Abstract: A refurbished turbine vane and method of producing the same. Used turbine vanes are cleaned, annealed and slotted adjacent their ends, after which the cooling passages are welded closed and all cracks welded over, on both leading and trailing edges. The trailing edge, for a vane having a short chord, is built up by welding along its full length with an alloy wire, after which the slots that were cut adjacent the ends are closed, also by welding. Then the worn surfaces of the vane are built-up by a plasma spray process, using a metal powder with added silica, to a thickness as great as 30 to 40 thousandths of an inch. The built-up vane is then sintered and thereafter surface finished to conform to the original contour of the blade when new. The cooling holes are finally recut, and the vane polished as required and inspected.

Abstract: Leaks in a vessel or pipe line and the like adapted for containing a fluid re sealed by means of a polymerization system comprising a catalytically polymerizable organic monomer and a polymerization catalyst therefor, by first providing a catalytically effective amount of the catalyst at the situs of the leak and then supplying vapor of the monomer to the interior of the vessel under sufficient pressure and for a sufficient period of time to permit contact thereof with the catalyst to effect formation of a polymer providing a solid seal at the situs of the leak.

Abstract: This specification describes a process and apparatus for closing leaks and spraying a sealant composition to interior walls of an underground gasoline tank such as is used in retail gasoline service stations. A gas tank suspected of leaks is emptied of stored gas and purged with compressor air applied thru a valve control and pipe conduit threadly inserted in the conventional fill pipe of the tank. The pipe conduit includes a means defining an aperture at the lower extremity of the conduit which extends into the tank interior. An explosion safety level meter is attached to the pipe conduit for providing a humanly detectable signal of the environment within the tank. An excavation enables a craftsperson to cut an access port through the tank wall for entering the tank interior, cleaning-up residue, sandblasting the interior walls, and spraying a sealant composition of thixotropic polyester resin and a catalyst onto the sandblasted walls.

Abstract: Immersion of semiconductor devices, particularly diodes, having a defective tin plating thereon in a solution of 5 - 20 percent by weight trichloroacetic acid, 0.1 to 5 percent by weight of a compound selected from the group consisting of cationic, anionic, and nonionic surfactants and the balance water effectively removes the tin therefrom. The process is effective at room temperature but preferably is performed at approximately 100.degree. C.

Abstract: Complete coating or localized repair and replacement of a diffusion aluminide coating applied to the surface of an article is attained through use of a powdered Fe-Al alloy as a source of aluminum. In another aspect, more accurate control of a coating method, such as for aluminide diffusion coating, is achieved when a source powder is provided in a layer, such as a tape, preferably by combining the powder with a binder which decomposes substantially without residue upon heating.

Abstract: Disclosed is a method for repairing an electrostatographic photoreceptor comprised of a conductive substrate with a uniform layer of selenium on its surface. Scratches in the selenium layer of a depth less than its total thickness are filled with a photoconductive composite as repair material. When the combination of materials forming the composite are selected so as to provide discharge characteristics similar to those of selenium, the repaired photoreceptor will provide copies in which printout in the repaired areas is of the same quality as in the non-damaged areas.

Abstract: In the pack diffusion coating of chromium into the surface of a superalloy, the formation of undesirable oxide inclusion is reduced when the diffusion coating pack contains at least about 3% Ni.sub.3 Al. Also the formation of alpha-chromium is reduced when the pack diffusion is carried out in a retort effectively not over five inches in height. Pack aluminizing in the presence of chromium makes a very effective aluminum-and chromium-containing top coating over platinum plated or platinum coated nickel-base superalloys. Aluminized nickel can also have its aluminum attacked and at least partially removed with aqueous caustic to leave a very highly active catalytic surface. Pack diffusion can also be arranged to simultaneously provide different coatings in different locations by using different pack compositions in those locations. An aluminizing pack containing a large amount of chromium provides a thinner aluminized case than an aluminizing pack containing less chromium, or less chromium and some silicon.

Abstract: Metal, carbon, or other original surfaces of articles, such as pneumatic and hydraulic cylinders, having scored or marred surfaces can be rehabilitated by applying to them a composition consisting essentially of a mixture of powdered molybdenum disulfide and epoxy resin, curing the resin, and removing excess material. The coating is as hard as steel, has lubricative action, and can withstand high temperatures.

Abstract: Leaks in closed cooling systems containing an aqueous medium as the coolant, are sealed by electroless deposition of a metal or metal containing compound from a water soluble, easily reducible metal compound. A complexing agent may be added to the coolant to assist in solubilizing the easily reducible metal compound. In one embodiment, the reducible metal compound is formed in situ by attacking the conduit walls of the cooling system so as to form solubilized compounds, or compounds which can be solubilized by addition of suitable complexing agents.

Abstract: Water-damaged electrical equipment is rehabilitated by treatment with a bath comprising a paraffinic oil, a polymethyl aromatic compound, a salt formed from the reaction of an N-alkyl polymethylenediamine and a dimer acid, and an inert organic solvent.