Knowledge Hub
01/11/2024
In Focus: Injection Moulding in the Aerospace Sector
As part of our ‘In Focus’ series of articles, we will now profile the role played by injection moulding in the aerospace sector.
We will examine the particular challenges of this manufacturing method when creating automotive parts and components, as well as its many benefits.
We will also look at the various applications that are created for the automotive industry, and we will explore the features of these products, and their specific characteristics.
What is the Role of Injection Moulding in the Aerospace Sector?
Injection moulding plays a critical role in the aerospace sector by producing complex, high-precision components and parts that are essential for aircraft operation and safety. These components can be made from various materials such as thermoplastics, thermosets, and composites, depending on the specific requirements of the application.
Injection moulding offers several advantages in the aerospace sector, including high production efficiency, tight tolerances, and repeatability over large-scale production cycles.
Additionally, injection moulding allows for the creation of lightweight and durable parts that can withstand the extreme conditions and rigorous demands of aerospace applications.
Key Benefits of Injection Moulding for Aerospace Parts and Components
Precision: Injection moulding allows for high levels of precision and repeatability, making it ideal for producing intricate and complex aerospace components with tight tolerances.
Cost-effective: Injection moulding is a cost-effective manufacturing method for high-volume production runs, as it can produce parts quickly and efficiently with minimal waste material.
Material versatility: Injection moulding can be used with a wide range of materials, including thermoplastics, thermosets, and composites, allowing for the manufacture of parts with varying properties and performance characteristics.
Lightweight: Aerospace components need to be lightweight to improve fuel efficiency and overall performance, and injection moulding allows for the production of lightweight parts without compromising strength or durability.
Scalability: Injection moulding can easily scale up or down to accommodate production needs, making it suitable for both small prototype runs and large-scale production volumes.
Examples of Injection Moulded Parts in the Aerospace Sector
Interior components – such as seat components, panels, armrests, and tray tables.
Exterior components – such as fuselage panels, winglets, fairings, and engine cowls.
Air ducts and ventilation systems – cockpit mounted plastic vents.
Lighting fixtures – such as plastic overhead reading lights.
Avionics and electronics components – connectors, insulators, and housings.
Structural components – such as brackets and mounts.
Safety and emergency equipment housings – avionics enclosures, and emergency locator transmitter (ELT) housings.
Trim and finishing pieces – seat armrest covers, control panel bezels, and air vent covers.
What are the Common Features of Plastic Aerospace Components?
High strength-to-weight ratio: Despite being lightweight, plastic aerospace components are usually strong and have a high strength-to-weight ratio, allowing them to withstand high stress and load conditions.
Corrosion resistance: Many plastic materials used in aerospace components are resistant to corrosion, making them suitable for use in harsh environmental conditions.
High temperature resistance: Plastic aerospace components are designed to withstand high temperatures typically experienced in aerospace applications.
Good insulating properties: Plastic materials have good insulating properties which make them suitable for use in electronic and electrical components in aerospace applications.
Ease of fabrication: Plastic materials are often easier to fabricate and mould into complex shapes compared to metals, making them a popular choice for aerospace components.
Main Challenges When Injection Moulding Parts for the Aerospace Sector
Material selection: Aerospace parts often require high performance materials which can withstand extremities such as high temperatures, pressure, and resistance to chemicals. Selecting the right material is crucial for ensuring that the part meets its requirements.
Tight tolerances: Aerospace parts often have strict dimensional tolerances that must be met to ensure proper fit and functionality. Injection moulding can present challenges in achieving these tight tolerances consistently.
Complex geometries: Aerospace parts can have intricate and complex geometries that may be difficult to replicate accurately through injection moulding. Ensuring that the mould design and process parameters are optimised for these complex shapes is essential.
Quality control: Ensuring the quality and reliability of aerospace parts is critical for safety and performance. Injection moulding processes must be closely monitored and controlled to prevent defects and maintain consistent quality.
Regulatory compliance: Aerospace parts are subject to rigorous regulatory standards and certifications. Injection moulding processes must adhere to these standards and undergo thorough testing and validation to ensure compliance.
Cost considerations: The need for specialised materials, complex geometries, and stringent quality standards can make aerospace parts costly to manufacture. Balancing cost considerations while meeting performance requirements can be a challenge.
What are the Key Injection Moulding Plastics for the Aerospace Sector?
Common plastics used in the injection moulding of aerospace components and parts include:
Polycarbonate (PC) – Known for its high impact resistance and transparency, making it ideal for aircraft windows and interior components.
Polyetheretherketone (PEEK) – A high-performance thermoplastic with excellent mechanical properties and resistance to heat. It can be used to manufacture engine components, electrical connectors, and structural parts.
Polyamide (PA) – Also known as nylon, polyamides are strong, lightweight, and have good chemical resistance, making them ideal for manufacturing fuel tanks, ducts, and fasteners.
Acrylonitrile Butadiene Styrene (ABS) – A thermoplastic known for its toughness and resistance to high temperatures, ABS is ideal for interior components, seat parts, and panels.
Polyphenylene Sulfide (PPS) – A high-performance thermoplastic with excellent chemical and heat resistance, making it suitable for engine components, electrical connectors, and structural parts.
Polyethylene (PE) – A lightweight and flexible thermoplastic with good chemical resistance, making it suitable for packaging materials and insulation components.
Polypropylene (PP) – A versatile thermoplastic with good impact strength and chemical resistance, making it ideal for interior components, ducts, and fuel tanks.
