Over the past few years, manufacturers have put in a lot of technical expertise and huge sums of money in developing leading edge products delivering much greater levels of precision and performance. The gearbox is one of the earliest transmission tools created by man, the fundamental purpose of which has not changed since its inception – to transmit coordinated motion at a constant ratio between shafts.
For any given application, several factors influence the selection of a gearbox. Some of the basic factors that have to be considered include torque (continuous torque, braking torque, acceleration torque, and repetitive peak torque), power, speed, and ratio. There are also other features that greatly impact gearbox selection and those include mounting arrangements, smoothness of transmission, efficiency, shaft alignment, backlash, size, noise, weight, maintenance requirements, and operating lifespan.
Among all these factors, size is the major one that needs careful consideration. Here are a few tips on gearbox sizing selection.
First of all, when it comes to deciding on the size of gearbox you need, you need to be aware of your application’s performance requirements. Few examples of these requirements include:
- Torque – refers to the torque load requirement for your application.
- Speed – the turning speed of the output shaft as required by your application.
- Life – how many continuous hours are needed to match the desired life?
- Duty cycle – how long is the gearbox capable of operating before turning off?
This is yet another factor that influences the size of the gearbox you need. You need to determine if the overall efficiency of the gearbox needs to be below a specific value when it is coupled with a motor. Generally, the torque range of gearboxes enables them to operate at maximum efficiency. Therefore, if the gearbox has larger gears than what is actually needed, its efficiency will drop down considerably.
The location of the application can also influence the sizing of gearbox.
- Space – do you need the gearbox to fit in a confined area?
- Operating temperature – determine whether the temperature at which the gearbox will be operated will remain the same or have huge variations.
- Weight – should the weight of the gearbox fall within a certain amount?
The cost of the gearbox is certainly one major factor that influences your purchase decision. Cost varies depending on the material you choose. Some of the most commonly used materials are as follows:
- Bronze – gears made of bronze are usually used in worm gear sets, and this depends entirely on the application. Based on the level of performance you need, the size of worm gears will differ.
- Powdered metal – this is one of the low cost solutions. In this process, metal will be ground, and the powder will be contracted in a die before use. However, gears made of this material are known to have reduced load carrying capacity and hence may not be suitable for certain applications.
Machining steel and plastic are two other materials available. You can choose one based on your needs and the application for which you need the gearbox. In order to make sure that the gear you choose is of the best quality and delivers optimal performance, it is important that you choose a reputed supplier or dealer.