There are several criteria on how to find the right spring materials and they can make or break your quest to choose high-quality compression springs for your machine. Here’s what you should know.
The various types of springs on the market may only be small devices, but they can greatly impact on the proper functioning of your equipment.
These springs can also be used in vehicles and engineering tools (such as Heavy-duty bench vice) and as such, they are built differently to support the device in which they will find an application. Moreover, they are typically excellent for handling heavy loads because of their high tension and compression properties.
For these reasons, it becomes needful to outline the spring material properties which should be your utmost consideration as a manufacturer or consumer.
Likewise, the spring materials that are commonly used have been reviewed in a bid to narrow down to what other manufacturers are taking advantage of and what may have brought about their sudden interest in it.
What is a Compressor Spring?
A compressor spring stores or releases kinetic energy by either resisting or facilitating the movement of mechanical parts of a machine.
Consequently, you can find many types of springs:
- Compressor springs
- Extension springs
- Torsion springs
- Die springs
- Wire forms
- Custom springs
How to Determine the Right Spring Materials?
To determine the right spring material for your machine, you need to know their characteristics and also put certain factors into consideration.
Having a good knowledge about them will ensure that you get it right the first time and take away the need to replace parts even before they have long served their purpose.
It can, therefore, save you the time, effort, and money that will be required to replace deteriorated parts.
Now, consider the following while being on the lookout for the right spring materials to settle on:
- Operating environment of the spring
- Stock or custom-made spring
- Customization process of the spring
- OEM Standards and RoHS Compliant
- Spring size
1. Operating Environment of the Spring:
The best spring material selection guide is one that outlines the necessity to be on the lookout for the environment where the spring or wire of your compressor will be used.
That being the case, the surrounding space (indoors or outdoors) of your machine needs to be given utmost consideration before finally choosing spring materials that will serve its intended purpose. You’ll find springs made up of:
- MP35
- Elgiloy
- Inconel
- Music Wire
- Nimonic 90
- Stainless steel
- Chrome silicon
- Beryllium copper
- Phosphor bronze
Let’s take a closer look at some of these general spring material:
a. Stainless Steel:
A spring steel material property include its high resistance to corrosion, excellent fatigue properties, good formability, high strength and hardness, and minimal distortion upon being treated with heat.
Generally, high-grade stainless steel will be more temperature resistant even though more load being put on the spring can decrease its resistivity.
b. Inconel:
Inconel is a Nickel-Chromium alloy which has found a use case in environments with high temperatures.
This material is resistant to oxidation and corrosion and it can also be used in extreme conditions.
c. Nimonic:
In comparison to Inconel, Nimonic 90, a Nickel-Chromium-Cobalt alloy can be used in high-temperature applications and it is corrosion resistance.
However, the level of strength required from such wires is higher than that of Inconel which makes Nimonic more suitable in this case.
d. Hastelloy:
One more material that is used in the production of springs for compressors is Hastelloy, a Nickel-Molybdenum-Chromium alloy.
This material may be more resistant to pitting and crevice corrosion than Inconel and Nimonic, but its strength is questionable in comparison with the duo.
Consequently, each of these spring materials strives to serve the same purpose even though some can withstand certain temperatures more than others which gives them prolonged strength.
It can, therefore, be said that their level of performance is not entirely the same.
e. Other Environmental Factors:
Thus, you must decide if the spring will be immersed in water, used under high temperatures, or in corrosive environments which could bring about its failure due to a gradual loss of its structural integrity.
Corrosion, for instance, can be caused by exposure to chemicals and condensation and it can be mitigated by choosing a spring that has a protecting finishing on its exterior.
It will ensure that whether the machine is kept indoor or outdoor, it does not degrade easily.
2. Stock or Custom-Made Springs:
Your choice of a stock spring over a custom made one and vice versa will be determined by the cost and how fast you want the spring.
- Accordingly, stock or off-the-shelf springs have already been designed hence, all that is required is to find one in the right material, size, weight and can meet the demands of your machine.
- Custom-made springs, on the contrary, ensure that the spring is designed by an engineer to meet your specifications.
You can narrow it down to the cost, material, size, weight, among other factors that will ensure that the spring is the best fit for your equipment.
The downside, in this case, is the higher cost and more time it’ll take to see each of these delivered.
3. Customization Process of the Spring:
Now, a question you will need to ask is, “Has the spring material been designed properly with precise mechanical and strength calculations?”
While our focus is on the material the spring is made of, the customization process is also of importance.
In this case, if you have settled for a custom-made spring, then a great deal of consideration has to be given to how tough the spring is to ensure that it can withstand the stress it will undergo and handle its load efficiently.
In the same vein, the use of helical vibration isolators in medical types of equipment will also prevent vibrations from weakening the spring.
Each of these will need to be ascertained by a spring manufacturing innovator or mechanical engineer who is conversant with the spring design process, can create a spring that meets your needs, and one that can stand the test of time.
There will be a need to verify and validate the design parameters to ensure that the specs sheet of the custom spring to be made aligns with the resultant product.
On the same note, your best bet would be a spring that has been passivated or shot-peened to boost its level of endurance.
4. OEM Standards and RoHS Compliant:
Asides from the obvious reasons for choosing the best spring materials, one more that has to be given great thought is if it meets the Original Equipment Manufacturer (OEM) Standards as well as the Restriction of Hazardous Substance (RoHS).
OEM standards, for instance, ensure that the spring material is of the highest quality based on several conditions it has been susceptible to.
Some of these include:
- Stress relieving
- Heat treatment
- Metal plating
- Grinding
- Painting
- Magnetizing of the spring, amongst other options
RoHS, on the other hand, is a Directive 2002/95/EC from the European Union which restricts the use of hazardous substances such as mercury (Hg), lead (Pb), cadmium (Cd), polybrominated biphenyls (PBB), and hexavalent chromium (CrVI) in the production of electrical and electronic products.
These are substances that pollute the environment and are also harmful when exposed to the body during the manufacturing process.
5. Spring Size:
If you’ve gone through the trouble of determining the spring materials that are good enough to deliver an acceptable level of performance when used in your machine, you also need that the spring is in the right size depending on the use it will be put to.
Like the materials, a range of sizes have been provided. An example is that of the Hefty Die Springs which are manufactured with the use of shot-peened, round wires to give them additional strength.
The aim is to make them a heavy duty which, in turn, ensures that they can stand the test of time before there is finally a need for a replacement.
There are also springs whose size and weight have been specifically tailored for medical devices and industrial applications. As such, you should know beforehand the:
- Intended load
- Mounting location
- Length the spring will be stretched to
Calculating Size
Keep in mind that while it is good not to have a spring who size is considerably short, it is also useful to have one of a minimal length to prevent the object from overstretching itself and degrading easily.
You can also calculate your springs specification by using factors such as:
- Wire diameter
- Outer diameter
- Length of spring
- Number of total coils
The same applies to choose the right spring end and you’ll usually find the following:
- Open ends
- Double closed ends
- Closed and ground ends
- Closed and squared ends
Conclusion
Whether it’s your first time trying out springs for compressors, our guide on how to find the right spring materials will keep you informed on the best which the market has to offer.
Moreover, you can make the hard decision even in the face of a range of choices without choosing a material that will lead to wastage of effort, time, and resources.
The fact that these devices do not come cheap means that whichever you settle for must serve its purpose and for a long time before it degrades.