Meaning
Conical disc washers arranged in a series or parallel configuration provide high spring force within a limited physical space. A belleville spring stack is frequently used in hot runner systems to maintain a constant load on sealing components. These assemblies compensate for the thermal expansion of the manifold by compressing under the applied load.
They ensure that the interface between the nozzle and the manifold remains sealed against injection pressure.
Load Distribution
Arranging the discs in a specific orientation determines the total force and the amount of travel available to the system. A belleville spring stack can be tuned to provide high pressure with minimal deflection.
Thermal Compensation
Maintaining a seal during the transition from cold to hot states is the primary function of the assembly. As the steel expands, the belleville spring stack absorbs the movement while keeping the sealing force within a safe range. This prevents the crushing of components while stopping the leakage of molten polymer.
Fatigue Resistance
Choosing high-quality spring steel ensures that the stack retains its tension over millions of cycles. Because the moulding environment is hot, the belleville spring stack must resist tempering or loss of elasticity. Regular inspection confirms that the discs have not flattened or cracked under the constant stress of production.
Sudden loss of pressure often indicates that the stack has reached the end of its functional life. High-temperature alloys extend the duration between required service intervals for these spring sets.
