FAQ

It depends on how the injection mold was designed in some cases. Injection molds are constructed by inserting steel into a mold base and assembling them together to make the feature of the part. Modifying or rebuilding a small steel insert is all that is required to change one feature of the part. Some design changes can be more challenging when the entire part design is cut out of one piece of steel, requiring reworking the mold.

This depends on the size and geometry of the parts. For a common open and shut mold with regular size part such as 300 x 300 x 50 mm, fabrication of tools and moldings can be done within 2 weeks.

That being said, many factors go into determining the full cost. The start-up costs for a large run can be expensive, but the price for the project becomes better and better as you continue to produce. If you’re looking at price per unit, plastic injection molding is one of the cheapest, most cost-efficient forms of manufacturing. With injection molding, the more units you create with your mold, the cheaper the price per unit becomes.

With injection molding, we can mold fairly complex shapes at high production rates while maintaining good dimensional stability and holding fairly tight tolerances. It is possible to reground and reprocess thermoplastic resin used in injection molding, but some of the plastic’s physical properties may be lost over each round of regrinding. When manufacturing large volumes, using engineered plastic resins instead of metal can result in many cost savings.

Once the plastic material leaves the heating tube, the front-end plastic that first touches the mold will start to solidify and adhere to the mold. At this time, the rear-end plastic will continue to flow forward over the solidified plastic, and then contact the next section of the mold and adhere. After repeated occurrences, fine lines like water waves will be formed; water ripples are also one of the defects that we often mention when learning plastic injection knowledge, and are related to the mold temperature, raw material temperature, and injection speed of the injection machine. Very closely related, water ripple defects are a problem encountered by many plastic injection plants.

• Solution 1: Strengthen the fluidity of the raw material, such as increasing the temperature of the raw material, or directly replacing the raw material with better fluidity, so that the plastic material can be uniformly solidified in a short time.
• Solution 2: Increase the temperature of the mold, reduce the temperature difference between the plastic material and the mold, and reduce the solidification speed of the raw material.
• Solution 3: Increase the injection speed and pressure, so that the plastic material can quickly fill the entire mold, and there will not be too much difference in the solidification time.

Depending on the type of plastic raw materials, the characteristics will have some differences. If the hygroscopicity of the material is relatively high and it is easy to retain moisture, or the plastic is easy to mix with air, then after the water and gas enter the mold, it is easy to attach to the mold. On the surface, silvery white lines are formed after injection, which is what we often hear about silver lines and gas sores; in order to reduce the generation of silver lines, operators must have a certain understanding of plastic injection knowledge.

• Solution 1: Adjust the temperature and time of drying raw materials according to the properties of different raw materials, especially for materials with high requirements such as PMMA. As long as the materials are free of moisture and then injected, the chance of silver lines on the surface of the product can be reduced.
• Solution 2: If there are different types of materials to be mixed, it is recommended to stir the plastic raw materials evenly first.

In general, we can predefine the material types for each component comprising a knee joint prosthesis:

• Knee Joint Surface: Titanium (a mixture of 30% chromium, 7% molybdenum, along with cobalt, nickel, and other materials).
• Femoral Component of the Knee Joint Prosthesis: Typically utilizes two materials - cobalt-based alloys or a titanium alloy known as Ti6Al4V.
• Tibial Component of the Knee Joint Prosthesis: Primarily composed of cobalt-chromium alloys, with titanium alloys discussed above as a secondary option.
• Insert: Polyethylene serves as a mixture for high-strength plastic components, providing flexibility for bending, extension, and rotation of the femoral component on the tibial component.

Regardless of how materials are categorized and the generalities discussed above, it should be noted and remembered that there are numerous types of titanium knee joint prostheses and other components available on the market.

Each project is unique, so we require varying amounts of time to build molds. 8-10 weeks on average, depending on the complexity and cavitations of the mold.

Yes, but only to evaluate the prototype part prior to producing production tooling. We do not build prototype tools as a service. We are a high volume molder and the amount of production parts from a prototype tool is limited.

Plastic injection molding offers unparalleled versatility, and plastic parts find applications in nearly every industry. The most common uses of plastic injection molding are typically found in the packaging, consumer goods, electronics, automotive and transportation, construction, and medical equipment industries.

Titanium possesses exceptionally high strength and an impressive strength-to-weight ratio. In fact, its strength is only 5% less than that of steel, yet it is 40% lighter. This makes it extremely well-suited for high-tech industries such as aerospace, automotive, and energy.

Titanium is more challenging to machine than steel, primarily due to its high melting point. Its high ductility, often leading to elongation before fracture, also makes machining more difficult.

1. Part drawings: 2D: pdf; 3D: x_t, step, for complex parts, both 2D and 3D drawing are necessary.
2. Material specification, e.g. Aluminum 6061, Steel 1020, Stainless steel 304.
3. Coating/Surface treatment, e.g. As machined, brushed, anodized, plated, powder coated, bead blasted, sand blasted.
4. Quantity for each order, Annual volume or even annual volume of the next coming years.
5. General tolerance standard