8.11 The slabs then go on to a plate rolling mill and a milling machine which reduce them to finished flat plate roughly 1 meter x 1 meter. The blooms go through a billet rolling mill and a light section mill which produces small round and square stock. The round stock is made into nuts and fasteners while the square is milled to the required major and minor stiffeners. Note: Due to time restrictions on the study effort, the development of the construction scheme had to be based on preliminary specifications for the hull structure. Later refinements in structural analysis confirmed the assumed sizes for the hull and bulkhead plates. However, major and minor stiffeners and the fasteners described in Section VII.5.3 are slightly larger than those assumed in this chapter. This variation does not affect ~he mass of the larger machinery whose maximum output could easily handle the increase in size. But it alters the power requirement for stiffener and fastener manufacture, and increases the mass of the light machine tools involved in these operations. Fortunately, the machinery masses and power consumptions for stiffener and fastener manufacture are small fractions of the total equipment mass and power requirement, and the size alterations would thus add only minor corrections to these totals. The equipment necessary for manufacture falls into two categories: heavy rolling mills and shears, and lighter machine tools. Each of the individual pieces of equipment will be discussed next. VIII.4.3: Rolling Mills and Related Equipment VIII.4.3.1: General Design and Function: A rolling mill is a large machine tool which uses pressure exerted through rollers to reduce the size of a piece of metal, usually hot. A complete rolling mill consists of: the basic equipment including the rollers, a stand to house the rollers, and the mechanisms transmitting the rotation to the rollers; the electrical equipment to power the mill; the lubrication system; and the auxiliary equipment, including shears to crop and cut up the rolled piece and equipment to transport and handle the rolled pieces. Because of their nature, rolling mills are very large, heavy machines. The masses, power requirements, and productivity of the
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