Editorial by Industrial Quick Search

Compression Springs

Contact Companies

Please fill out the following form to submit a Request for Quote to any of the following companies listed on


Get Your Company Listed on this Power Page


Introduction

This article will take an in-depth look at compression springs.

The article will look at topics such as:

  • Principle of Compression Springs
  • Manufacturing Processes and Materials Used to Make Compression Springs
  • Types of Compression Springs
  • Applications and Advantages of Compression Springs
  • Common Problems in Compression Springs
  • And much more…
Compression Springs

Chapter 1: Principle of Compression Springs

This chapter will discuss what compression springs are and the considerations when choosing compression springs.

What are Compression Springs?

Coil springs called compression springs can store mechanical energy when they are compressed. These open-coiled, helical springs provide resistance to compressive loading. When these springs are subjected to a compression load, they compress, grow shorter, and absorb a large amount of potential force.

Compression Springs

The springs are forced back to their original lengths and forms after the load is reduced or eliminated by the stored energy. When weighted, compression springs become more compact. In contrast to extension springs, compression springs' spiral wires do not contact when they are relaxed; instead, when stressed, they are tightly compressed.

Considerations When Choosing Compression Springs

The are various considerations when choosing compression springs which include:

Compression Spring End Considerations

Compression spring end types might be normal or customized. Standard ends can be open or closed, or they can be ground or not. Given the same number of coils, wire size, and outside diameter (OD), open or closed ends will alter the spring rate.

Compression Spring Ends

However, when combined with closed ends, this characteristic will enhance the squareness of the loading force and lessen spring buckling tendencies. Ground ends demand additional manufacturing work.

Certain manufacturers, while not all, offer closed and ground ends in their regular catalog stock designs; this is an important distinction to understand. Examples of special ends include expanded coils to snap into ring grooves, offset legs to serve as alignment pins, and decreased coils for screw attachment.

Outer Diameter of Spring

Compression Spring Material Considerations

Carbon steel and exotic alloys are only a few possible spring materials. The most popular material is music wire, a high carbon spring steel. Stainless steel 302 improves overall corrosion resistance but is less strong than music wire.

Nickel alloys are chosen for their extreme high or low operating temperatures, specialized corrosive conditions, and non-magnetic properties. They are labeled under a variety of trademarks. In addition, copper alloys with superior electrical conductivity and corrosion resistance include phosphor bronze and beryllium copper.

Compression Spring Physical Considerations

Outer Diameter: If the compression spring is going into a hole, its outside diameter should be considered. In any case, if any internal components of the device will surround the spring, those must also be measured. A spring's outer diameter (OD) will enlarge when it is compressed, which is also important to consider if the spring will be used in a tube or a bore.

The outside diameter of springs is also subject to manufacturing limitations, which can increase the assembly's needed envelope size. Most spring manufacturers will specify a work-in-hole diameter for a spring based on projected OD expansion and manufacturing tolerance. Use this information to more effectively express the product needs when obtaining custom-made springs or to easily choose from stock spring catalogs.

Inner Diameter: If the compression spring passes over a shaft or mandrel, the spring's inner diameter needs to be considered. To prevent friction, there must be a ten-thousandth of an inch between the shaft and the spring.

Compression Spring Inner Diameter

Free Length: To ensure that the compression spring is in a preloaded state and stays in position, it is advised that its free length be a little bit longer than the available space.

Compression Spring Free Length & Solid Height

Solid Height: The wire diameter and the total number of coils impact the solid height of the spring. Make sure the loaded height is not shorter or taller than the solid height.

The setting in which the spring will be used includes the temperature and additional components such as moisture. The more expensive the spring’s material, the higher the temperature a spring can withstand, but this will increase its cost.

