Compression Spring
Compression springs are the most popular of the springs produced. They are made by cold winding for elastic deformation at the place of their application.
Our production has launched the production of high-precision compression springs, manufactured in accordance with GOST, both with standard parameters (some are in stock) and non-standard characteristics (according to samples or drawings of customers).
Target calculations of the main parameters of springs take place on our spring calculator .
The scope of application of compression springs is very extensive and covers almost all areas of industry.
"Uralmetallresurs" carefully refers to the choice of materials and the manufacturing process of cylindrical compression springs.
Therefore, a special round spring steel with bar diameters corresponding to the current GOST and DIN is used.
Compression Spring Configurations
The configurations are the simplest.
Their purpose is to absorb and accumulate mechanical energy.
The gap between the turns (also called the pitch of the turns) is sufficient for elastic deformation and effective resistance to the applied load by the elastic element of the spring wire.
For uniformity of efforts along the axis of trimming of the supporting coils, the springs are manufactured in compliance with the following parameters of the working coils.
The type of spring depends on:
· diameter D of the rod used;
· number of turns;
· interturn pitch sizes;
· given diameter.
Features of the final coils of compression springs
The design of the end coils is of great importance for the correct operation of the compression springs. The shape of the end turns must meet the following conditions:
· the contact surface between the end coils and the supporting parts must be flat and perpendicular to the axis of the spring in order to avoid point application of the load;
· the contact area should, if possible, be a complete ring to avoid eccentric load application;
· the design of the end coils must ensure the correct centering of the spring and supporting parts.
Since the number of working coils determines the elastic characteristic of the spring, it is important to clearly distinguish between working and supporting coils.
A distinctive feature of the support coils is that the support coils do not move relative to the surfaces on which the spring rests. The support coils of the free end of the spring move together with the support plate, the support coils of the fixed end of the spring are stationary.
The boundary between the working and supporting coils is considered to be the point of contact of the coils in the free state of the spring.
The number of reference turns cannot be less than 1 if it is desired to avoid weakening the nearest working turn.
In practice, 1.5 reference turns are most often made on each side of the spring. For long springs and for springs subjected to cyclic loads, the number of support turns is adjusted to 2-2.5.
Spring stability
With a large length of the spring, there is a danger of loss of longitudinal stability, i.e., buckling of the spring to the side.
For springs with axial load, with well-directed centering elements that ensure the parallelism of the ends of the spring during the working stroke, the limiting ratio of the height L of the spring in a free state to the average diameter D of the spring, at which the spring still remains stable, is ≈5; for springs with hinged centering elements L/D = 2.5.
If, for structural reasons, the use of long springs cannot be excluded, special measures must be taken against loss of stability:
· extension of the centering bands to reduce the free span of the spring;
However, the introduction of an additional centering belt in the middle part of the spring is associated with increased friction and the risk of wear of the coils of the spring.
· divide long springs into several short stable springs, which should be based on floating centering elements well directed along the axis of the spring.
This method is associated with an increase in the overall length of the installation due to the introduction of additional support coils in the areas where the floating centering elements are located.
The characteristics of a compression spring are:
1. Wire section thickness.
2. Spring outside diameter.
3. Spring height.
4. Distance between coils of wire.
5. Working / total number of turns.
6. Preloaded / not preloaded extreme turns.
7. Ground / not ground end coils.
8. Winding direction - right / left.
9. Material, steel.
10. Operating temperature.
11. Work load.
How to measure compression springs
What are the main parameters to be measured or calculated:
· The diameter of the wire;
· outer diameter of the spring;
· length / height of the spring in the free state (without load);
· spring pitch (this is the distance between the middle of the wire diameter of one turn to the middle of the wire diameter of the next turn);
· number of turns working / full.
Compression spring quality
This product quality is obtained due to the observance of the main parameters of finished products made according to the drawings:
· wire diameters;
· parameters of reference turns;
· sections of turns;
· wire sections.
Compression springs are also manufactured using high quality metal heat treatment technologies.
Also no less important is the choice of material (spring steels) that meets the requirements of GOST for the required characteristics of the product, taking into account the scope of the springs.
Scope of compression springs
The compression spring is used in all industrial areas related to the technical field.
Elastic deformation, as the main property of helical compression springs, allows them to be used for work with loads applied along their winding direction due to their cylindrical shape.
Therefore, they definitely perform the function of shock absorption, vibration isolation and buffer.
Used steel grades
Compression springs are designed to shorten under load. The coils of such springs do not touch each other without load. The end turns are pressed against the neighboring ones and the ends of the spring are ground.
The materials for the manufacture of compression spring wire are high-carbon, alloyed, stainless steels, copper alloys from 0.2 mm to 30 mm.
· 60С2А GOST 14959-79
· 51HFA GOST 14963-78
· 50HFA GOST 14959-79
· EN-10270-1 analogue of steel according to GOST 9389-75
· EN-10270-2 analogue of steel according to GOST 14963-78 -60С2А
· EN-10270-3 analogue of steel 12X18H10T
· 40X13
· steel 70 B-2 / B-1 / A-1 GOST 9389-79
· stainless steel 12X18H10T according to TU 3-1002-77
· bronze BrKMts, BrB2
Used types of coatings
Compression springs, which you can buy in our company, have several coating options.
Galvanized galvanizing
Metal galvanizing is a technological process, the essence of which is to apply a special zinc-containing composition to the surface of metal parts.
This procedure is designed to prevent the formation of oxides and rust, which favorably affects the service life of metal structures of any type.
Galvanizing provides the product with reliable protection against rust.
The treatment of compression springs with zinc is used more for decorative purposes. The coating is applied evenly without sagging, so the products are of high quality.
Ways and methods of galvanizing
· hot dip galvanizing
· Cold galvanizing
· Galvanic method
· Thermal diffusion coating with zinc
· Zinc thermal spraying
Primer - enamel 3 in 1
Enamel serves as a reliable protection against rust.
These types of paints belong to the category 3 in 1.
They contain 3 components:
· primer;
· anti-corrosion enamel;
· metal paint.
In addition, the compression spring treated with this composition is resistant to temperature extremes and chemical compounds.
Other benefits of coverage:
· elasticity;
· water resistance;
· attraction.
Polymer powder coating
It has excellent surface adhesion and corrosion resistance.
Does not respond to temperature changes, chemical and mechanical impacts, provides electrical insulation
Powder coating is characterized by a high degree of protection and presentation.
Advantages:
· proven adhesive properties;
· rust resistance;
· guarantees electrical insulation to the elements;
· resistance to temperature preparations;
· resistance to chemicals.
Phosphating with oiling
Phosphating protects springs from rust (corrosion) by forming a layer of slightly soluble iron, zinc or manganese phosphate on the spring surface.
The phosphating coating has a high electrical resistance, withstands voltages up to 500 V.
Phosphating types:
· Cold (low temperature)
· Normal
· Accelerated (electrical insulating)
· electrochemical
Non-electrolytic zinc lamellar
Lamellar galvanizing provides protection that combines the properties of a galvanic couple and a paint coating.
This coating reliably protects the product during operation.
Advantages:
· elasticity;
· resistance to temperature extremes;
· immunity to the effects of chemicals;
· rust resistance.
Oiling
A layer of neutral oils is applied to the surface of the springs, which increases the protection of treated metal surfaces, both during storage and during operation.
This is a temporary protection against rust. This processing of springs is carried out for the period of transportation of the elements, as well as a technological coating for the use of springs in production.
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