Urethane Casting

Urethane Casting, also known as Polyurethane Casting or Vacuum Casting, uses silicone molds to manufacture plastic and rubber parts among Vacuum process.  

Urethane Casting is a mold process that meets the needs of customers for small batches of parts. It is similar to a simple mold and can be easily copied 10 to 22 times. Although it has strict requirements on the wall thickness and structure of the replication target, this does not prevent it from becoming a processing technology that engineers love. As one of the rapid prototyping processes, it is more Cost-Effective and has a more flexible delivery time compared to CNC machining.

How Does Urethane Casting Work?

1). Prepare the 3D file of objects.

Based on 3D file from customer, we have to analyze if its suitable for Vacuum casting by our skillful Engineering team.

2). Make a master model

It is best way to prepare the master unit by CNC machining or 3D printing before the Silicone molding is made.

3). Make silicone rubber mold

Prepare a casting box with built-in cores, inserts and other components, and then place the master mold in the casting box and fix it. Next, inject silica gel into the casting box so that it fills every corner and every detail in the box. Then put the whole device in a 40°C oven and cure for 9 to 16 hours. After the silicone rubber is cured and dried, the box and the riser are removed, the parts and the mold are separated, and the negative cavity is exposed, and the mold is completed.

4). Pouring polyurethane resin in mixing ratio

Before mixing the polyurethane resin, the two-component polyurethane resin is preheated to about 40°C, and then mixed according to the hardness of the parts. In the next step, the two-component polyurethane resin mixed in proportions is injected into the mold through the machine. During this process, vacuum conditions are required to avoid the problem of air bubbles in the casting.

5). Remove the casting

After pouring, the mold is placed in the oven for curing. After curing, take it out and proceed to the next finishing process.

Urethane Casting Applications Low-volume production Bridge tooling Pilot runs Functional prototyping	Urethane Casting Materials Standard Silicone (30, 40, 50, 60, and 70 durometers) Medical-Grade Silicone Optical-Grade Silicone Fluoro silicone (fuel and oil resistant)

Urethane Casting Capabilities

Max Part Size                             300mm*200mm*100mm

Tolerance                                    +/-0.05mm