Cryogenic treatment of mixed loads

Abstract

A process for treating mixed loads of tools and/or parts which incorporates an optional pre-heat phase, a cryogenic phase, and an optional post temper phase.

1 . A method for deep cryogenic tempering of mixed loads of tools and/or parts in the same cryogenic processing chamber, the method comprising the steps of: (a) determining if any of the tools and/or parts of the mixed load require pre-heating; (b) placing any tools and/or parts requiring pre-heating in an oven and raising the temperature to approximately 300 degrees F.; (c) holding the tools and/or parts requiring pre-heating at approximately 300 degrees F. for a period of time approximately equivalent to 1 minute of pre-heat at approximately 300 degrees F. for each inch of cross-section thickness; (d) placing the tools and/or parts that required pre-heating immediately after pre-heating into a cryogenic processing chamber containing tools and/or parts that do not require pre-heating that are at ambient; (e) cooling the mixed load of tools and/or parts at a descent rate of approximately 1 degree F. per minute until the temperature of the tools and/or parts is approximately −214 degrees F.; (f) maintaining the tools and/or parts at a temperature of −214 degrees F. for a period of time, the hold time being a function of the total mass in the cryogenic processor; (g) cooling the mixed load of tools and/or parts at a descent rate of approximately 1 degree F. per minute until the temperature of the tools and/or parts is approximately −246 degrees F.; (h) maintaining the tools and/or parts at a temperature of −246 degrees F. for a period of time, the hold time being a function of the total mass in the cryogenic processor; (i) cooling the mixed load of tools and/or parts at a descent rate of approximately 1 degree F. per minute until the temperature of the tools and/or parts is approximately −289 degrees F.; (j) maintaining the tools and/or parts at a temperature of −289 degrees F. for a period of time, the hold time being a function of the total mass in the cryogenic processor; (k) cooling the mixed load of tools and/or parts at a descent rate of approximately 1 degree F. per minute until the temperature of the tools and/or parts is approximately −300 degrees F.; (l) maintaining the tools and/or parts at a temperature of −300 degrees F. for a period of time, the hold time being a function of the total mass in the cryogenic processor, (m) raising the temperature of the mixed load of tools and/or parts to a range of approximately 0 degrees F. to 85 degrees F. at an ascent rate, the ascent rate being a function of the total mass of tools and/or parts in the cryogenic processing chamber; (l) determining if any of the tools and/or parts require a post temper cycle; (n) placing any tools and/or parts requiring a post temper cycle into at least one oven according to tempering temperature and cross-sectional thickness; (o) raising the temperature in the at least one post tempering oven to the a prescribed post tempering temperature approximately in the range of 250 degrees F. to 400 degrees F. for a post temper time, the post temper time approximately equivalent to 1 hour of post tempering at the tempering temperature for each inch of cross-section thickness; (p) lowering the temperature of the tools and/or parts to ambient at a cool down rate; (q) raising the temperature of the tools and/or parts to the prescribed temperature approximately in the range of 250 degrees F. to 400 degrees F. at an ascent rate; (r) maintaining the temperature of the tools and/or parts at the prescribed temperature approximately in the range of 250 degrees F. to 400 degrees F. for a post temper time; (s) lowering the temperature of the tools and/or parts to ambient at a cool down rate; (t) raising the temperature of the tools and/or parts to the prescribed temperature approximately in the range of 250 degrees F. to 400 degrees F. at an ascent rate; (u) maintaining the temperature of the tools and/or parts at the prescribed temperature approximately in the range of 250 degrees F. to 400 degrees F. for a post temper time; and (v) lowering the temperature of the tools and/or parts to ambient at a cool down rate. 
     
     
         2 . The method of  claim 1 , wherein an optional step can be inserted between steps (d) and (e), the optional step comprising: cooling the mixed load of tools and/or parts at a descent rate of approximately 1 degree F. per minute until the temperature of the tools and/or parts is approximately −160 degrees F.; and maintaining the tools and/or parts at a temperature of −160 degrees F. for a period of time, the requirement for inserting said optional step being cross-section thickness of tools and/or parts in the cryogenic processing chamber, and hold time being a function of the total mass of the mixed load of tools and/or parts in the cryogenic processor. 
     
     
         3 . The method of  claim 1 , wherein the tools and/or parts is from the set consisting of drill bits, reamers, end mills, progressive dies, punch dies, press dies, forge dies, mill hammers, extrusion dies, dummy blocks for extrusion equipment, pillow blocks, bearings, pellet dies, granulators, grinding plates, circular slitters, cutters, hobs, shear blades, band saw blades, taps, broaches, roll dies, carbide inserts, spot welding tips, welding nozzles, welding tips, welding feeders, welding guides, welding tubes, cutting torch tips, cutting torch nozzles, electric motor parts, saw blades configured for brick, saw blades configured for pavers, saw blades configured for block, saw blades configured for marble, saw blades configured for granite, saw blades configured for quartz, saw blades configured for tile, saw blades configured for cured concrete, saw blades configured for green concrete, saw blades configured for asphalt, saw blades configured for demolition work, saw blades configured for rebar steel, saw blades configured for tuck pointing, cup grinders, coring bits, concrete drills, grader blades, wear edges for bucket loaders, wear edges for scrapers, wear edges for graders, wear edges for snow plows, one piece track gears, multi-piece track gears, scarifier teeth, ripper teeth, road milling bits, jack hammer bits, crack grinders, crack grinder rods, trencher chains, roller chain, stabilization tines, blow bars, hammer mill hammers, hammer mill hammer rods, pumps, chain saw chains, chain saw sprockets, rope saws, nitrogen knives for agriculture, coring bits, drills, bucket teeth, soil mixing tines, soil mixing blades, tire shredding tools, metal shredding hammers, metal shredding hammer rods, metal shear tools, push rods, steel rocker arms, aluminum rocker arms, valves, valve springs, camshafts, crankshafts, steel connecting rods, aluminum connecting rods, steel pistons and rings, aluminum pistons and rings, crankshafts, bearings, steel heads, aluminum head, steel blocks, aluminum blocks, brake drums, brake rotors, brake pads, spark plugs, transmission gears, red end gears, axles, timing chains, timing gears, rear sprockets, torque converter stators, golf clubs, golf balls, aluminum baseball bats, aluminum softball bats, racket strings, fishing line, musical instruments, electronic cables, circuit boards, razors with integrated blades, razor blades, panty hose, welded components, rubber impregnated Nomex, dental tools, light bulbs, guitar strings, and honing stones.