All Categories


Home > BLOG > Which is better for plastic isolation piers, blow molding or roto molding?

Which is better for plastic isolation piers, blow molding or roto molding?

July 07,2022

Whether the plastic isolation pier is a good blow molding process or a good rotomolding process has always been a matter of constant debate in the plastic products industry.

Isolation piers are also called water horses. Commonly used are cement isolation piers, glass fiber reinforced plastic isolation piers and plastic isolation piers. Water horses are mainly used for transportation facilities and play a protective role. Today’s discussion is mainly about plastic isolation piers.

The isolation pier of the blow molding process can make the wall thickness of the isolation pier more uniform and use less material. Because it is high-density polyethylene, it has better stretch ability, so it can be recycled more frequently.

The rotomolded is low-density polyethylene. Due to the material properties, it will be easily broken after being hit by a collision. However, the machine cost of the rotomolded isolation pier is lower, and the shape can be diversified. For example, a crown-like shape can be added to the top to make the isolation pier look more beautiful and eye-catching.

Next, for the question of whether the plastic isolation pier is a good blow molding process or a rotomolding process, we will make a detailed comparison from four aspects: process, cost, product appearance, and mold.

Process comparison:

The rotational molding process is to first add plastic raw materials into the mold, and then the mold is continuously rotated along two vertical axes and heated. The entire surface of the cavity is formed into the desired shape, and then cooled to form a product.
In the blow molding process, a tubular parison is first extruded, a section of the tubular preform is cut and placed in the mold, the split mold is closed, and the upper and lower ends of the embryo are clamped at the same time. Cool to shape.

Cost comparison:

The cost of rotomolding molds is high;
The cost of blow molding is low, and for products of the same size, the cost of blow molding is about 1/4 of the cost of rotational molding.

Appearance comparison:

The edge strength of rotomolding products is good, and the thickness of the edge of the product can be more than 5 mm, which completely solves the problem of the thin edge of the product; the rotomolding can also place various inserts; the shape of the rotomolding product can be very complex, and Thickness over 5 mm; rotomolding can produce fully enclosed products.
Blow molding products can be designed with multiple layers and filled with foam materials to achieve thermal insulation.

Mold comparison:

There is no need to adjust the mold for rotomolding, and the wall thickness of the rotomolded product can be adjusted freely. The product is hollow and seamless, but the wall thickness can be adjusted to give the product high strength. It can also provide a variety of surface pattern treatments, produce various color products, can be used for anti-ultraviolet and anti-aging treatment, and can be used for a variety of stone and wood simulation effects.
The blow mold has a simple structure, low investment and easy operation, and is suitable for hollow blow molding of various plastics; the disadvantage is that the wall thickness of the parison is uneven and the production efficiency is low.

Bekwell is a large-scale hollow blow molding machine

manufacturer that does a good job of plastic isolation piers in the blow molding process. It also has an independent production workshop. Both equipment and molds can be produced independently, which can realize the fit of equipment and molds.

After the comparison of the above aspects, it can be found that whether the plastic isolation pier is a good blow molding process or a good rotomolding process, this is inconclusive, and it should be treated objectively. Here is just a brief discussion of two different processes. Everyone still has to choose according to their actual situation.