How do you design a rib for plastic products?

When designing a rib for a plastic product, there are several key factors to consider to create a strong, durable, and effective design. 

By following a set of plastic injection molding design principles and guidelines, manufacturers can create ribs that are effective at enhancing the strength and performance of their plastic products.

What is a rib for plastic products?

A rib height is a protrusion that extends from the surface of injection-molded plastic parts and is typically used to provide additional strength and rigidity to a specific area of the injection molded parts.

What is the function of ribs?

Ribs are used in plastic design to provide additional support and reinforcement to the body of a part, allowing it to withstand higher stresses and loads without failing or deforming. 

What are the types of ribs?

1. Ribs of two distinct types are present in architecture. The first type, shown in Picture 1 is a long grid rib pattern while the second depicted by Picture 2 displays circular ribs, creating an entirely different look and feel.

2. To ensure structural integrity, reinforcing ribs are strategically placed on the corners and side walls of the cabinet – a detail visible in Pictures 3 and 4.

3. The column is designed with stiffeners, as Picture 5 shown.

What is a rib design principle?

1. The thickness

The uniform wall thickness of the reinforcing rib thickness should be smaller than the nominal wall thickness of the reinforced product to prevent depressions at the joints.

The ribs’ size is carefully calibrated – at 0.4 to 0.5 times the thickness of the plastic material, typically settling at around half for optimal strength and durability.

2. The height

Figure 3 illustrates the correlation between rib dimensions and product rigidity. To ensure maximum strength, an increased number of ribs should be implemented rather than raising their height as too much force may cause irreparable damage.

3. The slope

The slope of the rib can be larger, generally greater than 1.5°, to avoid top damage and facilitate demolding.

4. The location arrangement

Efficient rib design is essential to creating strong, high-performing plastic products.

To ensure success in injection molding projects, manufacturers must arrange staggered reinforcing ribs with precision – this ensures that the product will be more resistant to uneven shrinkage caused by manufacturing processes and use conditions.

With an understanding of key engineering guidelines, designers can produce superior results for any industry or application!