How to manufacture a good dredge pump?
Dredge pump manufacture process is an important step in achieving high quality products and cost effective control. In the past five years, Do Pump has continuously invested upgrade the manufacturing equipment and facilities of the sand pump factory, management and system optimization, optimize the manufacturing process, in order to make the sand pump sand ship products continue to improve and upgrade, and the product quality has been greatly improved. The product life cycle is greatly extended and production costs are controlled. Do Pump continuously strengthen technical and process training, strictly implement process procedures and process disciplines, in order to achieve customer statisfication globally.
Good dredge pump-pump design
dredge pump are designed with characters of high working efficiency, large particle pass, long transfer distance, high concentration of solid, deep working condition under the water.
For example,
1. DOD dredge pump are normally design of 80% or above working efficiency, the more working efficiency pump is the less engine power it requires, a pump with 40% working efficienncy will requir double engine power than pump 80% working efficiency.
2. EL electric dredge pump is designed with 60% solid concentration by weight, and they can work -150 meter in dredging condition.
3. DOS gravel dredge pump are designed with large particle pass ability, where different characters of solid will encounter in dredge work.
Manufacture Good dredge pump-pump pattern
1. An improvement of a dredge pump casing pattern is provided, including a casing model core box, characterized in that a plurality of rib holes are formed on the casing core box. The utility model has the advantages that the reinforcing rib hole opened on the core box can connect the upper and lower walls of the sheath through the reinforcing rib hole in the molten iron casting process. During the cooling and solidification process of molten iron, the molten iron inside the rib-shaped cavity will form a cylindrical reinforcing rib. Because these ribs are evenly distributed, the force acting on the upper and lower walls of the sheath is also uniform, so that the sheath is applied up and down. The wall has a good supporting force, and the flow path cavity between the upper and lower walls of the sheath will not be deformed.
2. Dredge pump impeller pattern is designed under CAD design system which was developed in a Microsoft Visual C++ environment. The program system of the CAD system has been designed with the method of software engineering. The CAD can provide Computational Fluid Dynamics CFD, more than that, 3-D solid mass design and emulation of spatial warping blade in dredge pump is carried out.
Manufacture Good Dredge pump-casting
The original sand selection criteria are as follows
1. Strength is suitable for dredge pump casting. Excessively high and too low strength are unfavorable. Excessive strength will affect the shrinkage of the casting and cause cracks in the casting. If the strength is too low, it will easily collapse, and the sand will form defects. Casting scrap
2. Good ventilation and reduce the appearance of pores. The hazard of the pores is huge. If the pores of the dredge pump jacket appear, the service life will be shortened.
3. The refractoriness is good, and the low refractoriness will cause the casting to stick sand.
4. Good collapsibility, otherwise it will seriously affect the surface quality of castings.
Pouring solidification is the process of pouring molten metal into a mold.
Casting position should follow the principle
1. The important part of the dredge pump casting should be placed in the lower part
2. Important processing face down
3. Casting face down
4. Ensure that the casting is full
5. Conducive to the positioning, stabilization and exhaust of the sand core
6. The joint position, pouring position and casting cooling position should be consistent
After the pouring is completed, the solidification is to be formed, the temperature is lowered to a certain standard, and the box is cleaned.
The box cleaning is mainly to clean the gravel and burrs on the surface of the casting.
Manufacture Good dredge pump-Pump heat treatment
The high-chromium cast iron is inhomogeneous composition, has structural segregation, coarse grains, contains some pearlite and vegetable body, and has large casting stress, which reduces the mechanical properties of high-chromium cast iron, making it unable to fully play. Due to its superior characteristics, the life of castings is shortened. Therefore, heat treatment must be carried out. The ideal metallographic structure of the high-chromium cast iron dredge pump over-flow component after heat treatment is: martensite + carbide + austenite. Due to the poor thermal conductivity of high-chromium cast iron, it should be slowly heated when the temperature is below 750 °C, and air-cooled or air-cooled after the high temperature is released. We compared heat treatment with five heating temperatures and three tempering temperatures. Through production test and comparison, the quenching performance is optimal at 980 °C, and the sheath life is the longest. Therefore, we finally determined that the heat treatment process is: 980 ° C air cooling + 280 ° C tempering air cooling. After tempering above 350 °C, the toughness of the casting is improved, the hardness is decreased, the wear resistance is slightly decreased, the hardness of the quenched casting below and above 980 °C is decreased, and the wear resistance is also lowered.
Manufacture Good dredge pump-dredge pump machining
Dredge pump machining process: refers to the process of machining the blank parts of the dredge pump into lathes by turning, drilling and boring. For mechanical parts, it is generally necessary to machine them to achieve the precise dimensions of the assembly.
Manufacture Good dredge pump-dredge pump assembly
Shaft Side Assembly
1. Install the O-ring on the pump shaft, install the disassembly ring, the bushing, and then hoist the pump body. The pump body is fastened to the bracket with bolts.
2. Install the decompression cover, seal the rubber pad, lift the rear guard plate, fasten it to the pump body with bolts, place the impeller O-ring, lift the impeller and sheath, and press the sheath on the pump body with bolts and fixed pressure plate. ;
3. Install a gasket, a front guard plate, and finally a pump body and a pump cover in the pump cover;
4. Then tighten the pump cover bolts, pay attention to the direction of the pump cover bolts, and install them symmetrically;
5. When assembling, it must be noted that the gaskets should be placed in the correct position and pressed.
Packing Seal Assembly
1. The impeller and packing combined seal includes an impeller, a pressure reducing cover, a bushing, a packing, a front water sealing ring and a packing gland;
2. When assembling, it should be noted that the position of each sealing ring must be installed correctly.
Dredge pump bearing assembly
1. Preheat the bearing during assembly, the oil temperature should generally not exceed 120 °;
2. For the bearing clearance, the product has been adjusted before leaving the factory, generally around 0.2-0.5mm, but the user should pay attention to the disassembly and repair or replacement of new bearings: in order to ensure the bearing clearance, the bearing gland should be The gap between the bracket body and the papermaking pad adjusts the gap of the dredge pump bearing assembly to ensure that the gap of the bearing assembly is between 0.2 and 0.5.
3. The bearing body is equipped with oil mark. The oil level should always be kept in the middle position of the oil mark. The lubricating oil is generally 20#, 30#, 40# mechanical oil.
The assembly part of the dredge pump is mainly composed of the above three parts. It should be assembled in strict accordance with the requirements when assembling each part. Any unreasonable assembly may cause big problems, strictly implement the quality control program standards, and manufacture the quality of the dredge pump products.
