The Kalzip E clip is a highly versatile component that allows the secure installation of Kalzip roof system accessories and various panels without penetrating the weatherproof layer of the roof or wall. The previously pure metal component is now overmoulded with a thermoplastic outer layer, thus improving the properties of the product and reducing its production cost.

Inzert ráfröccsöntés technológiával jobb és olcsóbb a tetőszerkezeti kötőelem

In this article we describe, how

We can combine the advantages of two materials with overmoulding

Product designers often aim to use the advantages of several materials at the same time to achieve superior product quality. In most cases, this is the only way to ensure that both high quality and good properties are inherent in the product at a reasonable price. For example, in the case of threaded joints, the use of metal nuts and bolts is most advantageous, but if they only appear as inserts in the product, the other parts can be made from thermoplastics or elastomers, which are lighter, more cost-effective and easier to mould.

Seam roof clips can be manufactured using 3D printing or insert moulding, however using a metal frame with overmoulding gives the product a stronger bond while retaining the beneficial properties of plastic, and remaining more cost-effective than a purely metal product of the same strengh.

In case of overmoulding, the carrier material can either be metal, plastic or glass. Some products can even be produced using a special machine that automatically assembles the substrate and the injection moulding material. The latter is most commonly an elastomer or thermoplastic, that improves the properties of the substrate, thereby providing

  • a better grip,
  • more effective insulation, and
  • an aesthetically pleasing appearance.
Aluzinc coated steel plate

Aluzinc coated steel plate

The production of Kalzip E clips with overmoulding

The Kalzip E clip is a seam roof clip moulded from polyamide on an aluminium-zinc coated steel plate. This plastic layer provides a thermal insulation effect, preventing the formation of thermal bridges.

At our Budapest production site, Mikropakk SILVER, we have been overmoulding 10 types of Klazip E clips for 10 years in 10 different sizes and finishes, with a total of 1.2 million pieces produced each year.

Manufacturing and assembly of the metal part

The raw material, sheet metal, arrives in coils at our supplier, where the parts are prefabricated to shape and size. The manufacturing of the product at Mikropakk starts with the use of the prefabricated parts, that are

  • riveted,
  • bent and
  • pressed

on our automated production line. The automatic assembly machine is capable of producing all 10 types of clips. After assembly, the plate frame is checked for faults and the inspected products are placed in boxes.

Optical inspection on a robotised production line

Optical inspection on a robotised production line

Fully-robotised ovemoulding

Operators place the finished metal frames on a conveyor rail, which transports the product to the robots. Optical inspection was formerly performed by an operator but is now carried out on our robotic production line, which checks for the presence of the head plate and any deformations. The robot then places the metal frame in the injection mould and, after overmoulding, drops it onto the ejection slide. The process ends with a check carried out by an operator, to ensure that only perfect quality products are delivered.

How we manufacture Kalzip clip products

Customised injection moulding solutions and production automation at Mikropakk

We offer injection moulding services at competitive unit costs for products with high technical specifications and new launches in low-volume, as well as high volume production runs.

We work with the latest technology. Our equipment is suitable for 1, 2 and 3 component injection moulding, insert moulding, injection blow moulding and cubic technology. We prefer a solution-oriented approach, which can include expanding our machine fleet if the production of a new product requires. Contact us for more information!

Related capabilities