Springs are used everywhere in the world around us and whether they’re used for clamping, buffering, or measuring, they are required to fit an exacting purpose in design.
While most appliances and pieces of equipment have a detailed specification for the type of spring used for any given purpose, sometimes there are exceptions to the rule, such as bespoke equipment which requires a part that is not exactly fitting of any pre-defined standard.
Before you can choose which customizations are the best for your needs, you need to understand what already exists on the market and therefore, what part of the design you’re able to customize.
A Classic Design with a Twist
A coiled spring is essentially a piece of elastic material that holds stored energy, the design of which is an instantly recognizable classic in the engineering world. The basic premise of a coiled metal wire can be enhanced by using shaped or stranded wires, which are then coiled to form the structure of the spring and in doing so, this can enhance certain properties within the design.
Coiled springs can be shaped in their design to fit a purpose, such as tapered and conical springs that are suitable for situations requiring a small clearance between two opposing surfaces as their telescoping property. This provides a reduced axial height in comparison to a regular compression spring. Alternatively, the wire itself that is used to form the coil can also be shaped to embellish the mechanical attributes.
Twisted and stranded wire is commonly used to create springs that require additional strength and durability in performance, especially for applications that involve a high amount of repetition. The woven nature of this wire allows the material to endure more stress than a similar, single-thread wire and also provides an extra layer of durability. This is highlighted in the way that the spring can suffer fractures to its structural integrity and still perform it’s role, making it highly suitable for tasks that involve heightened levels of fatigue where performance is essential.
Flat Wire Springs
The use of flattened wire to form the coil of a spring has some distinct advantages over the rounded wire that is typically used. Some of the advantages of flat wires springs include the following:
Strength
The main reason for its choice is due to the increased strength that this particular design provides. A flat wire spring can store more energy and so is suitable for tasks that require the spring to handle higher impact loads.
Length
The fact that they can operate with a reduced spring length in comparison to a round-wire spring of equal strength is also a major factor, especially for applications where space saving issues are of prime concern.
Sturdiness
Arguably the biggest appeal of flat wire springs lies in the increased sturdiness of this design. With a larger surface area across the horizontal axis of the spring, they naturally distribute the impact of a load more evenly and with less pressure. They’re also more resistant to warping and breakages due to the method of producing them that does not involve the wire being either stretched or compressed, processes which serve to weaken the physical property of the material.
All of these factors contribute to flat wire springs having a more robust design. It provides a longer lifespan and a more reliable product than the traditional round wire varieties that makes them a preferred choice for engineers looking for heavy duty solutions.
Variations in Design
Similar to any other type of compression spring, the design of the coil can be manipulated to provide varying qualities and performance adjustors.
Wave Spring
Wave springs offer a more rugged structure that helps prevent failure through torsional fatigue, the single main reason for a spring to break.
Again, these flat wire springs carry the advantage of being able to operate a heavy load within confined spaces. Furthermore, they direct the applied force in a controlled direction because of the engineered waves in the design. This works to reduce the torsional force placed on the spring in operation, which in effect reduces the amount of wear experienced by the spring.
Die Spring
Another common form of flat wire spring is the die spring. These designs are named because of their prominent use in the field of injection molding and were used to separate the plates used in the mold. They became the preferred choice in the industry as they are hard-wearing, reliable, and of simple design, whilst their use protected the mold cavities from being damaged by the ejector pins.
Customization Options
Effectively, all aspects of the flat wire springs design can be tailored to fit your needs by a competent manufacturer. There is a range of variables that need to be accounted for in the design of any new part and springs are no different in this respect.
Due to a spring being a simple mechanical instrument in its basic form, all variables will impact upon the performance and so any alterations to a design require careful calculation to craft a component that delivers the required output.
Some of these variables have only a small impact upon performance, such as the type of connectors chosen to attach the spring in place within the surrounding equipment, others like the material used to construct the spring will be of much more consequence to performance. Other variables that can be altered in the creation of the spring includes, but is not limited to:
- Coatings and finishes
- Wire dimensions
- Spring length
- Coil length
- Coil diameter
- Angle of the coil
With each of these affecting the flat wire springs deflection capabilities and tolerance levels, a detailed calculation is required in crafting a spring design based on the mathematical principles of the physics in motion.
Calculating the Load
One of the main parameters that is used to control the measured output of the spring is the thickness of the wire used in its construction. This, along with the type of material used, heavily affects the final performance level and is a quality which flat wire springs can be more easily altered in comparison to rounded-wire springs.
As there is also a variable in the shape and dimension of the wire’s cross-section, the wire itself can be sculpted to a degree that fine-tunes the output that the spring delivers. With more material used in the make-up of a flat-spring than a round spring of similar length, there is more material for an engineer to manipulate in achieving the desired product.
While there are online tools that can help with this, an exacting precision can only be achieved through an expert in the field of spring design who is trained in the nuances and practicalities of this field which experience can further complement. Coupled with the ability to produce the part to the specified standards that the theory projects of the outcome, the difference between a specialized manufacturer and a cheap producer can be more critical to the reliability of the design than any other factor mentioned above.