear, avoiding any possibility of confusion. Each half of the coupling is fastened to its shaft by a tapered key; and in order that it may be clearly understood which way the top of the keyway is tapered, the arrows, shown in the cross-sectional view, indicate the direction in which the key is driven home.
On this drawing are indicated the pattern numbers. They would be equally necessary on all other castings illustrated in this book; but for purposes of simplicity they have generally been omitted. Pattern numbers are necessary, not only that the patterns may be filed away systematically, and readily found when wanted, but also that the necessary orders for the castings may be written, and that the pieces may be identified on the drawings. For wrought-iron and steel pieces which have no patterns, certain letters or numbers are given them, such that the identification is as complete as with castings. Castings, whenever possible, carry on their surface the pattern numbers in raised figures, and when received in the shop or field can thus be identified for assembling in the machine. Wrought-iron and steel pieces, which cannot have such figures raised upon them, are usually marked with painted letters and figures, to correspond with piece marks called for on the drawing, thus enabling them to be properly identified at the shop and in the field. There are many different systems in vogue for this numbering, dependent upon the particular requirements of the shop organization to which it applies.
2 1/2 flange Coupling - Steel Casting.
2 - Female- MSC 6 Ship with Shaft MS17 2 - Male - MSC 5 . . . . MS18.
Fig. 36. Detail Drawing of a Coupling, Using a Cross-Sectional View.