Aerospace

Bonding of structural components and inserts, edge sealing, shimming, honeycomb filling or sealing of rivets and screws in the aerospace industry: ViscoTec dosing systems achieve high-precision dosing results in the aviation and space sector. This makes them the perfect component in your production process. We are specialists for the automated application of various adhesives, sealants and core fillers for suppliers and OEMs in the aerospace industry and guarantee maximum process reliability. Due to extremely gentle product handling even shear-sensitive and compressible fluids and pastes can be dosed perfectly.

We support you from the first dispensing trials to successful commissioning and throughout the entire life cycle of the dosing system. If required, we can recreate your processes in our in-house technical center, simulate the actual dispensing process and work with you to find the perfect solution for your application.

The video illustrates the wide range of applications for our dosing technology in aircraft manufacturing:

Application examples from Aviation & Aerospace

Honeycomb potting

Our products are used for manufacturing interior design components for civil and military aircraft construction. Sandwich structures are used in many areas of an aircraft (storage compartments, interiors, wings) to reduce weight. In order to structurally strengthen the honeycombs or insert them, they often have to be filled during the production process. Typical materials are one- and two-component epoxy resins with a very high proportion of hollow glass spheres. These require extremely gentle handling, as they would otherwise be destroyed, which in turn would result in an increase in density. Common application patterns are beads, circles, full surfaces and egde-filling.

The job is often done manually, which results in long production times and high running costs due to material waste. Lack of reproducibility is just as problematic as the health hazard often posed by these media.

The ViscoTec solution: Material is continuously fed to the dosing system by removal from a large container. With the help of a robot or axis system, suitable structures can be mapped reliably. A coordinated overall system delivers a dispensing result according to specification, in which operator interaction is reduced to a minimum.

The advantages with ViscoTec:

• Gentle handling maintains the material specifications
• Less rework thanks to reproducible production
• Shortened throughput times due to continuous dosing
• Viscosity-independent dosing
• Reliable process application through volumetric dosing

Edge sealing for structural components

Wing shells, side shells and fuselage sections are usually made of carbon fibre composites and glued together during the production process. With many components, a groove or an open edge remains after the bonding process, which must be filled or sealed.

A modified two-component epoxy resin is often mixed and then applied manually. This often entails long production times and complex quality controls. Equally high material costs due to the processing of materials from cartridges.

ViscoTec defies short pot life and materials that are difficult to handle: Thanks to a coherent overall system from material removal to material application, this process can be automated. The two components are taken separately from cartridges, hobbocks or drums and fed via hose lines to a two-component dosing system. Only at the very end of the process they are mixed in a static mixing tube and applied to the substrate (e.g. via a nozzle). The process is controlled and monitored by pressure sensors.

The advantages with ViscoTec:

• No material waste when mixing “just in time”
• Safe processes through pressure monitoring
• Tailored nozzle design for complicated geometries
• Shortened throughput times thanks to continuous dosing
• Reproducible production and therefor reduced rework

Automated Insert Potting / Insert Bonding

Inserts are used in the aerospace industry in lightweight sandwich panels and are then bonded. The panels can then be screwed or various components can be fastened.

However, the manual process has several disadvantages: Enormous expenditure of time for the manual filling of several thousand inserts, high material waste due to relaxation of the material, and high material costs through the use of cartridges.

ViscoTec can map the filling process automatically. The dispensing process is absolutely precise. A significant amount of material can thus be saved. In addition, material can be supplied from large containers, which in turn lowers purchase prices. Another important advantage: As a rule, no new specifications have to be made since no changes are made to the actual process.

Your advantages at a glance:

• Time savings
• Material savings
• Completely filled holes
• Clean thread breakage
• Repetitive filling processes

Sealing applications

Side shells, wing shells and fuselage structures are made of CFK, GFK, aluminium or organic sheets and get connected during production. Sealants are used to seal the connection surfaces

These are usually two-component polysulphides, which have to be applied in different geometries. Typical applications are: Fillet sealings, oversealings, interface sealings and seal caps.

