【正文】 arantee the max tolerance △(△=δ1δ2) smaller than [See Figure3, (b)]. The other method is the use of plug gauge and magnetic centigrade scale. We fix magnetic centigrade scale on outside diameter of one coupling and put measuring head on outside diameter of the other coupling. The pulsation of centigrade scale should be smaller than [See Figure3, (c)] when turn rotor. We check up the space between couplings with plug gauge to ensure the max tolerance less than [See Figure3, (b)] The shaft of pump and the motor should assured the parallelism when pumps are drove by belts, so we adjust direction on the basis of pulley. When central distance is small, we can align end faces of pulley with ruler。 Another type is ZJL, as singlestage singlesuction vertical axial inhalation centrifugal slurry pump. 1．ZJ Structural feature and type of ZJ slurry pumps（1）ZJ Pump Structure Feature ① Pump Head It is a horizontal cantilevered slurry doublecases pump. The pump head includes cases, impeller, and shaft seal. Doublecases pump centrally split vertical split direction. Discharge port can be positioned at 8 different position at an interval of 45176。CONTENTSⅠ USES AND SCOPE OF APPLICATION …………………………………… 1Ⅱ PATTERN、STRUCTURAL FEATURE OF PUMPS …………………… 1Ⅲ SLING、INSTALLATION、ADJUSTMENT AND TEST RUN OF PUMPS ……… 6Ⅳ COMMON FAILURE AND HANDING MEASURE …………………… 22Ⅴ MAINTENANCE AND DISMOUNTING OF PUMPS ……………………… 28Ⅵ LIST OF QUICKWEAR PARTS ……………………………………………36VII LIST OF SPECIAL TOOLS……………………………………………… 38ATTENTION1. The direction of motor must keep consistent with arrow on the Front casing. Before testing running the motor, the motor must be separated from pump. The shafts of Motor and pump are strictly forbidden to rotate reversely。.The outside cases made by HT200 or HT5007, connecting with bolts. The inside cases (volute case, front liner, back liner) made by highchrome alloy or rubber materials.Impeller front and back cover plates with back vanes to reduce leakage and increase operating life, impeller and shaft is firmly connected by laddershaped with disassembly ring, ”O(jiān)” rubber ring is used between liner and volute casing and it is very convenient and reliable.There are three kinds of shaft seal type, expeller shaft seal, packing shaft seal and mechanical seal, see Expeller shaft seal is made of stuffing box, expeller, lantern ring, packing, packing gland and shaft sleeve, see 5 Packing shaft seal is made of stuffing box, spacer sleeves,lantern ring, packing, packing gland and shaft sleeve, see 。 when central distance is big, and we can adjust them by aligning end faces through span wire system [See Figure, (4)]. (a) (b) (c) 　 Figure 3 Capturing of coupling Figure 4 Capturing of belt wheels(3) Configuration and requirement of discharge pipeline and suction pipeline According to the applied condition and the cavitation performance of pump, the arrangement of pump can be classified into exalted setting [See Figure5, (a)] and low setting [See Figure5, ( b)].Figure 5 Arrangement of suction pipeline and discharge pipeline① Suction pipelineDiameter of suction pipeline: diameter of suction pipeline should be equal to pump inlet or larger than it so as to avoid cavitation and deposition of slurry in pipeline.Gate valve of suction pipeline: In order to maintain easily, we should install inlet gate valves whose diameter is equal to the diameter of suction pipeline. The expansion pipe should be set up between inlet of pump and suction pipeline so as to disassemble pump.② Discharge pipelineDiameter of discharge pipeline: diameter of discharge pipeline is usually bigger than outlet of pump because diameter of discharge pipeline is related to properties of slurries and sedimentation flow rate.Gate valve of discharge pipeline: Diameter of outlet gate valve is equal to diameter of discharge pipeline.Piezometer: The piezometer should be set up on the ascending pipe between outlet of pump and the first valve.③ Points for configuration of pipelineThe diameter of pipeline is related to system resistance, critical sedimentation velocity of slurry etc. Before inlet of pump, onestage pipe longer than 3 times diameter of pipeline had better be installed. The velocity of slurry is between and m/s, which is determined by critical sedimentation velocity of slurry. When we install suction pipe in suction arrangement we adopt pipe of varying diameter whose upper generating line is horizontal to avoid cavitation (See Figure, 6). Figure 6 Reducing pipe with horizontal upper generating line When we adjust the capacity of pump with throttle, throttle should be installed on the discharge pipeline. When throttle is fixed on suction pipeline, cavity will happen easily.(4) Pipelines of watersealing and watercoolingPacking seal will be equipped with stubs and piezometer. We must install pressure gauge on shaft seal water pipeline to adjust the pressure of shaft seal water. The setting of shaft seal water pipeline and watercooling pipeline are seen Figure7. The Shaft seal water Watercooling Figure 7 Arrangement of shaft seal water pipelineThe pressure of shaft seal water should be puted according as the following formula.Table 1 Pressure and Capacity of shaft seal waterSealing TypeThe Pressure of shaft seal water Pi’(Mpa)The flow of shaft seal water （m3/h）G1/4”G3/8”G1/2”G3/4”Expeller Seal （Ⅰstage pump)Pi’=1~~22~33~5Packing SealPi’=(i1/3)PMechanical SealPi’=P出+ pump flow 1%, when the flow is large choose small values, flow is small choose big value , but the minimum shaft seal water quantity not less than 1 m3 / h Note: This Table is suitable to single stage pump. When the suction pressure of pump is 0 (Pin=0), the pre