1) 圖5-53a 型結構:其連接螺釘應為銷和釘合一，調整墊為調整泵葉輪對中用。電動機和泵軸頭螺母為固定各自的軸用，調整墊般是整塊的，分半也可。
Classification of rigid couplings for vertical slurry pumps
1. Vertical pump rigid coupling
The rigid coupling of vertical pump is shown in Figure 5-53. This is the coupling used to connect the pump and motor. When the pump itself is equipped with thrust bearing, the pump coupling can be a flexible coupling, just like the coupling used for horizontal pump. When the axial force of the pump and the mass of the pump body are borne by the motor, the following four functions must be possessed: the coupling must be rigid, and bear the axial force and mass of the pump. At the same time, it must be able to adjust the alignment of the pump rotor, and also ensure the concentricity of the two shafts and the transmission of torque. If the pump center can be adjusted at the motor end, the coupling has only two functions. The pump coupling can be lengthened, as shown in Fig. 5-53c, or not, as shown in Fig. 5-53a ↓ b, d, e. If the pump is equipped with a mechanical seal, the pump coupling shall be extended to facilitate the replacement of the mechanical seal. The following several types of rigid couplings are recommended for reference.
1) Fig. 5-53 a-type structure: the connecting screw shall be a pin and a nail, and the adjusting pad is used to adjust the alignment of the pump impeller. The motor and pump shaft head nuts are used to fix their respective shafts, and the adjusting pads are generally monolithic or can be split in half.
2) Fig. 5-53 B-type structure: the connecting screw is also a combination of pin and nail, and the adjusting block and the pump shaft head nut are one by one, which can adjust the centering problem of the pump rotor impeller, and finally tighten it with the connecting bolt.
The connecting holes on the adjustment blocks of 1) and 2) above are larger and do not play a matching role.
3) Fig. 5-53d structure: The motor shaft is positioned by snap ring. After the pump shaft is adjusted to a certain position, it is positioned by passing through the Huff coupling with a cylindrical pin.
4) Figure 5-53e type structure: the motor is positioned by snap ring, which is the same as 3), while the pump shaft uses the thickness of the adjusting block to adjust the alignment of the pump impeller, and finally uses the shaft head screw to tighten it, which is also the positioning of the Huff coupling.
5) The coupling of vertical pump also requires a cover on the motor base (bracket) window.
2. Shaft coupling
The shaft coupling is shown in Figure 5-56. This refers to the coupling parts used to connect the pump shaft and pump shaft. It must also be rigid, and bear the axial force and mass of the pump, and can ensure that the two shafts are coaxial, and can also transmit torque. Its three functions are necessary.
The following types of couplings are recommended for reference:
1) The form shown in Figure 5-56a is threaded connection. The transmission makes the thread tighten more and more depending on the rotation speed. The structure is simple. There is also a section behind the thread that fits and locates with the shaft. It is generally used for small pumps.
2) The form shown in Figure 5-56b is ferrule connection, which is widely used in the pump industry. The upper and lower shafts are connected by split ferrules, and their outer diameters are limited by shaft sleeves.
3) The shown form is that two shaft heads are connected with studs, or one shaft end is connected with threads, as shown in Fig. 5-56f. A shaft sleeve is added outside to transmit torque with a key, and the shaft sleeve is fixed on the key with a jackscrew for positioning.
4) As shown in Fig. 5-56g, the upper and lower shafts use split snap rings with shaft sleeves in the middle, and the upper and lower intermediate shaft sleeves are tightened and positioned with nuts, and the keys transmit torque.
5) The form shown in Figure 5-56h is similar to the structure shown in Figure 5-56b. The two shafts are also connected by ferrules, and the outside is a Huff coupling.
The pump coupling and shaft coupling here are two different concepts. The former has the difference between rigidity and flexibility, and the difference between lengthening and non lengthening. The latter must be rigid, without lengthening.
3. Adjust the center of the pump impeller at the motor end
Adjust the center of the pump impeller at the motor end as shown in Fig. 5-57. Deep well pumps and small condensate pumps can adjust the center of the pump impeller at the motor end. At this time, the pump coupling is not used, but only the shaft coupling. The motor rotor is hollow. The motor shaft passes through the hollow and passes through the support block (also called the motor coupling). The adjustment nut is used for axial adjustment, and the fastening screw is used to tighten it.