Compression Spring Load Considerations

The compression spring's loading or travel needs to be considered as well. The relationship between the force needed to compress a spring by a unit of length—typically pounds per inch (lbs/in)—is known as the spring rate or spring constant. The product designer can therefore determine projected spring travel with a particular load. The spring is put under increasing strain as it is driven further. The substance of the wire may eventually give way under stress, leading to a phenomenon known as spring set. The spring won't re-expand to its initial unloaded length once it has been set. Nevertheless, depending on the assembly, this spring may be useful.

Chapter 2: Manufacturing Processes and Materials Used to Make Compression Springs

This chapter will discuss the manufacturing processes used in making compression springs and the materials used.

Compression Springs Manufacturing Processes

The manufacturing processes used in making compression springs include:

Coiling

Coiling first feeds the wire through a process of straightening. The coiler will generate better parts if the wire is straighter when it enters the coiler. During this step, CNC machinery with preprogrammed settings modifies the arms and arbores to produce the spring, adjusting factors including the spring's free length, pitch, and coils. A high-speed camera records images as the machines create the spring, allowing us to measure each component and make adjustments as necessary to keep it within tolerance. The product then moves on to the process of alleviating stress after the machine cuts the spring from its wire.

Coiled Compression Springs

Stress Relieving

The substance of the wire is stressed during the coiling process, which makes it brittle. We fix this by heating the spring in an oven, which causes the coil to solidify in its new shape and generate metallic links. For a predetermined period, the oven maintains the temperature of the coil of wire at the proper level before slowly allowing the coil to cool.

Finishing

Depending on its intended application, the wire is treated to a number of finishing operations once it has gone through the stress-relieving process. Completing a spring converts it from its initial form into a specific tool that will enhance its potential applications. The following are a few of the procedures involved in spring finishing:

  • Grinding: Designers must grind the spring's ends flat, enabling them to adhere to other surfaces more readily.
  • Strength peening: Strength peening prevents metal fatigue and fractures in steel despite heavy use and frequent flexing.
  • Setting: Designers thoroughly compress the spring so that all of its coils touch in order to establish its intended length and pitch permanently.
  • Coating: Designers can coat the spring with non-corrosive paint, submerge it in liquid rubber, or plate it with another metal, such as zinc or chromium, to avoid corrosion.
  • Packaging: Designers develop specialized spring packagings, such as bulk packaging in boxes or plastic bags.

Materials Used to Make Compression Springs

Steel materials that can be used to make compression springs include stainless steel, hard-drawn steel, steel music wire, and spring steel. Compression springs with wider wire diameters may sustain more forceful use than springs with smaller wire diameters. In general, the larger the wire, the stronger the spring. Decreases in the coil diameter of the spring can also increase its strength.

Due to its resistance to corrosion even when frequently exposed to moisture and chemicals, stainless steel is a strong choice for these applications. Steel is resilient and sturdy; it can endure continuous use without breaking.

In addition to spring steel, other types of steel and even plastic can be used to make springs. However, incorrectly matching a spring with its application can result in early failure, which can cause damage to nearby items and, in certain situations, injury to humans.

Compression Spring

It is crucial to choose the right material for spring composition. Choosing a spring properly will maximize its efficacy and lifespan. For spring materials, steel alloys are typically employed. Low carbon, high carbon, stainless steel, chrome silicon, and chrome vanadium alloys are common alloys. Some metals, such as titanium, phosphor bronze, and beryllium copper alloy, are employed occasionally as springs. Ceramic materials are used for coiled springs used in high-temperature environments.

Due to its high carbon steel composition, music wire can be utilized for high-intensity applications, including gym equipment, lawn and garden tools, and home improvement items. Strings made of music wire have elasticity moduli of 30,000 psi and minimum tensile strengths of 230-399 psi.

The springs typically found in commercial products like pens, office supplies, toys, and other indoor-use items are made of hard-drawn wire, a medium carbon steel. These springs can be specifically adapted to various applications because of their wide range of hardness, with Rockwell hardnesses ranging from C31 to C52.

