Comprised of a simplistic beauty, springs may seem like a basic component but they are a design that is fundamental to many engineering solutions.
Tension springs provide resistance to a pulling force in a linear direction and can be used for storing potential energy or to create a resistance against a directional force. This is particularly useful for a number of reasons to engineers, whether in the pharmaceutical, energy, manufacturing, or agriculture sector. However, to create a component capable of delivering a precise result under certain conditions, many factors must be taken into consideration.
Precision Engineering
There are several variables to consider in the design and manufacture of any type of spring, especially when creating custom designs that will be placed under extreme operating conditions. This includes aspects connected to their physical shape and size as well as the properties inherent within the design, such as the initial tension or the total load threshold.
This is all further complicated by the often extreme environmental conditions which they’re required to work under. When this is the case, the performance calculations have to be carefully calibrated according to the altered physical traits the the spring material will experience under these conditions. This also needs to be used to determine their expected life cycle, as increased levels of stress will increase the rate of fatigue and can often dramatically impact the duration of time that they can be guaranteed to operate at peak effectiveness.
However, understanding the nuances of a tension springs role can often take the focus away from its principal purpose. Therefore, it’s always worth reviewing the primary function that a tension spring provides, to clarify what it is exactly they offer.
Controlling Movement
The most commonly perceived use of any type of spring is in controlling a lateral movement, such as the opening and closing of a cover or a door. Tension springs can be used to both trigger an opening or closing movement or to cushion such an action caused by an independent force.
Hooke’s law defines that the amount of force exerted is directly proportional to the distance the coil moves. Because of this, the spring can easily be designed in such a way as to provide the correct level of force over a specific distance to fit the overarching need of the system. It’s also essential to operate a spring well within its performance parameters to prevent too much stress being placed on the component through routine operations.
The fact that a spring stores energy rather than deflect it means that the forces in operation always need to be considered. It is this principle that effectively creates the bouncing effect associated with springs. And while this can be useful for some applications, a strong control over a system’s moving parts requires this to be counteracted.
Taking Accurate Measurements
Another common use for the extension spring is in measuring the size of forces in action within a system. There are two main ways in which a tension spring can be used to measure these active forces, and they are:
- The springs can be engineered to produce a specific amount of pulling force at a given rate of extension.
- The distance which the spring is extended can be used to calculate the amount of force being applied to it.
Any tension springs used in these ways require frequent calibration checks to ensure that the spring continues to operate within pre-defined parameters suitable to its application. While both of these measurements can be finely-tuned to produce finite degrees of accuracy, the smaller the margin of error, the more maintenance the spring will need.
There are numerous nondestructive methods used to force test a spring but one common oversight by companies is to neglect to test the calibration equipment itself. Therefore, it’s considered best practice to use more than one type of test to authenticate the results of the equipment against each other.
Specialist Equipment
Beyond movement and measurement, extension springs also offer several other features that can be exploited by engineers. A spring’s ability to store energy makes it ideal to use as a dampener to absorb vibrations. Tension springs can, therefore, also be used to lock a specific mechanical part into a fixed position similar to how locking pliers operate. This is also similar to the workings of a diaphragm valve that uses several tension springs in unison to control an aperture relative to the size of the force acting upon it.
Circuit breakers and switches can also utilize tension spring technology. A key advantage of using a spring for this task is they don’t require any external power and, therefore, are not reliant upon any external forces which may become limited in some emergency situations.
There are also many uses for the tension spring within the field of medical devices, with modern technology allowing springs to be created which offer both extremely small and extremely precise levels of performance. As the requirements placed on any type of spring increases, so too does the level of professionalism in the manufacturing of these components.
Robust Design
As with any equipment used for industrial applications, durability is imperative to creating a product that is both financially viable and reliable in a practical setting. Extension springs typically excel in this area, offering a notable level of reliability due to their fundamental structure, however, they can only perform to the standards in which they’re produced.
With springs being quick and cheap to produce, it can be tempting to select a supplier based entirely on price. A competitive marketplace means there is a wide choice of suppliers and manufacturers offering their products. However, not all suppliers provide parts of the highest quality despite their claims to the contrary.
By choosing an industry expert to provide tension springs for your engineering needs, there could be a small increase in price compared to other suppliers, but you will be paying for the hidden costs such as capability studies, premium materials and cutting edge manufacturing techniques. It’s also useful to remind yourself that in modern engineering, precision and reliability carry a much greater value than the small savings that can be achieved through compromising quality.