Abstract: A centralizer apparatus has been developed which, in one aspect, has a tubular body with an exterior surface, a collar movably emplaced around the tubular body and movable longitudinally thereon, a plurality of spring bows, each spring bow having a first end spaced apart from a second end, each spring bow biased outwardly from the tubular body, the first ends connected to the tubular body, the second ends connected to the first collar, so that upon movement of the first collar the spring bows move toward the tubular body. In one aspect the collar is connected to bottom ends of the spring bows and is initially movable to abut a stop on the tubular body so that from that point on the spring bows are pulled into another tubular, e.g. casing, as the centralizer apparatus moves down into the casing. In another embodiment two movable collars are used, one at each end of the spring bows.

Abstract: Disclosed is a refined and alloyed martensite-free cast steel abrasive material and method of making the same. The abrasive material is either shot or grit and has a composition which includes carbon in about the range of 0.60 to 1.20 percent by weight, silicon in about the range of from 0.30 to 1.50 percent by weight, sulphur in about the range of from 0.0 to 0.1 percent by weight with the remainder substantially all iron, trace elements and impurities. The substantially martensite-free micro-structure is characterized by the presence of one or more of the group consisting of lower bainite, upper bainite, pearlite or ferrite and mixtures thereof, thus providing a more ductile abrasive particle of improved wear resistance.

Abstract: Disclosed is a method of producing a versatile as-cast steel shot having a substantially fully martensitic structure and corresponding full hardness which permits eliminating intermediate steps of heat treating to harden and subsequent drying in producing steel shot having a tempered martensitic structure or in producing steel grit.The method includes steps of charging, melting, refining, and pouring. The pouring step is accomplished by directing a stream of the refined molten steel through a stream of water under pressure and into a fluid quenching bath. The refined steel comprises: carbon in about the range of from 0.6 to 1.20 per cent by weight; manganese in about the range of from 0.50 to 2.26 per cent by weight; silicon in about the range of from 0.3 to 1.80 per cent by weight; sulphur in about the range of from 0.0 to 0.1 per cent by weight; phosphorous in about the range of from 0.0 to 0.1 per cent by weight; boron in about the range of from 0.0 to 0.