Case study · Aerospace
For one of the leading thermal-actuator manufacturers in the United States, supplying the world's leading aerospace manufacturers.
The client had to supply actuator diaphragms compliant with Skydrol hydraulic fluid, surviving 200,000 cycles while immersed — with no guidance on which material would work.
After evaluating several elastomers, Harkesh proposed an EPDM formulation, developed the plug and diaphragm, and cleared testing in the first attempt. The parts now fly on the Boeing 787 Dreamliner and Airbus 320.
Key outcome:
A Skydrol-compatible EPDM diaphragm and plug, approved on the first attempt — now in service on the Boeing 787 Dreamliner and Airbus 320.
The challenge
The client had to supply diaphragms to one of the world's leading aerospace manufacturers. The diaphragm's raw material had to be compliant with Skydrol fluid, and the end client needed the actuators to work successfully for 200,000 cycles while immersed in Skydrol.
Crucially, our client did not have any information on what material would be best suited for this development.
Our approach
After considering various materials including HNBR, FVMQ and Butyl, an EPDM formulation was proposed by Harkesh Rubber.
We developed samples of both the plug and the diaphragm and submitted them for testing against the demanding Skydrol-immersion requirement.
The results
First time right
Cleared first attempt
The plug and diaphragm cleared testing and were approved in the very first attempt.
In service
Boeing 787 & Airbus 320
The parts are now in use on the Boeing 787 Dreamliner and Airbus 320 aircraft.
Our quick development process and successful testing in the first attempt helped our client win the contract from the end client. The parts are now in use on the Boeing 787 Dreamliner and Airbus 320.
Materials & application
Questions, answered
The part had to resist Skydrol, an aggressive phosphate-ester hydraulic fluid, through 200,000 immersed cycles. After evaluating HNBR, FVMQ, Butyl and others, an EPDM formulation gave the best combination of Skydrol compatibility and fatigue life.
Skydrol is a phosphate-ester aviation hydraulic fluid that attacks many elastomers. A Skydrol-compatible compound resists swelling and degradation, so the diaphragm keeps sealing and flexing reliably while immersed.
The qualified EPDM plug and diaphragm are in service on thermal actuators used on the Boeing 787 Dreamliner and Airbus 320.
Address
Mumbai Office: Harkesh Rubber LLP, 108, Adarsh Industrial Estate, Sahar Road, Chakala, Andheri (East), Mumbai 400099
General Enquiries
contact@harkeshrubber.com
Business Phone
+91-22-40060400
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