There are five cases:
(1) Maintenance after gear wear
Gear wear parts of the main tooth meshing involute task surface and gear middle plane. When light and fine wear, the tooth surface can be polished with oil stone, and the middle is flat and polished on a flat plate. When the tooth surface of the gear is seriously worn, the new gear should be exchanged. If only the middle plane of the gear is worn, it can be grinded and polished on the surface grinder. When the module m=3, tooth number z=12, tooth profile Angle α=20°, tooth crest height coefficient F0 =1, tooth profile positive displacement coefficient X1 = X2 =0.5, the total geometric dimensions of each part are as follows.
Indexing circle diameter: D = Mz = 3x 12 = 36 (mm)
Tooth tip height: HA = m(F0 +x)= 3X (L +0.5) = 4.5 (mm)
Hf [=m(F0 +c-x) = 3X (L + 0.25-0.5) = 2.25 (mm)
Tooth height: H = HA + HF = 4.5 + 2.25 = 6.75 (mm)
Tooth tip diameter: DA = D + 2HA =36 + 2x4.5 = 45 (mm)
Flow chord tooth thickness: SXN = m (π/2* cos2a + xsin2a)= 3 x (1. 387 + 0.6428x0.5)=5. 125(mm)
Tooth height for measuring flow chord tooth thickness: HXN = m(π/8* sin2a + xsin2a)= 3X (0.7476x0.117x0.5)= 2.42 (mm)
Modulus M3 displacement coefficient x 0.5
Tooth profile Angle o20° flow chord tooth thickness sxn5. 12
Peak height coefficient F1 flow chord tooth thickness measurement maximum tooth height HXN2.42
Teeth z12
(2) Maintenance after shaft wear
The wear of the shaft of the gear oil pump is mainly if the friction between the middle of the shaft and the supporting needle is worn, so that the shaft diameter becomes smaller. If it is light and fine wear, can be plated with a layer of hard chromium to increase the diameter of the shaft in this part, so that the shaft is repaired. If the shaft wear is serious, it should be 45 steel or 40Cr steel from scratch, the shaft blank after rough, fine car, bearing parts to heat processing, hardness is HRC60-65, and then through grinding, so that the bearing joint part of the rough RA is not greater than 0.32μm; The allowance of roundness and cylindricity of the shaft is 0.005mm; Joint part with gear according to H7 / H6, rough RA should not be greater than 0.63μm.
(3) maintenance of pump body after wear
Pump body is generally worn if the oil absorption area section of the circular arc task surface. If the light and fine wear, can be used after grinding oil stone to deburr. Pump body is made of cast iron blank forming, heavy wear should be exchanged for new pieces. If the middle surface of the pump gear is repaired by grinding, the width size of the pump body should also be modified to be equal to the size removed by the middle grinding of the gear. The middle surface of the pump body should meet the technical requirements shown in Figure 3 after the initial machining.
(4) Maintenance of the middle cover after wear
The end cover of
KCB gear pump is made of cast iron. After the wear phenomenon, the light and fine can be ground on the flat plate, and the wear bucket strength should be ground on the surface grinder when it is serious. The end cover after grinding is in contact with the plane adjacent to the joint operation of the pump body
Not less than 85%. Flatness allowance, verticality allowance for center line of end face hole, parallelism allowance for center line of middle face and parallelism allowance for center line of two axis hole are all O.O.Lmm. The rough ra after grinding should not be greater than 1.5 μm.
(5) maintenance and exchange of needle roller bearings for pumps
After maintenance of parts in the pump, bearing needles should be exchanged (generally in the body of the epoxy resin pump). The requirements for needle rolling are: the size error of the diameter of the whole needle rolling should not exceed 0.003mm, the allowable length is 0.1mm, and the joint clearance with the shaft should be within O.olmm; When removing the needle roller, it should be filled in the bearing housing according to the number of requirements, and the needle roller should be arranged in parallel with each other.
The above knowledge is provided by berth oil pump www.hinapump.com.
