Coupler Pressing Machine Master The Assembly Of The Hub On The Shaft
Coupler Pressing Machine assembly, in the mechanical maintenance is a relatively simple maintenance process. In the Coupler Pressing Machine assembly key to master the hub of the assembly on the shaft, the Coupler Pressing Machine is connected to the two-axis alignment, parts inspection and assembly requirements according to the drawings and other links.
1) Assembly method of the hub on the shaft
The hub is one of the keys to the Coupler Pressing Machine installation on the shaft when assembling. The hub and the shaft are mostly interference fit, the connection is divided into key connection and keyless connection, the hub of the shaft hole is divided into cylindrical shaft hole and cone shaft hole two forms. Assembly methods are static pressure method, power press method, temperature assembly method and hydraulic assembly method.
(1) static press method
This method is based on the hub of the axle on the need to install the size of the different force, the use of clamps, jacks, manual or mobile presses, static pressure method is generally used for tapered shaft hole. As a result of the static pressure method to receive pressure machinery restrictions, in the larger interference, the application of a lot of force more difficult. At the same time, in the process of pressing the wheel and the shaft will be cut between the uneven surface of the uneven crest, so that the mating surface is damaged. Therefore, this method is generally not much application.
(2) dynamic press method
This method refers to the use of impact tools or machinery to complete the hub to the axis of the assembly process, generally used between the hub and the axis of the transition with the transition or interference is not the occasion. The assembly site is usually a method of hitting a hand hammer by placing a piece of wood, a lead block or other soft material on the end face of the hub as a cushion and pressing the hub against the impact of the hammer. This method of cast iron, quenching the fire of steel, casting alloys and other brittle materials made of the hub, the risk of local injury, should not be used. This method will also damage the surface with the complex, it is often used for low-speed and small Coupler Pressing Machine assembly.
(3) temperature difference assembly method
In the case of heating, the hub is thermally expanded or cooled by cooling to shrink the shaft end so that the inner diameter of the hub shaft is slightly larger than the diameter of the shaft end, i.e., the so-called "easy assembly value", without the need for large Force, you can easily set the hub on the shaft. This method has more advantages than the static press method, the power press method, for the use of brittle materials made of the hub, the use of temperature assembly method is very appropriate.
Temperature assembly method is mostly used heating method, the cooling method used less. There are a variety of heating methods, some of the wheels into the high flash point of the oil for oil bath heating or torch baking, and some with the oven to heat the assembly site to use more oil bath heating and torch baking. The maximum temperature at which the oil bath can be heated depends on the nature of the oil, typically below 200 ° C. The heating temperature of the hub can be increased by more than 200 ° C. If the heating temperature exceeds 430 ° C, it will cause a change in the internal structure of the steel, so the upper limit of the heating temperature must be less than 430 ° C. For insurance, the upper limit of the heating temperature should be below 400 ° C. The actual heating temperature required for the hub can be calculated based on the interference value of the hub and the shaft and the requirements for heating the rear axle on the hub.
(4) after the inspection of the assembly
After the hub of the Coupler Pressing Machine is assembled on the shaft, the vertical and coaxial degrees of the hub and the shaft should be carefully checked. Usually in the hub of the end and the outer circle set up two dial indicator, turning the wheel when the rotation, observe the hub of the whole beating (including the end of beating and radial run) values, determine the vertical axis and the axis of the axis and coaxial The situation of the situation. Different speed Coupler Pressing Machine of the requirements of the whole beating different values, different types of Coupler Pressing Machine on the requirements of the whole beating are also different, but the wheel assembly on the axis after the hub must be the total beating deviation of the value of Design requirements within the tolerance range, which is one of the main quality requirements of the Coupler Pressing Machine assembly.
Resulting in the hub of the total beating value does not meet the requirements of many reasons, the first may occur in the manufacturing process due to the error caused by processing for the field assembly, mainly due to correct the wheel hole surface treatment is not correct, so that the hub and axis concentricity deviation. Another reason is that there is a key Coupler Pressing Machine in the assembly, due to improper assembly of the key caused by the hub and the shaft different axis. The correct installation of the key should be the key side of the key and the keyway wall tightly fit, usually in the assembly with color inspection, with a bad time can be used to repair the file or blade to meet the requirements. Key upper part of the general gap, about 0.1-0.2mm or so. High-speed rotating machinery for the hub and the axis of the coaxial degree of high demand, with a single bond can not get a high degree of coaxial, with double bond or spline connection can make the coaxial degree of both improved.