Compression springs are the most popular and most commonly used type of springs. They are used in all aspects of our lives. They are characterized by a space between the coils called the pitch of spring. Compression springs have active coils, which transfer the stresses acting along the axis of the spring and the passive coils - usually located at the ends of the spring. Their function is to create two planes parallel to each other and perpendicular to the axis of the spring. These planes facilitate operation with other elements of the spring.
Thanks to the passive coils, the operating direction of the compression spring load force is much closer to the axis of the spring. In many cases the end coils of the springs are ground to enhance this effect and increase their life span and efficiency. EN Standard 15800:2009 concerning compression springs determines the grinding method and deviations that may arise during the process.
Compression spring. With closed coil and ground ends - type 1; with closed ends - type 2; or without ends - open coils, not ground.
Definitions of symbols used:
|ø d||mm||wire diameter|
|D||mm||spring pitch diameter|
|Di||mm||inner diameter of the spring - the most frequently given and tolerated in a case where the spring operates on a pilot bar|
|De||mm||outer diameter of the spring - the most frequently given and tolerated in a case where the spring operates in a pilot hole (slot)|
|Dd||mm||diameter of the pilot bar (piloting inside the spring)|
|Dh||mm||diameter of the pilot hole (piloting outside the spring)|
|F||N||spring force - given in tandem with the height of the spring in a load state or with a deflection of the spring sa|
|L0||mm||Nominal height of the spring in a free state.|
|L1, L2, …||mm||The length of the spring loaded with force F1, F2, …|
|e1||mm||permissible deviation from perpendicularity of an unloaded spring|
|e2||mm||permissible deviation from parallelism of the springs ground surface to the unloaded outer diameter|
If the compression springs work in a hole with a diameter Dh, we give the outer diameter of the spring (De), anticipating sufficient clearance to allow the spring to work freely. It must be remembered that during load the spring diameter slightly increases. øD
For a spring operating on a pin, more importantly will be to provide an inner diameter (Di), but not less than the pin (Dd), on which it operates. In this case, you must also assume a technology clearance that allows the spring to bend freely. This clearance should not be too large, so that the spring doesn’t buckle during operation.
If the spring operates on a bolt and at the same time fits into the hole, it is better to provide the pitch diameter (Dp).
The manufacturer of ALMECH springs offers compression springs made of high carbon spring wire with or without anti-corrosive coat and stainless steel wires. The diameter of the wires for the compression springs we produce ranges from ø 0,10 mm - ø 7,00 mm.
On customers’ request, we provide for each batch of springs produced, a test certificate on the geometrical and physical parameters.