Characteristics of Compression Spring Material

  • Cold-drawn, hard-drawn wire is the least expensive spring steel, typically employed for static loads and low stresses. The material is not suited for temperatures below zero or more than 2192 °F (1200 °C).
  • Cold-drawn, quenched, tempered, and all-purpose spring steel is known as oil-tempered wire. However, it is not appropriate for unexpected loads, exhaustion, or temperatures below zero or above 3272 °F (1800 °C). Alloy steels are useful when we opt for severely stressed circumstances.
  • Chrome Vanadium: is an alloy spring steel that can withstand high temperatures and stresses of up to 3992 °F (2200 °C). It has strong fatigue resistance and long shock and impact load endurance.
  • Chrome Silicon can be used to make springs under a lot of stress. It provides outstanding performance for long life, shock loading, and temperatures up to 4532 °F (2500 °C).
  • Music wire is most frequently employed in small springs. It can endure repeated loading at high pressures and is the toughest material with the highest tensile strength. It cannot be utilized at temperatures below zero or above 2192 °F (1200 °C). Music wire is typically a popular choice for springs.
  • Widely utilized alloy spring materials include stainless steel.
  • Brass and phosphor bronze springs both have good electrical conductivity and corrosion resistance. They are utilized frequently for contacts in electrical switches. Brass springs can be used in extremely cold temperatures.

Leading Manufacturers and Suppliers

GET YOUR COMPANY LISTED ABOVE

Chapter 3: Types of Compression Springs

Different types of compression springs include:

Convex Compression Springs

Convex springs, also known as barrel-shaped springs, feature coils with larger diameters in the center and coils with smaller diameters at either end. When the springs are squeezed, their designs enable the coils to fit inside one another. A compression spring with the top and bottom outer diameters smaller than the center outer diameter is known as a convex spring. Convex springs are used to generate linear force.

Barrel Spring

Barrel springs can be produced in a wide range of diameters, allowing for an infinite number of designs. Because it may save space, eliminate buckling, and come in various shapes to better fit any designs, a barrel spring is preferred by end users over a generic compression spring. Telescoping or non-telescoping barrel springs are both possible. Manufacturers use convex springs in applications where more stability and movement resistance are needed when the springs deflate. They are mostly used in the toy, furniture, and automobile industries.

Conical Compression Springs

Conical springs are cone-shaped tapering springs. One end of the spring has a diameter greater than the other, and the coils all around the spring give a progressive taper or form shift. Some conical springs have diameter variations between coils that allow each coil to fit the one before it. These springs tend to increase stability while lowering the solid height. Some cone springs have their diameters adjusted to the point where, because of their tapered cone shape, they will exhibit a telescope effect when compressed. This allows the user to fully compress the spring, causing all of the coils to collapse inside of one wire diameter, giving more travel or deflection. This is the best option if the product's creator requires a greater deflection or travel distance.

Conical Spring

Conical springs are superior to standard compression springs in terms of stability. Since the larger outer diameter of tapered springs is typically on the bottom, they provide better stability, are less likely to buckle, and do not lose their balance when compressed.

Disc Springs or Belleville Springs

The following image depicts the coned disk that makes up a Belleville spring. Julian Belleville created it and registered its design in France in 1867. The image below depicts the typical load-deflection characteristics of a Belleville spring. There are many different load-deflection curves available due to the difference in the (h/t) ratio. Plate clutches, brakes, relief valves, and a wide range of fastened connections require Belleville springs.

Belleville Spring

These are the benefits of Belleville springs:

  • It is easy to manufacture and has a straightforward construction.
  • It is a small spring assembly.
  • It is particularly helpful when a very strong force is required to deflect a small spring.
  • It is adaptable since it offers a wide range of spring constants.
  • Any linear or non-linear load-deflection characteristic can be provided by it.
  • Coned disks can be stacked in series, parallel, or series-parallel configurations depending on their size and thickness. Without altering the design, these combinations offer a variety of spring constants.
  • Double deflection for the same force is achieved by series-connecting two Belleville springs. On the other hand, when two Belleville springs are connected in parallel, the force for a given deflection is approximately doubled.

