轴封装置

旋转轴和固定壳体之间的密封称为轴封。其作用是防止液体从泵内泄漏到外面，或当泵内压力低于大气压时，防止空气漏入泵中。尽管轴封装置所占的位置不大，但对机器的正常运转十分重要,是最容易发生故障的零部件之一。最常用的轴封装置是填料密封、机械密封和浮动密封。设计密封装置的要求是密封可靠，能长期运转，消耗功率小及适应泵运转状态的变

化，还要考虑到液体的性能、温度和压力。

1. 填料密封

图1-64为应用最广泛的软填料密封,又称为盘根盒密封,它用油浸石墨的石棉绳做填料,放在盘根盒(填料箱)中，由套筒和压盖压紧，依靠填料的变形达到密封。用软填料时，在填料层中间安装一个液封环，把高压液流引入此处,不仅能起密封作用，同时也能起润滑和冷却作用。为了避免工作时填料与泵轴摩擦过于剧烈.填料的压紧度不宜太大。
    填料的种类很多，除了石棉外，其基础材料还可以是金属合成橡胶、合成树脂和皮革棚麻，渣浆泵厂家以及适于高低温有腐蚀介质的柔性石棉填料和适于高速高压的碳素纤维筑料等，

Shaft seal device

The seal between the rotating shaft and the fixed housing is called the shaft seal. Its function is to prevent liquid leakage from the pump to the outside, or when the pressure in the pump is lower than atmospheric pressure, to prevent air leakage into the pump. Although the position of the shaft seal device is not large, it is very important for the normal operation of the machine, and it is one of the most prone parts to failure. The most commonly used shaft seal devices are packing seal, mechanical seal and floating seal. The requirements of the design of the sealing device are reliable sealing, long-term operation, low power consumption and adaptation to the change of pump operation state

In addition, the performance, temperature and pressure of the liquid should be considered.

1. Packing seal

Fig. 1-64 is the most widely used soft packing seal, also known as packing box seal. It uses oil-immersed graphite asbestos rope as the packing, which is placed in the packing box (packing box), compressed by the sleeve and gland, and achieved the seal by the deformation of the packing. When soft packing is used, a liquid seal ring is installed in the middle of the packing layer to introduce high-pressure liquid flow here, which can not only seal, but also lubricate and cool. In order to avoid too much friction between the packing and the pump shaft, the compactness of the packing should not be too large.

There are many kinds of fillers. In addition to asbestos, the basic materials can also be metal synthetic rubber, synthetic resin, leather shed hemp, slurry pump manufacturers, flexible asbestos fillers suitable for high and low temperature corrosive media and carbon fiber fillers suitable for high speed and high pressure,