Showing papers by "Bethlehem Steel published in 1975"

Effect of continuous cooling on the morphology and kinetics of pearlite

Abstract: The effect of variations in cooling rate on the morphology and kinetics of pearlite was studied and was contrasted with the isothermal and isovelocity modes of transformation. It was found that continuous cooling suppresses the pearlite transformation to a lower reaction temperature where finer nodule diameters and interlamellar spacings are produced. Growth rates in continuous cooling were in agreement with those for the isovelocity and isothermal transformations, the rate-controlling process for growth in the temperature range studied being volume diffusion in all three cases. The relationship between interlamellar spacing and undercooling was found to be SΔT = 8.02 × 104A K, regardless of the mode of transformation.

Fatigue Life Extension of Riveted Connections

Abstract: The paper describes a fatigue test program that studied the effectiveness of rehabilitation by replacement of rivets with high-strength structural bolts in critical or fatigue-damaged locations as a more economical alternative to replacement of entire members. Constant amplitude fatigue tests and variable amplitude service simulation tests of full-scale model ore bridge joints and constant amplitude tests of joints removed from an ore bridge showed that rehabilitation of fatigue-damaged members by fastener replacement increases fatigue life two to six times. It was found that cumulative damage analysis of the constant amplitude tests conservatively predicts the variable amplitude test phenomena. The effect on fatigue life extension of increasing bolt tension above the minimum value accepted in present specifications and the effect of crack length up to l in. (25 mm) long or both, at rehabilitation were found to be of secondary importance.

Coke oven larry car coal restricting insert

Abstract: A removable insert is placed in the collar of larry hoppers to restrict the flowing coal to a column having a dimension less than the interior width of the coking chamber and charging hole to provide space for exhausting charging gases.

Coated sheet metal and method of forming products therefrom

Abstract: Sheet metal having a partially cured organic thermosetting coating thereon and method of forming drawn and ironed seamless containers therefrom.

Effects of zinc coatings on the stress corrosion cracking and hydrogen embrittlement of low-alloy steel

Abstract: The effects of electroplated and hot-dip zinc coatings on the fracture of low-alloy steel AISI 4140 bars tempered to hardnesses in the range Rc 33 to 49 were studied. Either electroplated or hot-dip zinc coatings decrease resistance to stress corrosion cracking,i.e., they reduceKsc, the threshold stress intensity for stress corrosion cracking in 3.5 wt pct NaCl solution. AboveKscelectroplated-zinc coatings do not appear to affect the crack-growth rate, although the incubation period prior to the onset of crack growth is reduced. Hot-dip zinc coatings increase stress corrosion crack growth rates slightly because of the additive effect of internal dissolved hydrogen. Hot-dip zinc coatings reduce the critical stress intensity for fracture in the absence of a corrosive environment because of embrittlement by internal hydrogen which is released from traps during hot-dip coating and confined by the inter metallic coatings which form on the steel surface in the hot dip bath. A simple fracture mechanics analysis indicates that either increasing diameter or the presence of a zinc coating lowers the critical hardness at which the stress corrosion cracking of structural bolts can occur.

Behavior of Cold-Rolled Stainless Steel Members

Abstract: Results obtained from a research project dealing with the structural behavior of cold-formed members of cold-rolled stainless steel are presented. The distinctive mechanical properties include anisotropy, nonlinear and unsymmetrical stress-strain relationships in tension and compression, and the pronounced effect of cold working. The post-buckling behavior of thin compression elements stiffened along one or both unloaded edges by thin webs has been found to agree with Koiter’s theory, with von Karman’s relationship on effective width, as modified by Winter for carbon steel, as the lower bound. Using an iterative numerical procedure, the flexural strength and deflection of thin-walled cold-rolled stainless steel beams can be predicted accurately. A brief analysis on column behavior is also presented. Design methods taking into account the material characteristics and the post-buckling strength of the thin compression elements of these structural members are recommended.

A Simulation-Based Scheduling and Management Information System for a Machine Shop

Abstract: This paper describes the design, working, performance, costs and benefits of a computerized scheduling and management information system that has been developed for a large, generalized m/n machine shop which had previously been a bottleneck facility in the Cast Roll Manufacturing complex of Bethlehem Steel Corporation. A flexible discrete-event simulation model, at the heart of the computer system, generates two types of schedules: Planning Schedules for making long- and medium-term planning and operating decisions, and Production Schedules for sequencing approximately 1,000 rolls on 40 machines on a day-to-day basis. A number of supporting programs perform data management, file management, and report-generation functions. Data-collection functions are deliberately performed manually to avoid the high costs associated with automatic data-collection equipment normally used in large computer systems. The computer programs are run in a time-sharing environment. A cathode ray tube and a medium-speed printer ...

Regeneration of alkanolamine absorbing solution in gas sweetening processes

Abstract: A catalytic amount of ammonia or ammonium compounds are utilized to prevent deterioration of alkanolamines employed in gas sweetening processes. The ammonia is added either to the sour gas or the absorbing solution and acts to suppress thiocyanate formation during absorption.

