| 摘要 |
<p>The method of contemporaneously sealing interfaces of bearing surfaces for valve faces and cylinder linings in a steel rotary cylindrical barrel having a plurality of longitudinal bores extending through the barrel longitudinally from one end to the other, each of the bores having a restricted diameter intermediate portion connecting a valve surface area at one end of the barrel with a cylinder area extending to the other end. An insert of bearing material is placed in both ends of the bore and a cap secured over a lower end adjoining the cylinder bore. A removeable carbon hot top is placed over the other end of the barrel. The barrel and its assembly is heated in a metalurical furnace for 90 minutes at 1925 °F, disposed vertically, with the cap at the bottom and is then removed from the furnace and cooled with the cap resting on a bronze pedestal to cause the bearing material to slowly solidify from the bottom up, and to cause gases to rise through the restricted area of the bore as the barrel cools. When the temperature is below 1000 °F, the hot top is removed to permit solidification of the bearing material in the upper valve area.</p><p>REFERENCE TO PRIOR CASES</p><p>This invention is related to U.S. prior patents Nos. 3109 488, 3 707 034, 3 707 035 and 3 709107, assigned to the same assignee as the present invention, these patents being for various methods of bonding bearing material in a steel bore. The Eldred Patent No. 1 217 581 is also relevant to the present invention. These patents are in part incorporated herein by reference for defining background material for the present invention.</p> |