Concave Springs

Concave springs, also known as hourglass springs, have a coil that is narrower in the center than it is at either end. The springs' symmetrical shape contributes to keeping them centered at a specific location. A concave spring saves space, eliminates buckling, and benefits numerous specialized places with its design distribution. The end coils of a concave spring are wider than the center coils; therefore, the pressure is distributed unevenly, improving stability. There are more alternatives because there are numerous different configurations to select from that may be included in any design.

Concave Springs

Straight Coil Springs

Each coil of a straight spring has the same diameter. Some of the most popular springs used are those with straight coils.

Straight Coil Spring

Volute Springs

A volute spring has cone-shaped coils rather than wire with a round, oval, or square cross-section. Similar to a conical compression spring, they operate similarly. The cone shapes slide over one another rather than being forced together by compressive force. Compared to a non-conical compression spring of the same length, a volute spring will compress down to a lower solid height.

Volute Spring

Variable Pitch Spring

The coils in variable pitch springs are spaced more widely in some places and closer together in others. Pitch is the term for the distance between adjacent coils of wire. Variable pitch springs have different intervals between each coil along the length of the spring.

Variable Pitch and Constant Pitch Springs

Magazine Springs

To drive cartridges or bullets into the chamber of a handgun, magazines use compression springs with oval or rectangular coils. These springs need to be manufactured with extreme accuracy and strict quality control. There are many different spring design options available, with variations in length, coil count, and required force. Since most magazine springs operate close to their solid height, rate becomes a crucial design consideration.

Magazine Springs

Torsional Springs

A torsion spring is a mechanical tool that stores and releases rotational energy. The torsion spring is attached to a mechanical part at each end. The winding of the spring is tightened and stores potential energy when it is turned around its axis at one end. As the other end is kept fixed, it is deflected about the body's centerline axis. The spring stores more potential energy as the winding becomes tighter and resists more rotating force. The spring will unwind as it performs an elastic rebound after being released, releasing the tensioned energy.

The opposing end of the spring experiences an equal rotating force, which might impart torque on the attached mechanical component. Mechanical parts can be statically held in place by torsion springs. As the spring is twisted to create a tighter winding, it is more susceptible to bending stress than rotational stress.

Unlike compression and tension springs, which are affected by linear and rotational forces, these springs are different because only rotating force is involved. To return to their original winding after being twisted, they also rely on the material's elasticity.

Depending on the direction of rotation, tension springs can exert force either clockwise or counterclockwise. To provide the most force, a torsion spring must be turned in the direction of the winding.

There are several uses for torsion springs in practically every industry and numerous variations of these springs.

Torsion Spring

Chapter 4: Applications and Advantages of Compression Springs

This chapter will discuss the applications and benefits of compression springs.

Applications of Compression Springs

The applications of compression springs include:

  • Automobiles: Without at least some compression springs, it would be very difficult to manufacture most cars. Compression springs are used in automobiles in various places, such as the seats, the hoses, and even the suspension. The seats employ compression springs to conform to the body and provide more comfort. To satisfy the wide variety of vehicle compression spring uses, a variety of sizes and shapes are naturally available.
  • Door locks:Traditionally, springs have been essential to the proper function of door locks. Most metal locks contain some steel spring due to the mechanism of a lock and key system, which relies on the key to release the pressure holding the bolt in place and maintaining the door's lock. A spring generates that tension. Since the 1700s, compression locks have been used for this purpose by locksmiths.
  • Pens: A compression spring can be observed by examining a ballpoint pen. This spring enables the pen to write while exposing the tip and then shields the tip inside the housing to prevent the ink from drying out. This makes it possible to use pens without cumbersome and easily lost caps.
Pen Springs

