The problem

A pipe fitting for drinking water systems, designed to be installed — often underground — by someone working on site, not in a lab.

The original design used four separate components, sold individually:

• a brass pipe connector
• a nylon ring
• a conical rubber seal
• a threaded cap

Once assembled, the cap compressed the nylon ring against the pipe, locking it in place. But the multi-step assembly, left to the installer, created a recurring problem: the nylon ring or the conical rubber seal could be left out during assembly.

On a visible fitting, that kind of mistake is caught immediately. On a fitting that ends up buried with the pipe, it only surfaces once water starts leaking — often too late, and far more expensive to locate and fix.

The solution

We proposed rethinking the product itself, not just the material.

The first step was eliminating two separate components — the nylon ring and the conical rubber seal — and replacing them with a single part: a glass-fiber-reinforced PA6.6 insert, overmolded directly with a rubber compound certified to KTW standards for contact with drinking water. No more loose parts that need to be positioned correctly one by one: the subassembly arrives exactly as it should be, with no risk of separation or misalignment.

The second step is the one we worked on the longest, and it’s also the part we’d rather walk you through in person than spell out in writing: a design solution that smartly separates two functions — mechanically retaining the pipe and sealing against leaks — so that fluid pressure, instead of being a risk to the seal, becomes a factor that reinforces it.

The third step was our own initiative: we proposed pre-assembling the entire fitting at the factory, with the new subassembly already fitted inside the connector body (the brass components remained supplied and assembled by the customer). The result for the installer: nothing to assemble, nothing to forget. Just insert the pipe and tighten.

The result

• From 4 separate components to a single overmolded subassembly that cannot be partially assembled
• A seal that performs better under pressure, not worse — the opposite of what happens with many traditional solutions
• A single supplier for the critical component, instead of two materials to manage separately
• No chance for the installer to leave a part out

The strongest validation? The solution we developed later turned out to be original enough to be patented — an indirect but concrete acknowledgment of the work behind it.

HTP designs and manufactures overmolded rubber-to-metal and rubber-to-plastic components for technical applications where mistakes aren’t an option. Got a sealing or assembly problem keeping you up at night? Let’s talk.

Foresti Alexander

L'articolo When a missed step is not an option proviene da HTP - High Tech Project.

When they called us, the project was nearly dead.

Three years of attempts, different suppliers, resources invested. And the problem was still there, unsolved. They were seriously considering giving up on the entire project.

We sat down with their technical team and listened. Not just to the stated problem — but to everything: the actual operating conditions, the system constraints, what they had already tried and why it had not worked.

The problem

The component was a machined die-cast aluminium valve with very tight tolerances and a stainless steel pin integrated into the upper section. The requirement was to overmould two sealing gaskets simultaneously — one at each end of the valve, 180 degrees apart.

But that was not all. During the discussion, a critical requirement emerged that further complicated matters: the compound had to ensure low friction under operating conditions. The part operates in a system where actuation force must be minimal — yet the seal must be reliable and consistent over time.

Two requirements pulling in opposite directions. And which explains, at least in part, why others had failed.

Why aluminium is a challenging substrate

In our line of  work, we know this all too well: aluminium is one of the most complex substrates to work with. It is not like steel. Its surface oxidises naturally, with chemical properties that vary depending on the alloy, the surface treatment, and even the storage conditions of the component.

Achieving a durable structural bond between rubber and aluminium requires: specific and controlled surface preparation, primers and bonding agents compatible with that specificalloy and the selected compound, process parameters optimised to the last detail; and a mould designed to manage the flow of the compound on both sides simultaneously.

There are no shortcuts. Every variable matters.

Three years of failed attempts

The customer — a multinational industrial group — had already faced the problem head on. For almost three years, various suppliers had attempted to develop a solution. These were large companies, with in-house resources and laboratories. The result was always the same: an inability to guarantee stable, long-lasting adhesion, or sealing issues under real operating conditions.

The project was on the verge of being abandoned.

What we did

We worked on three fronts simultaneously: selecting and optimising the compound to meet the required tribological characteristics, developing a surface treatment process specifically tailored to that aluminium alloy, and designing the mould for the simultaneous overmoulding of the two gaskets at 180 degrees, with the stainless steel pin as the central element to be managed.

It was not straightforward. But it is exactly the sort of problem we are used to dealing with.

The result

Four weeks after our first meeting, we delivered the samples in the smallest size.

