How Do I Choose The Appropriate Gearbox Type?

The selection of a gearbox is not always an easy task. For the purpose of managing dynamic motion, a gearbox may be utilized in the motion control and servo sectors; however, it may also be required in the power transmission sector in order to deal with overhung loads. Customers have access to a wide selection of suitable gearboxes from which they can choose the one that best meets their needs. If you make the wrong choice, it could mean having to spend more money on a more expensive gearbox.

When it comes to size, one of the first causes of contention involves the disparity in sizing between the load and the motor. Even if it might be simpler to size the motor to the gearbox and still produce a transmission that works, doing so will necessitate purchasing a gearbox that is larger than what is required. This is the case even though doing so might be simpler. In addition, the planned application does not fully utilize the capabilities of this gearbox. However, customizing the gearbox to the load ensures that it is suitable for the task at hand, makes it more cost-effective, and may even reduce the amount of space it needs to occupy.

The Frequently Used Components Of Sizing Applications

There are numerous aspects of gearbox sizing that are universally applicable. These criteria will be covered in detail and with insight in this section.

1. Service Elements

The service factor is typically described as the difference between the required value of an application and the rated value of the unit. The customer must first identify the service factor before scaling an application. A reevaluation of the service factor is necessary due to the presence of higher ambient temperatures, an unequal distribution of the load, and service hours.

2. The Outside Temperature And The Surrounding Circumstances

Because a rise in internal pressure is brought on by greater outside temperatures, it is necessary to make use of a higher service factor. In temperatures that are either exceedingly high or extremely low, it is possible that different types of sealing materials and lubricant viscosities will be required. The operating environment of the gearbox is yet another crucial aspect to consider when determining its size. The presence of unfavorable conditions may make the unit more susceptible to taking damage. In order to prevent corrosion or the growth of germs, it is sometimes necessary to make use of certain materials in settings that are dusty or dirty.

For the food and beverage processing industries, having oils and coatings that comply with FDA standards is absolutely necessary. In vacuum conditions, there won't be any air to cool, therefore ensuring proper grease and heat dissipation will require more planning and attention. If these environmental characteristics are not taken into account when designing the gearbox, it is possible that it will not be able to support the application in the correct manner. When determining the size of a gearbox, it is essential to take into account each of these aspects.

3. Shock Or Type Of Load

When subjected to strong shock and impact loads, the shaft bearings and gear teeth may experience accelerated wear. If this wear is not taken into consideration when the size is being determined, it could result in an early failure. In order to accommodate these additional load requirements, the service factor will need to be increased. During the application, non-uniform loads experience fluctuations, whereas uniform loads are maintained at a steady level. Even in situations when the load is relatively light, non-uniform loads call for a service component of a higher magnitude than uniform loads. One example of a load that is considered to be uniform is one that is carried by a conveyor that always moves the same number of things. An uneven load would be considered to be any kind of uneven application of cutting because of how it affects the work. The unequal cutting force results in the production of an imbalanced load, which in turn causes the torque that is supplied to the gearbox to occasionally increase.

4. Mechanism Or Style Of Output

Among the many varieties of output devices are the toothed pinion, the pulley, and the sprocket. Different output designs, such as a high number of output shafts or shaft-mounted bushings, each contribute to a reduction in the rated overhung load of the unit. It is imperative that the variable shaft loads that are imposed on the shaft by the various output systems be taken into consideration. While the vast majority of mechanisms produce a significant amount of radial stress, some, like helical gearing, are also capable of producing axial strain. In order to accommodate the additional radial or axial load, these outputs might need to have separate bearings installed.

5. Dimensions Of The Hollow Bore And Output Shaft

In order to properly size the application, it is necessary to take into consideration the output shaft and bore sizes that have been supplied by the customer. These may include the fact that the output of the unit is stainless, that it has both a keyed and keyless shaft, that it has both a keyed and keyless hollow bore, or that it has a flanged output in addition to any of the features listed above. In order to achieve the necessary bore size for a unit, the customer may need to purchase a gearbox that is either larger than the one they now have or of a different type entirely in order for it to suit their current shaft. It's possible that the customer will be able to switch out their shaft for the component that's the least expensive but still delivers an excellent solution in certain scenarios.

6. Types Of Homes

When selecting a gearbox, it is also necessary to give careful consideration to the location in which it will be installed. Tapped holes on many sides of a device, an output flange, or mounting feet are all possible features of a device. If you choose a different housing type, you might be able to save money by avoiding the purchase of specialized frames or brackets. This is because some housing types limit the positions in which a device can be used. For instance, the bottom face of the unit features tapped holes, which removes the requirement for a particular L-bracket to be placed around the output of the device.

Important Things To Consider When Transmitting Power  

Certain industry-specific factors influence the sizing process. The application calculations in the power transmission industry are influenced by the output RPM, motor horsepower, frame size, and overhung load.

Rpm Output

The working ratio of the gearbox or the input/output speed and operational hertz (Hz) must be computed by the client. An input of 1450 RPM at 50 Hz is the industry norm. Any changes must be mentioned during the size process because they have an impact on the ratio computation; if changes are not taken into consideration, the gearbox won't satisfy the needs of the customer.

Power And Dimensions Of The Motor

It is necessary to specify the gearbox size and input selection before figuring out the service factor. The required horsepower is used to determine the actual service factor after the gearbox has been sized. Heat produced by large horsepower motors could negatively impact the reducer's mechanical ratings. This lower rating—known as a reducer's thermal capacity—must be considered when using large motors because of the increased heat produced.

Overall Shaft Weight

Sizing must guarantee that the gearbox is not harmed by the load. The Overhung Load rating is the force (in Newtons) that the output shaft is capable of withstanding. The speed reducer will be harmed if its rating is significantly lower than the application.

Resulting  

Customers ought to size their gearboxes according to the weight. This will ensure that they get an application-appropriate, reasonably priced solution. The service factor, environment, temperature, shock load, output type, and service hours are all taken into account while sizing. Therefore, it is best to take all of these into account when choosing the best kind of gearbox for your needs.