First, the packing seal maintenance methods:
1, wash stuffing box, and check the shaft surface for scratches, burrs and so on. Stuffing box should be clean, shaft surface should be smooth.
2, check the shaft runout, rotor unbalance should be within the allowable range, so as not to vibration is too large, unfavorable to the packing.
3, in the stuffing box and the shaft surface sealant or coated with a suitable lubricant.
4, the packaging of the roll of packing, first take the root and journal size the same stick, the filler wound on it, and then cut off the knife, the best knife was 45 ° bevel.
5, packing to be filled by root, not a few filling. The method is to take a filler, coated with a lubricant, hands holding each end of the filler port, opened along the axial direction, so that the spiral, and then from the incision into the journal. Do not pull along the radial direction to avoid misalignment of the interface.
6. Take a metal bushing with the same size material or lower shaft hardness as the stuffing box, push the packing into the deep part of the box, and apply a certain pressure to the bushing with the gland so as to pre-compress the packing. Pre-compression of 5% to 10%, up to 20%. Rotate the shaft a second time and remove the sleeve.
7, in the same way, filling the second root, third root. Note that when the filler is 4 to 8, the interface should be staggered by 90 ° when filling; the two filler should be staggered by 180 °; and the 3 ~ 6 should be staggered by 120 ° to prevent leakage through the interface.
8, the last packing filling, the application of gland compression, but the pressure should not be too large. At the same time by hand rotation axis, the assembly pressure tends to parabolic distribution. Then relax the lid a little.
9, run the test, if not sealed, and then squeeze some of the packing; if the heat is too large, relax it. This transfer was only droplet-like leaks and fever is not so far (the temperature of the filler site can only be higher than the ambient temperature 30 ~ 40 ℃), it can be formally put into use.
Centrifugal pump packing seal assembly technical requirements when installing packing seals , should comply with the provisions of technical documents. If not specified, the following requirements should be met:
1, check the shaft radial seal at the amount of beating, the shaft allows radial runout in the range of 0.03 ~ 0.08mm;
2, the diameter of the liquid seal ring and the shaft sleeve clearance is generally 1.00 ~ 1.50mm, liquid seal ring and the filler box diameter clearance is generally 0.15 ~ 0.20mm;
3, packing gland and sleeve diameter gap is generally 0.75 ~ 1.00 mm, the gap should be uniform around;
4, packing gland and packing box diameter clearance is generally 0.10 ~ 0.30 mm;
5, there is a filler bottom ring, the diameter of the bottom ring and the shaft sleeve clearance is generally 0.70 ~ 1.00 mm;
6, the packing compression, liquid seal ring into the liquid hole should be aligned with the liquid seal, or liquid seal ring slightly to the outside;
7, for the roll packing, take a stick with the same size before the shaft, the filler wound on it, and then cut off the knife, the best incision was 45 ° incline.
Second, the technical standards for coupling maintenance:
Small machine coupling mainly rigid coupling, tooth-shaped coupling and flexible coupling several are as follows:
(A) Rigid Couplings Rigid couplings are generally used in centrifugal pumps of small power. When the valves are repaired, the bolts and rubber elastic rings are firstly removed. For the liquid with low temperature, the clearance between the two coupling halves is 2.2 ~ 4.2mm, the temperature is higher, should be larger than the shaft channeling amount of 1.55 ~ 2.05 mm. Coupling rubber elastic ring should be smaller than the perforation diameter 0.15 ~ 0.35 mm. At the same time disassembly must use special tools, keep smooth, do not allow scratches scratch.
(B) Toothed coupling Toothed coupling flexibility is better, with automatic centering performance. General maintenance by the following methods:
1, check the coupling tooth surface engagement, the contact area along the tooth height not less than 50%, along the tooth width of not less than 70%, no serious pitting tooth surface, wear and tear.
2, the outer ring gear coupling ring beating not more than 0.03mm, round beating not more than 0.02mm.
3, if you want to remove the ring gear, you must use special tools, not beat, so as not to bend or damage the shaft. When reassembly, the ring gear should be heated to about 200 ℃ before reloading to the shaft. External gear and shaft interference is generally 0.01 ~ 0.03mm.
4, back to the middle of the barrel or other parts should be assembled according to the original mark and data.
5, with a torque wrench evenly tighten the bolts.
Third, the diaphragm flexible coupling:
1, cleaning check two and a half coupling surface, there should be no cracks, wear, and the surface of the spacer sleeve should be smooth, no glitches, coaxial coupling deviation of both halves should be less than 0.003mm.
2, cleaning and check the spring, there should be no cracks, deformation.
3, clean and check the bolts, the surface should be no cracks, wear, deformation.
4, find the correct requirements: axial ± 0.03mm, ± 0.05mm radial.