The problem to increase the reliability of aircrafts and to reduce the cost factor of putting the load into space has become acute with space development. The main units of rocket propulsion system are liquid-propellant engines (LPE) which constitute 20-40 % of the overall cost of a spaceship. This article considers the eddy-current technique of thickness inspection of functional galvanic coatings of parts made of nonmagnetic and weak-magnetic heat resistant conductive materials. First of all, these are nickel, copper and silver coatings to solder different parts of LPE including honeycomb constructions. The difficulties of thickness inspection in this case come from: 40 % changes in specific conductivity and magnetic permeability within one part; local inspection for the area is not more than 5 mm2; required measurement accuracy is not more than 8-10 %. This made us develop a new methodical approach to designing of NDT means and metrological assurance. The new eddy-current thickness gauge which helped us to solve the problem of thickness inspection at different combinations of base and coating materials is reported. The study also discusses the features of metrological assurance for the inspection process with the use of reference and industrial standards, which were produced by selective gravimetric method, and on-site samples. As a result we developed a unique technique for the thickness inspection of different coatings including nickel coatings to be soldered on the parts of modern LPE.
Inspection features of constructive technological coatings of composite elements for new generation liquid propellant engines (LPE)
Untersuchung der Merkmale von konstruktiven technologischen Beschichtungen von Verbundelementen für eine neue Generation von Flüssigtreibstoffmotoren
2006
5 Seiten, 5 Bilder
Aufsatz (Konferenz)
Datenträger
Englisch
Liquid-Propellant Rocket Engines
Springer Verlag | 2012
|History of liquid propellant rocket engines
TIBKAT | 2005
|VARIABLE-THRUST LIQUID PROPELLANT ROCKET ENGINES
AIAA | 1963
|