Lesson 7 Starting Air System报告.doc

Lesson 7 Starting Air System 第7 课 起动空气系统 1. Diesel engines are started by supplying compressed air into the cylinders in the appropriate sequence for the required direction. A supply of compressed air is stored in air reservoirs or bottles or receivers at pressures about 30 or 40 bar ready for immediate use. Up to 12 starts are possible with the stored quantity of compressed air. The starting air system usually has interlocks to prevent starting if anything is not in order 柴油机是按所需方向, 以适当顺序向各缸通入压缩空气起动的。所供压缩空气以30~40bar 的压力存于气罐或气瓶内, 随时可用。所储存的压缩空气量可进行多达12 次的起动。起动空气系统通常装有连锁装置, 若其他设备没准备好, 则不允许柴油机起动。 2. Compressed air is supplied by air compressors to the air receivers. The compressed air is then supplied by a large bore pipe to a remote operating non-return or automatic valve and then to the cylinder air start valve. Opening of the cylinder air start valve will admit compressed air into the cylinder. The opening of the cylinder valve and the remote operating valve is controlled by a pilot air system. Each cylinder air start valve is opened when the piston is just past TDC and closed just before the exhaust valve opens. There is always more than one air start valve open, which ensures that the engine will start in any position. 压缩空气由空压机提供给空气瓶。压缩空气通过大口径管道进入遥控操作的止回阀或自动阀, 进而到达气缸起动阀。气缸起动阀开启, 空气进入气缸。气缸起动阀及自动遥控阀由控制空气系统控制。每个气缸起动阀在(活塞)经过上止点后立即开启, 在排气口适当开启前关闭。通常至少有一个及以上的空气启动阀处于开启状态, 来确保主机能够在任何位置进行启动。 3. The pilot air is drawn from the large pipe and passes to a pilot air control valve which s operated by the engine air start lever. When the air start lever is operated, a supply of pilot air enables the remote valve to open. Pilot air for the appropriate direction of operation is also supplied to an air distributor. This device is usually driven by the engine camshaft and supplies pilot air to the control cylinders of the cylinder air start valves. The pilot air is then supplied in the appropriate sequence for the direction of operation required. The cylinder air start valves are he