A large inclined axial flow pump application 1.1 Overview Large inclined axial flow pump because of its good hydraulic performance, a small excavation depth, plant height is low, the unit force evenly, etc., more and more by the height of different users Attention, especially low head (<3m) large flow (1.2 unit overall layout of the entire pump unit system has inlet and outlet flow channel section, the pump section, the gearbox section, the motor section and auxiliary equipment, etc. The pump is 15 ° inclined installation, The blade is semi-adjusted; using medium speed motor, the motor speed is 1000r / min, through the two gear boxes decelerating transmission, the pump speed is 73r / min, inlet flow elbow into the water, Using fast gate to cut off the flow 1.3 The numerical calculation of the flow channel The inlet channel is an elbow pipe and the outlet channel is a variable-diameter diffuser pipe, both of which act as a guide for water flow and install a quick gate to cut off flow outside the outlet channel. Part of the use of reinforced concrete structure.Flow channel inlet to the impeller center height of 4.25m, impeller inundation depth 3.5m above the center of the impeller.Traditional The runner assembly test is to design the runner of the model pump according to the control size of the prototype unit, and after the test, the runner or hydraulic components are trimmed until the design requirements are met. Usually, the time, manpower, energy and material resources invested in this process Are quite large.Water inlet and outlet of the project specifically requested the Wuhan University of Hydraulic and Electric University of fluid flow numerical calculation, through the fluid numerical calculation, the hydraulic loss of the runner is 0.5m, by the Ministry of Water Resources Tianjin Water Resources and Hydropower Design and Research Institute research institute model device test results show that the fluid numerical calculation of the loss and the test results are basically consistent with the results of this large-scale pumping station for the future to provide a theoretical basis for Figure 1 is calculated through the fluid numerical model flow Road form. 2 Large-scale inclined axial flow pump design Pump design in strict accordance with the requirements of the tender documents and the implementation of national standards; prototype pump performance parameters based on the model device test to determine the prototyping pump hydraulic components to strict design model device according to a similar law design See design calculations and drawings). 2.1 Pump Structure Pump part of the rotor parts, pump shaft parts, guide bearing parts, pump parts, pump shaft seals, thrust radial bearing assembly composition, the motor through two parallel gear drive and pump connection, the overall appearance of the unit (Please see Figure 2) 2.2 Wheel parts Wheel is the heart of the pump unit, the rotor body, blades, pressure plate, etc. The blade is ZG0Cr13Ni4Mo stainless steel monolithic casting, the blade Leaf design According to the model blade in strict accordance with the geometric similarity conversion, the casting after heat treatment to eliminate stress, the blade surface to remove sand and surface sclerosis grinding, in the three-axis coordinate system RBI to identify the center of rotation and 0o benchmark Line blade is to ensure that the performance of the pump key, because the blade is a space surface, the traditional pump blades are not machined, on the one hand by the processing equipment constraints, on the other hand affected by the traditional concepts, therefore It is hard to guarantee whether the performance indexes of the prototype pump set can meet the expected requirements. The project leaves open the machining precedent for large pumps and uses the most advanced five-axis CNC machining today. By comparing the model pump blade numerical control processing with the RBI processing, the blade efficiency index of CNC machining can be increased by 1.5%, and the device efficiency reaches 69% when the designed head lift is 1.39m. Blade processing accuracy greatly improved, so that the blade line deviation (tender requirements for ± 6.15mm, drawing requirements are increased to ± 4mm), surface wave, the blade surface roughness and the weight of the blade and other important quality indicators are poor So as to provide a good guarantee for efficient and stable operation of the pumping station. The design weight of a single leaf of this project is 1950kg. According to the traditional weight difference between two leaves is not more than 150kg, which has a great impact on the balance weight of runner body. The static balance can not be guaranteed, which will affect the stability of unit operation . Blade NC processing, the weight difference between the two leaves only 6kg, the weight of the runner body is small, static balance accuracy greatly increased, and thus the stability of the unit has a reliable guarantee. The cross section of the blade inlet side of the test; ZG270-500 rotator body cast as a whole, the ball using CNC machining; blades using screws and plate fixed to the rotor body, the blade angle using cylindrical pin positioning, and according to the requirements , Adjust the blade angle (angle range of -4 ° ~ +4 °), so that the blade is fixed at an angle operation, blade factory angle set at +2 °. 