Due to their properties, polysulfides require very low pressure and shear handling. The compressibility of the fillers contained in the medium requires a high level of expertise and a coherent overall system from material removal to application. With manual application, long production times and high material ejection have a negative influence on the complete process. Complex quality standards are required due to the risk of human error.

With the in-house developments of the vipro-DUOMIX from ViscoTec, this process can be depicted fully automatically. The individual nozzle design is also adapted to each application. The result is a controlled dosage in compliance with the specifications and at the same time the highest repeat accuracy.

The advantages with ViscoTec:

• Shortening of the throughput time through continuous dosing
• High process reliability and thus reduction of rework
• Mixing on request prevents material waste
• Cost savings through material removal from large containers
• Any dosing geometries are possible thanks to individual nozzle design

Mobile mix-on-demand system

The semi-automatic ViscoTec mix-on-demand station is already in successful use as a mobile system. For reliable mixing and dosing of two-component materials, in situ.

Two-component materials are commonly processed using premix cartridges, hardener rod cartridges or by mixing two components by hand. The disadvantages are obvious: The risk of human error, enormous material waste and high production costs offer every reason for taking the automated route.

With ViscoTec filling stations, epoxy resins, polysulfides and polyurethanes can be removed from larger containers and filled on-demand with the exact quantity required. The dosing is volumetric on a component or a filling container. A typical application is dosing in so-called inserts (thread inserts). The compact arrangement of the components on a mobile frame guarantees the operator maximum flexibility. The design as a stationary system has already been implemented several times.

Application example: Cartridge Filling Station

The predefined volumes of premixed-frozen and 2-component cartridges are usually not tailored to the needs of the customer. Due to ViscoTec cartridge filling stations the materials to be dosed can be provided according to the demand. In addition to the costly waste of material, environmentally conscious action is becoming increasingly important for consumers and it is a fundamental goal to reduce material waste in general.

The demand-driven filling system by ViscoTec impresses with the easy operation of the unit as well as the technology. After all, precise and gentle filling is a basic requirement for meeting the high demands of the aerospace industry. Without influencing the complex overall processes, ViscoTec cartridge filling stations can make a significant contribution to cost reduction through more efficient material supply.

Edge Filling – Dosing of edge fillers

In addition to honeycomb potting, sandwich components often also have to be sealed and thus reinforced in the edge areas. For this purpose, similar or even identical filling materials are used as those used for filling the honeycombs themselves. Namely, core and edge filling compounds with very low density, which is achieved by enriching the material with hollow spheres.

With our dosing technology, this process can also be automated. The 1-component or 2-component materials are processed gently – without changing their material properties. The material application can be fully automated or semi-automated. Thanks to pulsation-free dispensing, the best results can be achieved with the minimum of effort. This allows you to reduce production times while optimizing production processes at the same time.

Dosing applications in aerospace

Dosing applications in the aerospace industry are subject to the strictest secrecy. Therefore, it is not easy to show you concrete examples here. Possible dispensing applications are insert potting, application of 2-component silicones (incl. degassing) or application of 2-component thermal paste for connecting two components and for heat dissipation.

According to statista, there were nearly 4,100 satellites orbiting the earth at the end of April 2021. In order to guarantee high quality, among other things, the dosing of fluids and pastes onto the individual components must be carried out with absolute precision.

Our dispensing pumps bond solar panels for the satellites, for example. Insert bonding is also implemented with the help of our technology – there are sometimes several thousand inserts per satellite! Not to be forgotten: The electronic components in the satellites. Here, too, our 1-component and 2-component dispensers help to ensure a permanent and high-quality connection – simply and quickly.

Your advantages at a glance:

• High savings potential due to absolute precision and minimal material wastage
• Individual solution finding – adapted to your requirements
• Pre-tests for process validation in the perfectly equipped ViscoTec laboratory – together with you