SPRING MANUFACTURER

When a conventional spring, without stiffness variability features, is compressed or stretched from its resting position, it exert an opposing force approximately proportional to its change in length this approximation breaks down for larger deflection. The rate or spring constant of a spring is the change in the force it exerts, divided by change in deflection of the spring. The is, it is the gradient of the force versus deflection curve. An extension or compression spring's rate is expressed in unit of force divided by distance, for example or N/m or Ibf/in. A torsion spring is a spring that works by twisting; when it is twisted about its axis by an angle. A torsion spring's rate is in unit of torque divided by angle, such as N.m/rad or ft.lbf/ degree. The inverse of spring rate is compliance, that is : if a spring has a rate of 10 N/mm,ithas a compliance of 0.1 mm/N. The stiffness or rate of spring in parallel is additive, as is the compliance of spring in series.

Spring are made from a variety of elastic materials, the most common being spring steel. Small spring can be wound from pre-hardened stock, while large ones are made from annealed steel and hardened after manufacture. Some nonferrous metal are also used, including phosphor bronze and titanium for parts requiring corrosion resistance, and low - resistance beryllium copper for spring carrying electric current.