1. Packingseal :
Packing is the most commonly used a seal device, it is composed of a bottom lining ring, packing, seal ring, a water sealing pipe and packing gland, such as spare parts. The compaction degree of filler used to adjust the gland nut. If pressed too tight, the packing and the shaft sleeve friction increases, shorten the service life of the packing and the shaft sleeve, serious when will overheat, smoke, and even burned filler; if the pressure was too loose, in the increase of leakage, decrease the pump power. So the packing should be pressed for elastic, usually in every 30 minutes to 60 water leakage from shaft seal device for appropriate (about pumping of sewage or with a corrosive liquid, can not use the shaft seal equipment). Seal ring is a central concave peripheral projecting ring is provided with a plurality of holes, seal ring sealing pipe alignment. During the operation of water pump, pump high pressure water (or after washing water) passes through the canal into the seal ring seal, the introduction of packing seal, together also cooling, smooth effect.
More varieties of filler, agricultural pumps commonly used oil immersed asbestos packing, it is by impregnated graphite asbestos thread or wire stone cotton knitting and, with wear-resisting, heat-resisting, soft and fine smooth characteristic. In order to ensure that the packing seal has a good working condition, the wear or hardening of the filler, should be replaced in a timely manner. The packing seal has the advantages of simple structure, low cost, convenient assembly and disassembly, short service life and poor sealing performance.
2. Mechanical seal :
Mechanical seal, also known as seal, which is mainly composed of a movable ring (with the pump shaft rotates together), static ring fixed on the pump body), a pressing spring and a sealing rubber ring, etc., wherein. A movable ring bright face by the spring and the water pressure tightly on the static ring bright face and radial sealing together by a sealing rubber ring end axial seal. The utility model has the advantages of compact structure, small mechanical friction and reliable sealing function, but the manufacturing technology of the utility model has the advantages of high requirements. Mechanical seals are widely used for pumping sewage, with corrosive liquid sealing request higher occasions. In some diving electric pump and sprinkler self-priming pump can also be selected