I will never forget the technical team’s reaction. After three years of failed attempts, they did not expect to see those samples so soon. And above all, they did not expect them to work.

They worked.

We currently manufacture four sizes of that component using 4-cavity and 8-cavity moulds. We have been in production for over four years, maintaining consistent quality and with no issues encountered in the field.

If you are facing a similar problem

Overmoulding on aluminium is not impossible. It is complex, requires specific expertise in materials, surface treatments and process, and leaves no room for approximation.

If you have a sealing challenge that others have not been able to solve — on aluminium, special alloys, engineering plastics, or stainless steel — get in touch. The first thing we do is listen.

Foresti Alexander

L'articolo Double-seal overmoulding on aluminium: when the solution seemed impossible proviene da HTP - High Tech Project.

Customers are often not specialists in sealing, and therefore prefer to use outdated or less efficient systems in order to avoid taking risks.

However, the current market requires companies to present new products and technical developments that enable them to resolve issues by addressing not only technical aspects but also economic ones.

The choice of materials is of great importance for a sealing gasket, and especially so if it is overmoulded.

The importance of selecting materials that are compatible with all working conditions, and not just those of the seal, cannot be underestimated.
Very often, compromises must be made, precisely because no compound or insert is resistant to ‘everything’.

It is precisely in these cases that it is essential to have a truly competent partner at your side.
And competence is not demonstrated on paper, or because you are a well-known name on the market, or because you have the ‘best’ price.

This is demonstrated by decades of presence in that specific technical field, in the development of complex projects, in the production of technically difficult items with multifactorial implications, where even the most ordinary piece of information can become a fundamental point to consider.

Furthermore, all of this must then be included in an overall economic assessment, which is often not taken into consideration in its entirety, allowing the customer to approach their new project with complete confidence in their new partner.

All this is the beating heart of High Tech Project: absolute, all-round Expertise.

Your future strategic partner!!!

Foresti Alexander

L'articolo Choosing your strategic partner proviene da HTP - High Tech Project.

The question I have to ask myself every day, not only at home, in the car, in the workplace is: ‘What am I doing?’, a very important reflection we have to make in order to avoid unpleasant and sometimes painful consequences.

This is why the topic of SAFETY in companies is crucial and here are some reasons:

1. Protecting employees
   Safety at work is essential to ensure the health and well-being of workers. Proper training helps prevent injuries and illnesses.
2. Legal compliance
   Companies are often required to comply with specific safety regulations. By training, they ensure that their workers are aware of the laws and rules to be followed, reducing the risk of legal sanctions.
3. Culture of safety at work
   Training helps to create a safety culture within the organisation. When workers are aware of risks and safety protocols, they are more likely to behave responsibly.
4. Reducing costs
   Investing in training can lead to a reduction in costs associated with work-related injuries such as medical expenses, compensation and loss of productivity
5. Emergency Response
   The training prepares workers to handle emergency situations, such as fires or chemical accidents, enabling a prompt and coordinated response.
6. Improving productivity
   A safe working environment promotes productivity, as workers can better focus on their tasks without distractions or concerns about their safety.
7. Corporate reputation
   Companies that spend on security training generally tend to build a positive reputation by attracting talent and customers sensitive to these issues.

In conclusion, safety training not only protects workers, but is also a strategic investment in the long-term health and sustainability of the company.

This is why High Tech Project is always careful on this matter, and in October and November safety courses were carried out internally for all workers. The decision to hold in-house courses is closely linked to the fact that we want to contextualise as much as possible the risks in our own workplaces and make the staff reflect on their own reality, bringing examples of everyday working life, in the hope that what they learn in the courses can also be useful outside the workplace.

Valentina Foresti

L'articolo The importance of security in companies proviene da HTP - High Tech Project.

4. Cost-effectiveness: although the initial investment may be higher than other forms of seals, their long life and low maintenance requirements can lead to significant savings in the long term.

5. Materials: overmoulded gaskets can be made from different types of rubber, allowing the strength and flexibility properties to be optimised for the specific application. In addition, through design, the use of the substrate onto which the rubber seal is overmoulded is also maximised.

In brief, the use of overmoulded rubber seals is often a strategic choice to improve the functionality and reliability of the products in which they are used.

Foresti Alexander

L'articolo Why is it worth considering applying an overmoulded rubber gasket to your sealing systems? proviene da HTP - High Tech Project.

L'articolo HTP at the International Suppliers Fair (IZB) 2024 proviene da HTP - High Tech Project.