Fridge Door Liner & Appliance Product Design

Pars Appliance, an established domestic refrigerator and appliance manufacturer with large-scale production facilities in Iran, required an extensive redesign of their existing refrigerator-door liner. The commercial driver for the project was modernising the appliance line to include an in-door chilled water dispenser while simultaneously optimising the door cavity for improved thermal insulation.

Cadrill was engaged to execute the comprehensive mechanical redesign in SolidWorks, managing the complex internal component packaging for the dispenser tank, valves and tubing, while designing the large-format vacuum thermoforming moulds required for series production.

Refrigerator door liners are large thin-gauge plastic components manufactured using vacuum thermoforming. Adding an integrated water dispenser fundamentally disrupts the uniform draw ratio of the plastic sheet during forming, introducing significant risks of material thinning, webbing, and inadequate pocket depth.

The challenge required balancing ergonomic internal shelf storage for everyday users with the thermodynamic requirement for insulation depth and the strict draft angle, radius and venting constraints demanded by vacuum thermoforming mould tooling.

Cadrill approached the project by integrating industrial packaging, thermoforming physics and tooling design in SolidWorks:

Internal Packaging & Dispenser Integration: The water reservoir housing, dispensing valve cradle and pass-through conduits were packaged seamlessly into the door profile. Door bin retaining ledges and bottle guards were reconfigured around the dispenser without sacrificing usable storage.

Insulation Cavity Optimisation: The back profile of the liner was sculpted to increase the clearance envelope for injected polyurethane foam insulation, eliminating thermal bridges and improving the energy efficiency of the refrigeration boundary.

Thermoforming Tooling & Mould Design: Cadrill designed the complete thermoforming mould assembly in SolidWorks. Careful draft angles, generous corner blending radii and vacuum vent evacuation hole distributions were incorporated across the mould surface to guarantee uniform plastic sheet draw without localized thinning.

To allow mould makers and plant tooling engineers to machine and commission the new tooling without delay, Cadrill delivered an all-inclusive manufacturing pack:

• Parametric SolidWorks 3D models of the final thermoformed door liner part and assembly.
• Complete 3D CAD tooling models for the aluminium thermoforming vacuum mould blocks, clamping frames and plug-assist geometry.
• 2D engineering drawings specifying critical CNC machining tolerances, vacuum hole drill patterns and surface finish requirements for toolmakers.
• Detailed interface drawings detailing door gasket retention channels and fastener locations.

Cadrill's completed engineering design allowed Pars Appliance to successfully modernise their refrigerator line. By developing both the aesthetic, functional door liner and its production thermoforming mould tooling in parallel, the client avoided costly prototype iterations and accelerated their time-to-market with a fully validated, energy-efficient dispenser door design.