Auxiliary Power Unit (APU) housings (found on aircraft, large trucks, or mobile generators) are highly stressed components. They must seal hot lubricants and combustion byproducts while enduring constant high vibration, severe thermal cycling (from start-up to shutdown), and often contain dissimilar metals like aluminum and steel. A leak in an APU housing compromises oil supply, risks fire, and leads to expensive component replacement and grounding of equipment.
Don’t let rigid, cracking seals compromise the complex, high-maintenance environment of your APU.
INCURE HeatGrip™ 508 Flexible Anaerobic Flange Sealant for Aluminum
APU components often rely on lightweight aluminum casings bolted to rigid steel parts, creating movement due to thermal expansion. While the HeatGrip™ 503 is highly rigid, the high vibration and complexity of APUs necessitate a flexible seal that is aluminum-compatible and easy to remove. The INCURE HeatGrip™ 508 is ideal, providing superior flexibility, chemical resistance to hot oil, and reliable sealing on passive metals.
| Feature & Benefit | Technical Insight for APU Housings | Conversion Value |
| Excellent Flexibility | Cures to a tough, elastic seal that absorbs continuous high vibration and accommodates the differential expansion of aluminum and steel components. | End the Vibration Threat: Get a seal that moves with the APU, ensuring integrity during intense operation. |
| Aluminum Compatibility | Specifically formulated to cure reliably and safely on passive metals like aluminum, without the need for primers common on reactive APU casings. | Protect the Housing: Ensure the sealant works without risk of corrosion on sensitive aluminum components. |
| Superior Fluid Immunity | High chemical resistance ensures the seal is unaffected by hot synthetic lubricants, fuel, and exhaust gases, preventing degradation. | The Absolute Barrier: Trust a permanent seal that won’t break down or contaminate the APU’s oil system. |
| Easy Disassembly | Designed for strong sealing yet allows for non-destructive part separation, simplifying future overhauls and maintenance procedures on complex housings. | Service Smarter: Seals tightly for duty, but permits easy removal for high-frequency maintenance cycles. |
Application Steps: Sealing APU Housings for Permanent Integrity
Preparation (Critical Cleaning): Thoroughly clean both flange faces—remove all previous sealant, gasket material, and all traces of APU oil/fuel. Use a powerful degreasing solvent (like acetone or industrial cleaner) and wipe until the metal surfaces are perfectly dry and spotless.
Application: Apply a continuous, thin bead of HeatGrip™ 508 onto one flange face, circling all bolt holes. Use a roller or spreader to create a uniform, thin film across the entire mating surface.
Assembly: Immediately mate the housing segments (within 5 minutes). Torque the bolts incrementally to the manufacturer’s specified pattern and value to ensure even clamping pressure.
Curing Time (Mandatory): Allow a full 24 hours for the sealant to achieve its final strength and full chemical resistance before introducing oil or subjecting the APU to operational heat and vibration.
Stop risking leaks and maximize the operational availability and longevity of your auxiliary power units.