Universal coupling installation instructions

2020年07月09日

Cross  Shaft  Universal  Coupling

By using its structural characteristics, cross shaft universal coupling can make two shafts with constant angular speed which are not in the same axis or with large axial deflection angle or axial movement. Its biggest characteristics are strong ability of displacement compensation in all directions, compact structure, high transmission efficiency and convenient maintenance. Heavy universal coupling is suitable for metallurgical machinery, heavy machinery, petroleum machinery, engineering machinery and lifting and transportation machinery, etc.

Ⅰ Features of universal coupling:

The main features of SWC (integral fork head) and SWP (split bearing pedestal) universal coupling are as follows:

1. It has large angle compensation ability, SWC axis bending angle can reach 15 °～ 25 ° and SWP type can reach 10 °.

2. The SWC type structure is compact and reasonable. The integral fork head is adopted, which eliminates the weak link of bolt pressing on the bearing pedestal (cover), and completely avoids the malignant events caused by bolt loosening or fracture, so as to make the work more reliable.

3. SWP type has large bearing capacity and is safe and reliable to use. Compared with the same type of coupling with the same rotary diameter, the torque transmitted by the coupling is larger, and the matching range of the mechanical equipment with limited rotary diameter is more advantageous, and the service life of the coupling is 30% ~ 50% longer than that of other types of coupling.

4.High transmission efficiency. Its transmission efficiency can reach 98% ~ 99.8%, and it can save more energy when used in high power transmission.

5. Stable transmission, low noise, convenient disassembly and maintenance. It can improve the quality of rolled products and improve the working conditions of operators.

SWC type integral fork type universal coupling can be divided into seven types: BH, BF, WD, CH, WH, WF and WD.

SWP type split bearing pedestal cross shaft universal coupling is divided into seven types: A, B, C, D, E, F , G.

Ⅱ Selection of universal coupling:

SWC and SWP type universal coupling is composed of two universal joints and one intermediate shaft. In order to make the angular velocity of driving and driven shafts equal, ω1 =ω2, the following three conditions must be met:

1. The joint inclination angle between the intermediate shaft and the driven shaft is equal, that isβ1 = β2.

2. The fork heads at both ends of the intermediate shaft are in the same phase.

3. The center lines of the drive shaft, driven shaft and intermediate shaft are in the same plane.

The installation form of universal coupling is generally divided into Z type (two shafts are parallel) and W type (two shafts intersect) according to the mutual position of their axes. See below

Universal coupling should be selected according to load characteristics, calculated torque, bearing life and working speed.

The calculated torque is determined by the following formula:

Tc = k T  T = 9 5 5 0 * P w / n      T = 7 0 2 0 * P h / n

In the formula：

T -- Theoretical  torque,N?m      TC-- calculated torque, N?m

PW -- driving power, kw           PH -- driving power, horsepower

n -- working speed , r / min        K -- working condition coefficient, see table

According to the calculated torque, shaft diameter and speed, the type and structure size of the coupling can be selected from the relevant manuals according to the following conditions.

TC≤[T]            n≤n max

In the formula:

[t] is the allowable torque of the selected coupling (N?m)

n is the speed of the connected shaft (r / min)

n max is the maximum allowable speed of the selected coupling (r / min)

Working condition coefficient K

Ⅲ Installation, use and maintenance of cross shaft universal coupling

1. Before the installation of the cross shaft universal coupling, clean the two end faces, check the fit of the end face key notch, and then tighten the screws, which are not allowed to be loose. When the spline shaft of the cross shaft universal coupling is separated from the spline sleeve, and then the spline shaft is meshed with the spline sleeve, the two arrows must be aligned and assembled according to the arrow on the coupling. The flange connecting bolt can only be installed from one end of the half coupling matched with the flange of the cross shaft universal coupling, The nut is tightened by the flange side of the cross shaft universal coupling (as shown in the figure below). The mechanical properties of bolts shall meet the requirements of grade 10.9 in GB / T3098.1-2000, and the mechanical properties of nuts shall meet the requirements of Grade 10 in GB / T3098.2-2000.

2. After the cross shaft universal coupling is installed, it is necessary to check all the fastening screws for normal operation for one shift. If it is found to be loose, it must be tightened again with the specified tightening torque, so as to ensure that it will not be loosened

3. The sliding surface, cross shaft and bearing of cross shaft type universal coupling must be lubricated. Generally, 2# industrial lithium grease or 2# molybdenum disulfide calcium grease shall be used. The newly manufactured coupling has been greased, so there is no need to add grease immediately. The coupling stored for more than 6 months should be re greased. Under normal conditions, add grease once every 500 hours of continuous operation and once every 2 months of intermittent operation. If working under high temperature (no more than 250℃), grease must be added once a week. When adding grease, screw off the oil hole plug on the bearing end face and inject it with high-pressure oil gun until overflow. Our company is not responsible for the damage of cross shaft universal coupling caused by not adding grease as required.

4. Generally, the cross shaft universal coupling must be maintained once every 3 months. If normal wear such as indentation is found, it should be replaced in time.

5. In order to prolong the service life of universal coupling, after maintenance and cleaning, the cross shaft should be rotated 180 °for installation, so that the journal can be used alternately.

6. Long term overload use should be avoided to avoid the occurrence of operation accidents.

7. During the operation, it is necessary to observe whether the cross shaft universal coupling has abnormal radial swing and bearing heating, and it must be repaired in time.

8. Appropriate safety protection measures must be taken in all places where personal and equipment accidents may occur due to the running cross shaft universal coupling.