Class 8 Clean Room Moulding

ISO Class 8 clean rooms, our facilities support us to provide high quality, end to end commercial manufacturing solutions in China.

Class 8 Clean Room

Joey ISO Class 8 clean room, built to manufacture high-quality products, including baby products, houseware, assembly and packaging.

The state-of- the-art clean room facility maintains an environment that complies with ISO 13485, maintaining low levels of environmental contaminants such as pyrogens, dust, microbes, aerosol particles and chemical vapours.

LSR
Liquid silicone rubber is supplied in two-component form, in 2 x 20 kg containers or in 2 x 200 kg drums. The dosing unit pumps components A and B directly from the containers or drums in a 1: 1 ratio into the mixer and further into the injection cylinder of the injection molding machine. If necessary, the dye is supplied to the mixer via a separate line.

There are no moving parts in the static mixer. The material is mixed to a homogeneous form by forcing it through rigid mixing elements inside the mixer. After mixing components A and B, the material can be injected into the mold.

The mixed material is metered and injected into the mold by the screw in the injection cylinder. Modern injection molding machines offer precise control of the injection process.

Injection and vulcanization

LSR – There are two ways to bring the material to the seat: direct fill, cold runner and indirect fill (cold nozzle and hot sleeve). Each method has its own advantages and disadvantages.

Direct infusion

The material is injected into the cavity through a cold channel. The cold runner needle valve system has additional advantages such as less shear on injection.

Advantages:

  • The products do not require additional processing (no ingot and flashes)
  • Possible high degree of automation
  • Less material consumption (no ingot)

Defects:

  • High cost of designing and manufacturing an injection mold
  • Higher costs of a multi-cavity injection mold (requires a separate cold runner for each mold)

Indirect infusion

Material is injected into the seat through an injection sleeve and gating channels. The vulcanized ingot must be removed into the mold with the product.

Advantages:

  • Cheaper mold making
  • Suitable for low and medium batch sizes

Defects:

  • Higher material consumption (ingot waste)
  • Additional processing required (removal of the ingot and flashes)
  • Unsuitable for fast-crosslinking systems (risk of scorching in runners)

Cross-linking temperatures and times depend on the quality of the heating system and the material, size and shape of the manufactured detail. Most often, liquid silicone is processed at a temperature between 150 ° C and 200 ° C.

Injection molding is especially recommended for high volume production of small to medium sized components such as:

Teats for baby bottles
Medical components
Sealing rings
Suction cups for the automation of production processes

Material selection

Both solid silicone and liquid silicone are suitable materials for injection