Transcript HVOF - ASETSDefense

Draft JTP for Hydraulic &
Pneumatic Actuators
National Technical Systems / Elwin Jang / 916-392-6163
December 2000
Overview of Joint Test Protocol
• Entire JTP Consists of 3 Parts
– Part I – Material Testing
– Part II – Component or Rig Testing
– Part III – Flight Testing
• This JTP Comprises of Parts I & II
Part I – Significant Information
• WC/Co-Cr Selected as Primary Coating for
Actuators
– WC/Co Can Be Used in Less Corrosive
Environment
– Tribaloy T-400 as Sliding Wear Coating
• Primary Substrates: PH15-5 SS & 4340 Steel
– Secondary Substrates: Ti-10-2-3 Titanium & HP9-430 Steel
Part I – Significant Information
(cont.)
• Finishes for WC/Co-Cr
– Low Stress Grinding: 2-8 Ra (optimum: 2-4 Ra)
– Superfinish: 4 Ra </= with Tp >/= 90% at 0.2
micron
• Finish for T-400
– 8-16 Ra: Unable to Make It Smoother Due to
Softness & Porosity
Part I – Material Testing
• Includes All Tests of Landing Gear JTP
– Don’t Need to Repeat Tests Which Same
Coating/Substrate Combinations are Finished or
Being Conducted
• New Tests: Functional Hydraulic, Immersion,
Stripping
• Includes All Quality Control Tests
– Excludes Tests for Same Coating/Substrate
Combinations That are Finished
Part I – Tests to be Conducted
• Fatigue
• Corrosion – Neutral Salt Fog, 500 Hours
• Functional Hydraulic Rod/Seal – Superfinish, Side
Load, Temp. Extremes, Several Vendors’ Seals
• Immersion
– Potentiometric testing of coating in fluids (?)
Part I – Tests to be Conducted
(cont.)
•
•
•
•
Bond Strength
Bend by Mandrel
4-Point Bend (?)
Piston & Bushing Wear (?)
Part II – Recommended Tests
• Endurance – Withstand cyclic loads & pressure of
anticipated operational life
• Rapid Warm Up Leakage Test: from –40 deg. F to
225 deg. F for 50 Cycles
• Temperature Shock: from –65 deg. F to 275 deg. F
• Salt Fog, MIL-STD-810, Method 509.1, 48 Hours
• Sand & Dust: MIL-STD-810, Method 510.1
• Vibration: MIL-STD-810, Method 514.2,
Procedure 1A
Part II – Recommended Tests
(cont.)
• Friction: Measure force required to pull lubricated
piston rod in the assembled actuator
• Humidity: MIL-STD-810, Method 507.1,
Procedure 1, 100%
• Impulse Cycling: SAE ARP 1383 Withstand
200,000 pressure impulse cycles