Precautions for pump installation

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1. The longitudinal and transverse centerlines, elevation reference lines, and coordinate lines shall be clearly marked on the foundation； 2. The area where the shims are to be placed (within 50 mm around them) should be leveled; the allowable deviation in levelness for this area is 2 mm/m. Any debris present in the holes reserved for the foot bolts must be removed completely. Alignment should be done with reference to the pump’s axis; if there is an intermediate machine connecting the driver and the pump, alignment should be performed with reference to the axis of the intermediate machine. During the pump installation process, pump alignment is a critical step. 3. Initial alignment and leveling of the pump: A. The initial alignment and leveling of the pump should be carried out by making adjustments and taking measurements based on the reference lines on the foundation, in relation to the reference points on the pump body. The criteria for adjustment and measurement are specified as follows: a. The leveling and alignment of the pump should be based on the inlet and outlet flange surfaces ； b、Mechanically processed surface of the pump body ； c. The journal or exposed surface of rotating components ； d. The end face and outer circumferential surface of the coupling. On the aforementioned reference plane, use a level to make measurements and adjustments at the four orientation points. B. The alignment and leveling of the pump shall meet the following quality standards: a. Alignment and leveling shall be carried out in two or more directions that are perpendicular to each other within the same plane ； b. Alignment and leveling should be carried out by using shims (or other adjustment elements) as required to achieve the desired precision in elevation; adjustments should not be made by tightening or loosening foundation bolts or applying local pressure ； c、Allowable deviation for the levelness of the pump: the allowable longitudinal levelness deviation is 0.1 millimeters per meter, and the allowable lateral levelness deviation is 0.2 millimeters per meter. It should be measured on the inlet and outlet flange surfaces of the pump or on other horizontal surfaces ； d. When measuring pumps used for transporting high-temperature or low-temperature liquids at normal temperature, a compensation value for temperature changes shall be reserved in accordance with the design specifications. 4. Layout of foot bolts and shims a. Foot bolts ① The bare portion of the foot bolt should be free from oil and oxidation; a small amount of grease should be applied to the threaded portion, and the threads, nuts, and washers should be properly protected ； ②The foundation bolts should be vertical with respect to the foundation and must not be tilted; the lower part of the bolts must not touch the bottom of the hole, and the distance between the bolts and the hole walls must be at least 15 mm ； ③After the nut is tightened, the bolt must protrude 1.5 to 3 times the pitch of the nut. b、Shims ● When arranging shims, it is principle to place one set on each side of the foot bolt, as close as possible to the bolt; the distance between adjacent shim sets should generally be around 500 mm ； ●Each set of shims should be placed firmly and in good contact with the foundation. After the equipment is adjusted, each set of shims should be tightened. Use a 0.05 mm feeler gauge to check the gaps between the shims as well as between the shims and the base surface; the total amount that can be inserted on either side of a shim at the same cross-section shall not exceed 1/3 of the shim’s length. ●After the pump is adjusted, the end face of the shims should extend beyond the outer edge of the equipment’s bottom surface; flat shims should protrude by 10–30 mm, while inclined shims should protrude by 10–15 mm. The length of the shim set extending into the equipment base should exceed the center of the foundation bolts. ●The number of shims shall not exceed four layers; they should be pressed tightly together, and the height of each shim should be 30–60 mm. ●The overlap length of the paired shims should be no less than 3/4 of their total length, and the inclination angle between them should not exceed 3 degrees. ●The shims should not be loose; after checking that they are secure when struck with a 0.25 kg hammer, they should be welded in place. The shims must not be welded to the pump base. 5. Secondary grouting: A. Secondary grouting can be carried out only after alignment and leveling have met the required standards, and after the \"Hidden Works Construction Record\" has been filled out. B. Before secondary grouting, clean the foundation and moisten it thoroughly with water. The thickness of the grout layer is generally 30–60 mm ； C. Grouting should be carried out using fine aggregate concrete, whose strength grade should be one level higher than that of the foundation concrete. One unit should be grouted at a time; pouring in stages is not allowed. The grout layer must be compacted firmly, and it should bond tightly with the foundation and the pump base, without any layering occurring. After grouting is complete, the grout layer needs to be cured. 6. Alignment of the coupling
A. When the driving shaft and driven shaft of a pump are connected via a coupling, their alignment is a critical process. The radial positioning of the two halves of the coupling, as well as the axial clearance and axis inclination, must all comply with the specifications outlined in the design documents. Fine adjustment of the coupling’s alignment should be carried out after the secondary grouting process. 7. Installation of pipes connected to the pump
A. The installation of pipes connected to the pump’s inlet and outlet should be carried out after proper alignment. Before installing the pipes, all dirt, scale, rust, weld spatter, and other foreign substances must be removed from inside the pipes ； B. The intake pipe and the outlet pipe should each have their own supports; the pump body must not bear the weight of the pipes directly ； C. The flange end faces that are connected to each other should be parallel; for threaded pipe fittings, the axes should be aligned, and forced connection using flange bolts or pipe fittings is not allowed.