Rubber Seals and PTFE in Drones: Critical Components and Material Requirements for Reliability
Different types of drones
Drones, or unmanned aerial vehicles (UAVs), come in various types based on their design and intended applications. The main categories include:
- Multi-Rotor Drones: These are the most common type, featuring multiple rotors (typically 4, 6, or 8) for vertical takeoff and landing. They are used for aerial photography, surveillance, and recreational purposes due to their stability and ease of control.
- Fixed-Wing Drones: Unlike multi-rotor drones, fixed-wing drones have a wing structure similar to an airplane. They can cover larger distances and are more efficient in terms of energy consumption. They are ideal for surveying, mapping, and agricultural monitoring.
- Single-Rotor Drones: These drones resemble helicopters and generally have one large rotor and a smaller rotor on the tail. They can carry heavier payloads and are used for applications like LiDAR scanning and delivery services.
- Hybrid Drones: Combining the features of fixed-wing and multi-rotor drones, hybrid drones can take off and land vertically and then switch to a more energy-efficient fixed-wing flight mode. They are used in applications requiring long-range and endurance, such as environmental monitoring and search and rescue operations.
Structure of Drones
The basic structure of a drone includes:
- Frame: The framework that holds all the components together. It is usually made from lightweight materials such as carbon fiber or aluminum.
- Propulsion System: This includes the motors, propellers, and electronic speed controllers (ESCs) that drive the drone.
- Flight Controller: The onboard computer that manages the drone’s flight. It processes input from sensors and the pilot to control the motors and stabilize the drone.
- Battery: Provides power to the drone. Lithium-polymer (LiPo) batteries are commonly used due to their high energy density.
- Sensors: Includes GPS, accelerometers, gyroscopes, and sometimes cameras or other specialized sensors for navigation and data collection.
- Communication System: Allows the drone to receive commands from the pilot and send back telemetry data. This includes radio transmitters and receivers, and sometimes satellite communication equipment.
Components of drone
Applications and Requirements of Rubber Seals and PTFE in Drones
| Component | Application | Material | Requirements |
|---|---|---|---|
| Rubber Gasket – Battery Compartment | Protect battery from moisture and dust | EPDM Rubber , Silicone/VMQ Rubber | Material Compatibility, Flexibility, Durability, Water and Dust Resistance |
| Rubber Gasket – Motor Housing | Prevent dust and debris | EPDM Rubber, Silicone/VMQ Rubber | Material Compatibility, Flexibility, Durability, Water and Dust Resistance |
| Rubber Gasket – Camera Gimbals | Protect camera components | EPDM Rubber, Silicone/VMQ Rubber | Material Compatibility, Flexibility, Durability, Water and Dust Resistance |
| Rubber Gasket – Sensor Enclosures | Protect sensors | EPDM Rubber, Silicone/VMQ Rubber | Material Compatibility, Flexibility, Durability, Water and Dust Resistance |
| Rubber seal – Bearing Liners | Reduce friction and wear | PTFE | Chemical Resistance, Temperature Resistance, Low Friction |
| PTFE grommet – Cable Insulation | Insulate wires and cables | PTFE | Chemical Resistance, Temperature Resistance, Electrical Insulation |
Variseal / Spring Energised Seals | Low friction and high wear resistance | PTFE | Chemical Resistance, Temperature Resistance, Low Friction |
High speed rotation oil seal | Provide airtight and waterproof sealing | PTFE + Rubber | Chemical Resistance, Temperature Resistance, Low Friction, Non-Reactivity |
PTFE Ring – Rotation/Sliding Components | Enhance movement and reduce wear | PTFE | Low Friction, Wear Resistance, Chemical Stability |
The use of rubber seals and PTFE in drones is crucial for ensuring their reliability and longevity. Rubber seals protect sensitive components from environmental factors. For example, EPDM or VMQ rubber parts can be used for sealing the electronics.
PTFE is valued for its low friction, chemical resistance, and temperature stability.
Here is some detailed explaination for each application:
I. Rubber Components in Power Systems
1. Motor Vibration Dampers
- Function: Absorb vibrations from high-speed motor rotation to prevent instability during flight.
- Material: High-damping silicone rubber (temperature resistance: -50°C to 200°C).
- Design: Honeycomb or corrugated structures for combined shock absorption and heat dissipation.
2. Propeller Rubber Gaskets
- Function: Secure propellers to motor shafts and reduce micro-displacements during rotation.
- Material: EPDM (excellent weather resistance and UV aging resistance).
- Example: DJI Mavic series propellers use EPDM rubber locking rings.
II. Rubber Components in Airframe Structures
1. Landing Gear Shock-Absorbing Pads
- Function: Absorb landing impact to protect internal electronics and structural integrity.
- Material: Foamed polyurethane (adjustable density, ≥80% rebound resilience).
- Innovations:
- Bionic honeycomb structure (30% higher energy absorption efficiency).
- Self-healing rubber (automatically repairs minor cracks).
2. Battery Compartment Seals
- Function: Waterproofing and dustproofing (IP67/IP68 standards).
- Material: Fluoroelastomer (FKM) for oil, chemical, and temperature resistance (-30°C to 200°C).
III. Rubber Components in Avionics
1. Gimbal Shock-Absorbing Balls
- Function: Isolate flight vibrations for stable camera footage.
- Material: Customizable high-elasticity silicone (Shore hardness: 30A–50A).
- Specifications:
- Natural frequency <20 Hz (avoids common drone vibration frequencies of 15–200 Hz).
- Dynamic damping coefficient >0.2.
IV. Specialized Rubber Components for Industrial Drones
1. Fuel Lines for Gas-Powered Drones
- Function: Fuel transfer with oil and low temperature -50℃ resistance.
- Material: Fluorosilicone FVMQ rubber (resistant to aviation fuel).
2. Chemical Tank Seals for Agricultural Drones
- Function: Prevent pesticide leakage and resist corrosion.
- Material: Perfluoroelastomer (FFKM) for acid/alkali resistance (3x lifespan improvement).
- Example: agricultural drones use triple-seal structures.
Please contact OBT for the reliable sealing solution for drones.
Reference Reading:
How to measure the hardness: shore A,B,C,D?
How to measure the density of rubber material?
How to Evaluate the Resistance of Rubber to Oils and Other Solvents？
How to Evaluate the Low-Temperature Performance of Rubber?
How to Evaluate the Resistance of Rubber to Oils and Other Solvents？
How to choose between HNBR and AEM?
How to choose between HNBR and FKM(Viton) for O-Ring/gasket?
How choose Between FKM vs FVMQ?
When to use HNBR and Low Temperature HNBR(LT HNBR)?
Low Temperature FKM Rubber: Ideal for Automotive, Aerospace, and Chemical Processing