  • Aeronautics: The majority of air travel would be impossible without numerous types of springs. The springs on a plane may not be visible, but air turbines, guidance systems, engine controls, wheels, brakes, meters, fuel cells, and diesel engines are just a few of the components in an airplane that require springs.
  • Firearms: Whenever considering tension, consider compression springs. Take into account the strain needed to fire a bow and arrow. The crossbow is a much simpler weapon if the human component is replaced with a compression spring. Technological advancements continue with the modern semi-automatic handgun, which uses a compression spring to absorb the energy produced by recoil and then redirect it to advance the slide or bolt and reload the weapon for the subsequent shot.
Firearm Spring

  • Medical devices: Mechanical compression springs are used in many medical device applications, from tiny springs found in inhalers, pill dispensers, and syringes to many diagnostic tools. Additionally, there are springs for various medical devices, including catheters, valves, peristaltic pumps, wheelchairs, endoscopic devices, staplers, and surgical, orthopedic, and other tools.

Advantages of Compression Springs

The advantages of compression springs include:

  • Preventing another component's movement: The capacity to stop another component from moving is one of compression springs' greatest advantages. Thanks to this feature, a minuscule compression spring is now an essential component of the gauge's internal design and operation. The gauge's media are pumped under pressure into a hollow tube, which seeks to straighten up as it fills. This pressure causes the tube to move, pushing a link and gear connected to the tiny compression spring. The pressure indicator needle's location is affected by the spring's resistance, pushing back, and resistance.
  • Putting a component back in the right position: Door latches on both automobiles and building doors are an additional advantage that demonstrates how frequently utilized and essential compression springs are. Imagine raising a handle to open a door to get the greatest understanding of how a spring operates. The lock mechanism's compression spring would restore it to the locked position if the motion was used without pulling the door open. The spring can be compressed by tugging or turning the device; if it retains its position, the spring will stay compressed; otherwise, it will latch once more.
Spring Latches

  • Applying continuous pressure: One of the most significant and amazing advantages of compression springs is in battery-operated products. Compression springs' continuous pressure completes the secure electronic contact needed for circuits inside all kinds of battery-operated gadgets. Think of the separate battery slots in a child's toy or flashlight. The small compression spring in each battery slot needs to be gently squeezed to accommodate the battery. In addition to holding the battery in place, the stored energy produced by this compression also establishes the conductive connection necessary for the device to draw power from the battery. Users might not be surprised by some of these advantages; in fact, users could be interested in compression springs because of one of them. Compression springs are undoubtedly the greatest option for applications of all sizes, across all industries, and millions of different uses because they provide a special mix of advantages.
  • Lightweight: Compression springs are remarkably lightweight, considering the amount of force they can produce. The spring is stronger thanks to the coiled steel than the metal would be if it kept its original straight shape. Heating and cooling also strengthen the metal, allowing for the use of less material to support heavier weights.
  • Affordable: Most compression springs are composed of steel and other affordable metals. These metals are readily available worldwide and are inexpensive. Compression springs are among the most cost-effective options for any usage since they contain minimal metal.
  • Maintenance-free: A compression spring requires no maintenance. The spring does not require lubrication, cleaning, special coatings, or other maintenance to function. The only issue with springs is that they could occasionally break. However, replacing a broken compression spring is a simple process.

Disadvantages of Compression Springs

The disadvantages of compression springs include:

  • Costly conical springs
  • Gets weaker if compressed over an extended period
  • Loses both stability and shape over time
  • Buckles when the axial load increases
  • Challenging to fix when broken

Chapter 5: Common Problems in Compression Springs

Common problems associated with compression springs include:

Surging in Springs

When one end of a helical spring is resting on a rigid support and the other end is suddenly loaded, the coils will not deflect uniformly because it takes time for the tension to propagate along the spring wire. The spring's end coils in touch with the applied load first absorb all of the deflection before transferring a significant portion of that deflection to the adjacent coils. A compression wave travels through the coils to the supported end before reflecting to the deflected end. This phenomenon can also be seen in a closed water body when a disturbance flows in one direction before returning to where it first appeared. This compression wave moves endlessly down the spring. Resonance will happen if the applied load is variable and the space between load applications is the same as the time needed for the wave to move from one end to the other. The coils experience extremely high strain and massive deflections as a result. The spring could just barely fail in these circumstances. This occurrence is called surge.