2.3 pump shaft parts The pump shaft is a hollow shaft flange at one end, the pump shaft flange and the rotor body is coupled, the pump shaft and the rotor body bolt connection transverse pin transmission torque, the upper end of the pump shaft and the drum gear coupling key connection, Through the drum gear coupling and the gear box shaft associated drum gear coupling there is still a gap in order to adjust the pump shaft and gear box shaft axial distance and concentricity; pump shaft and pump rotating part of the sliding bearing and Thrust combination roller bearings support axial force and radial force, roller bearings use spherical spherical roller thrust bearings. The material of the shaft of the pump is the whole steel forging 35, which is 8085mm in length, which is the longest part of the pump. According to the calculation, the diameter of the shaft of the pump is Φ360mm, the strength and rigidity of the shaft can be guaranteed and the safety factor is sufficient; The pump is inclined installation, the stiffness of the shaft will affect the bearing capacity and the pump running stability, so the design of the pump shaft in order to improve the rigidity of the shaft diameter increased to Φ410mm, and in the middle of the shaft to fight The holes remove the metal evacuated from the forged shaft and reduce the deflection of the shaft itself. In the guide bearing and packing seal contact parts, the welding of the shaft 3Cr13 hard alloy to improve the pump shaft surface hardness and wear resistance, the surface hardness of HRC50 above; and the use of special equipment for grinding parts of the journal, Guide bearing parts journal surface roughness of less than 0.8μm. 3 The selection of water guide bearing components Water guide bearing is the key technology of inclined pump unit, but also affect the reliable operation of the unit key components. To this end, the domestic has been built inclined units in the use of water-bearing more or less there have been problems. Taipuhe pumping station with pump water guide bearing on the choice of domestic and foreign manufacturers of bearings related to the technology, products were extensively studied, combined with the relevant domestic bearing experts advice, decided to use Spain Sde Wa company's marine stern shaft Bearing products; the guide bearing thin oil-lubricated bearings; bearing material tin-based white metal bearing material, the use of gravity oil bearing lubrication, lubricating oil from the outside through the guide vane holes into the bearing within the oil bath lubrication, the whole Bearing completely immersed in oil to be fully lubricated, the lower part has a back to the oil hole, the bearing can be regularly replaced inside the lubricating oil, and with two temperature measuring element; bearing body and bearing are axial half structure, bearings and bearings Body using spherical contact, so that the bearing can rotate in the bearing body with self-tuning function, can eliminate the poor shaft alignment and run-time imbalance caused by uneven bearing force phenomenon; both ends of the bearing are provided with two Road skeleton seal, seal between the two skeletons are also used gravity oil lubrication. Guide bearing according to the radial load of 27 tons design, according to the calculation, the guide bearing can choose the maximum load of 35 tons. 4 part of the design of the pump body 4.1 pump body part of the pump body, including the front cone, telescopic casing, impeller shell, guide vane body, adjustable pipe bend, extension pipe and other parts, the combination of flange face rigid connection rubber asbestos seal The impeller shell, the guide vane body and the variable-diameter elbow are all axial halves so as to facilitate the installation and maintenance of the pumping station. Bolts are used on the half of the shaft, and the conical pin is positioned and the rubber asbestos plate is sealed. Impeller shell with ZG270-500 matrix, lined with stainless steel to improve its anti-cavitation performance, at the top and bottom of the impeller shell are provided with observation holes, easy to observe the blade operation and installation, maintenance and measurement of blade clearance and guide bearing wear, The single-sided clearance between the blade and the shell is about 4mm; the guide vane body adopts the structure, the flange of the guide vane body and the barrel are welded by the high-quality steel plate Q235-A, which can ensure good appearance quality and surface roughness, The guide vane mold airfoil to be tested, the airfoil meets the drawings requirements, the guide vane to take a single piece of cast, made of ZG270-500 cast steel, guide vane surface grinding process, the surface roughness of not more than 12.5μm ,, and then guide After positioning the leaves welded, so as to ensure that parts and drawings consistent, but also to ensure that the guide vane hydraulic performance. Other parts are used Q235-A structure; the top of the reduction pipe is provided with access holes for installation and maintenance spare; in the pre-cone, impeller shell, guide vane body, adjustable pipe bend, the extension of the pipe With support feet, adjust the adjustment horn, easy to adjust the elevation and level when installed; the front cone pipe is the water inlet and water pump connection, in order to facilitate the pumping station installation, the former conical pipe from a period of concrete buried to phase II Concrete buried, in order to effectively prevent the pouring of concrete after the second period of water seepage phenomenon, the length of the pre-tapered tube from 700mm to 1000mm, the flange diameter Φ4800mm increased to Φ4900mm; before the conical tube, adjustable elbow (down), extension tube After all the installation of the pump, it is necessary to cast two concrete embedded in the foundation. 4.2 Shaft Seal Parts & nbsp;
MRL / Overhead Traction Elevator Packages
MRL / Overhead traction elevator packages are designed to provide independent and OEM elevator contractors with reliable, turn-key, custom solutions for any modernization or new construction project
Passenger Lifts
Panoramic Elevators
MRL Elevators
Villa Lifts
Home Lifts
Hospital Bed Elevators
Freight Elevators
Car Elevators
Dumberwaiter Elevators
Service Elevators
Our elevator regeneration team has extensive knowledge and is supported by our in-house technical design, manufacturing facilities, allowing us to offer modernization solutions of all types and complexity from single elevator, low rise installations to multi elevator, high rise group systems
MRL Elevator Packages,Overhead Traction Elevator Packages,Traction Elevator Packages
CEP Elevator Products ( China ) Co., Ltd. , https://www.zjsmartcommercialescalators.com