Select Page

The caps and ferrules we produce at FORTAPS serve as plugs to prevent metal tubes from corroding in metal structures exposed to weather, among other uses. In that way, they act avoiding wear affecting the service life of the structure.  At the same time, they avoid cuts, injuries or accidents that people may suffer from contact.


Plastic parts exposed to weather experience a number of effects that can affect their integrity and durability over time.

  • First, ultraviolet (UV) radiation from the sun can cause polymer degradation, resulting in color loss, cracking, and reduced structural resistance.
  • Continuous exposure to moisture can trigger corrosion processes and promote the growth of fungi, mold or algae, compromising the aesthetics and functionality of the parts.
  • Extreme temperature variations, from searing heat to intense cold, can cause mechanical stresses on the plastic, leading to brittleness and deformation.
  • In addition, the presence of air pollutants, such as gases and particles, can accelerate the process of chemical degradation.

Together, these factors highlight the importance of having weather-resistant plastic materials, able to maintain their performance and appearance despite climatic adversities.

In the specific case of caps and ferrules, their main function is to protect the metal structures from corrosion by preventing the entry of water into the tubes. It also protects people from the cutting edges of the tube to avoid damage.

Our customers frequently inquire about the durability of outdoor caps, as manufacturers of fences, enclosures, road signs, sports facilities, and street furniture frequently encounter these problems:

  • Caps that come out of the tube, leaving it exposed and affecting the safety and durability of the structure.
  • The degradation of colors has an impact on aesthetics.
  • The caps’ deformity is affecting both aesthetics and safety.

Plastic parts that are placed outdoors will be exposed to various climatic conditions, which can vary from harsh winters to scorching summers. These pieces must continue to perform the function for which they were conceived and designed effectively under all these circumstances.

Therefore, it is vital to ensure maximum durability of the caps to avoid degradation of metal structures or accidents with the cutting edges of the tubes.

In this context, Low Density Polyethylene (LDPE) stands out for its inherent versatility and resistance, being an optimal option for injecting parts intended to be installed outdoors.

Our decision to use this material in FORTAPS is based on this reason.

  1. We use exclusively virgin material (not recycled)
  2. The material is translucent, Dyeing is made “in mass” adding high quality dyes.
  3. Adding carbon black is an economical and generally very effective way to get UV resistant plastics

By adding elastomers to the composition of this polymer, it can dramatically improve its weather resistance capabilities, which are known for their low density and flexibility.

We describe the measures taken in FORTAPS to enhance durability, the characteristics of LDPE, and analyze how the addition of elastomers enhances their characteristics, particularly with regard to resistance to adverse weather conditions.

LDPE, Low-density polyethylene

Low density polyethylene (LDPE) is a type of plastic characterized by its flexibility and ability to resist chemicals

The advantages of low density polyethylene (LDPE) are closely related to its properties per se and can be summarized in the following points:

  1. Flexibility and durability: LDPE can be significantly molded without breaking.
  2. Impermeability: Its moisture resistance prevents liquids from leaking.
  3. High impact resistance: Although it has low tensile strength, its impact resistance makes it durable.
  4. Chemical resistance: High resistance to chemicals
  5. Extreme temperature resistance: It can maintain its shape in a temperature range of -40C to 90C, making it suitable for applications in extreme conditions.
  6. Electrical insulation: Its property as a bad conductor of electricity makes it useful for insulation in electrical wires and cables.
  7. Cost-effective and recyclable: It is economical to produce and widely recyclable, making it attractive for mass manufacturing and reducing environmental concerns.

The use of elastomers can increase weather resistance.

Our choice for improving LDPE polyethylene’s properties is to add elastomers to the virgin material’s composition. This modification process significantly improves LDPE’s resistance to adverse weather conditions, such as UV radiation, humidity and temperature fluctuations.

Advantages of Elastomer Addition

  • Improved UV resistance: Prolonged exposure to ultraviolet radiation can degrade plastic materials, but the addition of elastomers strengthens the resistance of LDPE, extending its life in outdoor environments.
  • Low Temperature Flexibility: Elastomers improve the ability of LDPE to maintain its flexibility even under low temperature conditions, which is essential for cold weather applications.
  • Durability and Impact Resistance: The combination of LDPE with elastomers improves the overall durability of the material and its ability to withstand impacts, contributing to more robust and reliable end products.

Practical Applications

This improvement in weather resistance makes the modified LDPE ideal for weatherproof metal structures, ensuring that the tops maintain their properties and carry out their farming throughout the life of the structure.


The success of plastic injection manufacturing requires understanding the properties of materials. Low Density Polyethylene (LDPE), in combination with elastomers, proves to be an exceptional choice by offering not only versatility and strength, but also greater durability in challenging environments.

In order to respond to the needs and concerns of our customers (especially those located in the northern part of Europe), at FORTAPS we inject our entire range in virgin PELD polyethylene, to which an elastomer is added to achieve the best possible result.

Realiable ferrule supplier