Surging Springs

The following techniques can be used to stop the springtime spring surge:

  • Equip the central coils with friction dampers to stop wave propagation
  • Use springs of high natural frequency (the operating frequency of the spring should be at least 15-20 times less than its fundamental frequency)
  • Vary natural frequencies by using springs with coil pitches towards the ends that differ from those in the middle.

Buckling in Springs

The spring behaves like a column and may fail by buckling at a relatively modest load when the free length of the spring (LF) is greater than four times the mean or pitch diameter (D), according to experimental findings. The following relation can be used to compute the critical axial load (Wcr) that results in buckling.

Buckling can be avoided by:

  • Making the free length (LF) less than four times the coil diameter (D)
  • Choosing a material with a higher degree of rigidity
  • Mounting the spring on a central rod or placing it in a tube to prevent spring buckling
  • Minimizing clearance between the tube walls and the spring while keeping it large enough to accommodate increase in spring diameter during compression
Buckling Spring vs Normal Spring

Conclusion

Compression springs can store mechanical energy when they are compressed. These open-coiled, helical springs provide resistance to compressive loading. When these springs are subjected to a compression load, they compress, grow shorter, and absorb a large amount of potential force. The springs are forced back to their original lengths and forms after the load is reduced or eliminated by the stored energy.

Thus, the selection of compression springs has to be made in consideration of the intended application, characteristics, benefits, and disadvantages of compression springs.

Leading Manufacturers and Suppliers

GET YOUR COMPANY LISTED ABOVE

Table of Contents

Principle of Compression Springs

Manufacturing Processes and Materials Used to Make Compression Springs

Types of Compression Springs

Applications and Advantages of Compression Springs

Common Problems in Compression Springs

Loading Leading
Category Companies:

  • IQS Homepage
  • All Articles
  • GET YOUR COMPANY LISTED

Related Posts

Coil Springs

Coil Springs

A coil spring is an elastic element made of metal or heavy plastic in the form of curls or ringlets of round wire or cord that is wrapped around a cylinder. The winding of a coil spring can be loose or tight in a helical shape depending on the application for which it is made...

Extension Springs

Extension Springs

Extension springs are helical wound springs that are so closely coiled together to create initial tension in the coils. This initial tension creates resistance against the force applied to its ends for extension. The initial tension helps determine how closely and...

Metal Springs

Metal Springs

Springs are a flexible machine element that store mechanical energy when subjected to tensile, compressive, bending, or torsional forces. When the spring is deflected, it stores energy and at the same time exerts an opposing force...

Torsion Springs

Torsion Springs

A torsion spring is a mechanical device that stores and releases rotational energy. Each end of the torsion spring is connected to a mechanical component. As the spring is rotated around its axis on one end, the winding of the spring is tightened and stores potential energy...

Contract Manufacturing

Contract Manufacturing

Contract manufacturing is a business model in which a company hires a contract manufacturer to produce its products or components of its products. It is a strategic action widely adopted by companies to save extensive resources and...

Wire Baskets

Wire Baskets

Wire baskets are made from a series of wires that are woven together or welded to form a shape of a basket. They can also be defined as containers that are made by use of an openwork pattern of metal...

Wire Displays

Wire Displays

Wire shaping is a complex method that encompasses a wide range of dimensions, forms, and textures. The technique of creating a usable product by wire bending and shaping is known as custom wire forms...

Wire Forming

Wire Forming

Wire forming is a method for applying force to change the contour of wire by bending, swaging, piercing, chamfering, shearing, or other techniques. The various techniques for wire forming can produce any type of shape, form, or configuration...

Wire Racks

Wire Racks

A wire rack is a level wire form utilized to stock and exhibit a number of products, usually retail. The bottom surface on which such goods are stored is made of several latticed or interlaced metal strands...

© IQS Directory . All Rights Reserved.