Method of applying filled polyimide compositions to internal cylindrical surfaces
Abstract
Abstract CERTAIN FILLED POLYIMIDE COMPOSITIONS ARE DISCLOSED IN ADDITION TO A METHOD OF APPLYING THE SAME IN COATINGS OF SUBSTANTIAL THICKNESS TO INTERNAL CYLINDRICAL SURFACES OF COMPRESSOR HOUSINGS, LABYRINTH SEAL BANDS AND THE LIKE. IN A PREFERRED EMBODIMENT A MIXTURE OF A SOLUTION OF POLYIMIDE PRECURSORS AND TALC ARE CENTRIFUGALLY CAST ONTO A METALLIC CYLINDRICAL SURFACE SUCH THAT MOST OF THE SOLVENT IS EVAPORATED AND THE PRECURSORS ARE PATIALLY CURED SO AS TO BE STRUCTURALLY SELFSUSTAINING. THE ROTATION OF THE ARTICLE TO BE COATED IS STOPPED AND THE COATING IS FURTHER CURED UNDER THE PRESSURE OF AN INERT ATMOSPHERE SUCH THAT RESIDUAL SOLVENT AND VOLATILE CURING REACTION BYPRODUCTS ARE EVOLVED WITHOUT BLISTERING THE COATING.
Inventors
- 👤 Keith F Barnhardt
Bibliographic Details
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