Calculators for Injection Molding Technologists

Calculate the weight of an injection molded part based on volume and material density, including the runner system.

Determine the mold cavity dimension accounting for processing shrinkage of the polymer material.

Calculate mold cavity dimensions with shrinkage compensation in flow and transverse directions.

Calculate the required shot size, barrel capacity, and screw diameter for your part.

Determine the optimal runner diameter based on part weight and runner length.

Calculate the maximum flow path length and flow-path-to-wall-thickness ratio (L/T).

Estimate the mold filling pressure based on flow path, wall thickness, and melt viscosity.

Calculate the required clamping force based on projected area, pressure, and number of cavities.

Determine the ejection force based on lateral surface area, draft angle, and surface roughness.

Calculate lateral forces acting on side cores under injection pressure.

Determine the compression force based on area, pressure, and material thickness.

Calculate optimal part cooling time using the Ballman-Shussman method based on thermal parameters.

Determine the actual melt temperature accounting for shear heating and back pressure.

Calculate the heat balance — sensible heat, latent crystallization heat, and total energy to be removed.

Calculate required cooling power and water flow rate based on shot weight and cycle time.

Calculate the thermal expansion of the hot runner manifold and the required compensation gap.

Determine dimensional changes due to temperature variation based on the expansion coefficient.

Determine the full injection molding cycle time — injection, holding, cooling, and mold movements.

Calculate OEE, production efficiency, and actual parts per shift.

Break down part production costs — material, machine, labor, overhead, and profit margin.

Calculate mold cost per part, break-even point, and total tooling cost including maintenance.

Calculate ROI, NPV, payback period, and IRR for your injection molding project.

Determine part tolerance limits and cavity dimensions based on tolerance class.

Calculate the Reynolds number and determine flow characteristics in the runner channel.

Determine the optimal number of cavities based on production volume and costs.

Calculate mold plate deflection under cavity pressure and verify the safety factor.