Injection mold with ultra sonic gating means

Abstract: A mold is provided with a pair of cavities interconnected by a runner to a common entry point. One of the cavities is gated whereby plastic may be injected into this cavity only by applying ultrasonic energy to the gate.

Method of hot reducing ferrous and ferrous alloy products with composite martensitic nodular cast chill iron rolls

Abstract: This invention is directed to a method of hot reducing ferrous and ferrous alloy products, such as plates, strip, bars and rods, where such products are heated to temperatures in excess of 1900° F and subsequently reduced at temperatures within the range of about 900° and the initial heating temperature. More particularly, this invention relates to the method of effecting said hot reducing at such temperatures by means of composite, martensitic, nodular graphite chill cast iron rolls. Such rolls are characterized by (1) an average surface hardness of at least about 76 Shore-C, (2) a thermal-crack-resistant chill cast surface portion consisting essentially of, by weight, about 3.00% to 3.70% carbon, about 0.35% to 1.25% manganese, about 1.0% to 2.0% silicon, about 3.75% to 5.75% nickel, about 0.75% to 1.35% chromium, about 0.40 to 1.10% molybdenum, about 0.3% to 0.08% magnesium, balance iron and incidential impurities, and (3) a core portion comprising a ferrous alloy.

Improved J c in mechanically fabricated Nb 3 Al wires and ribbons

Abstract: Nb 3 Al wire which is essentially all A15 may be fabricated by powder or rod composite techniques, with subsequent reaction and ordering anneals. Several of the previously existing problems, including aluminum loss and Kirkendall porosity, have been identified and solved, and transverse-field critical current densities well into the 105amp/cm2range can be produced. However, reproducibility of the critical current density seems to depend on reproducible control of grain size, which we have not as yet achieved. The internal oxidation techniques which succeed for Nb 3 Sn do not appear to work for Nb 3 Al, for several reasons. A possible solution to the grain size problem, and to the problem of manufacture of Nb 3 Al in stabilized form, is to lower the initial reaction temperature. To achieve the latter we have reduced the scale of the elemental composite to a required diffusion distance of about 3000 A. before reaction. We were thus able to produce substantial quantities of A15 at 1100°C, but for several reasons (see text) we believe finer composites will be necessary.

Deep hardening machinable aluminum killed high sulfur tool steel

Abstract: A low-alloy tool steel, for dies and molds, is deep hardening and highly machinable in the hardened condition. The steel is a water-quenched composition containing boron, sulfur, at least 0.020% aluminum, and a minimum of hardening agents including chromium and molybdenum. The method of producing such steel is disclosed.

Data communication system having bidirectional station interfaces

Abstract: Digital data, in the form of serial station bit frames which exclude protocol information, are communicated bidirectionally over a plurality of serial transmission channels to peripheral devices in a digital process control system. Data enters and leaves a process control computer input-output section serially in response to software-generated control signals. Serial-to-parallel station interfaces are located along each channel. Each interface has a multifunctional shift register responding to the control signals to provide not only bidirectional data flow through each station, but simultaneous parallel loading of each peripheral device. One software control logic arrangement eliminates modems and portions of hardwired data flow control logic elements in each station interface, yet operates with a station bit frame which excludes protocol information. Also provided are true interrupt capability at each interface; verification of every bit of input and/or output of each station interface; diagnostics.

Portable instrument for recording electrical load current and operating duration

Abstract: Self-contained portable recording instrument is particularly useful at field sites for recording the magnitude of both welding current and operating duration. A second embodiment is adapted to record the magnitude of welding current, voltage and operating duration. Strip chart records provide analysts with means for determining operator incentive pay when working on field assignments. Records enable determining the quality and duration of actual welds, as well as the occurrence of operator-simulated welding time.

Process for preparing ores for concentration

Abstract: IMPROVED PROCESS FOR PREPARING ORES FOR CONCENTRATION Abstract of the disclosure A process for preparing ores for separation and recovery of minerals from gangue wherein crushed particles of ores are subjected to a series of sequential dry impact grinding steps in a plurality of dry centrifugal impact grinding mills to produce a product containing liberated minerals and gangue at a coarser than normal liberation size. The product can be treated by mineral separtation and recovery processes to separate the minerals from gangue and recover the minerals as a usable concentrate of a predetermined grade. The efficiency of hte mineral separation and recovery processes, for example, froth flotation, magnetic separation, gravity separation, and the like, is improved. The process makes the recovery of minerals more economical than prior preparation processes.

Coke quenching car closure mechanism

Abstract: A coke quench car having a slanted bottom and discharge opening in one wall is provided with a movable grate at the discharge opening to drain water and retain coke. A door outboard of the grate closes the discharge opening in a substantially liquid-tight condition and accumulates quench water in the car to submerge the coke. Means are provided for selectively opening the door to drain only water at the quench station and for later opening the grate to discharge the quenched coke at the coke wharf. A second embodiment provides a tilting bottom coke car with a first sealing means for sealing the car in substantially liquid-tight condition to accumulate water and submerge the coke. A second sealing means are provided to permit the floor to be tilted to a liquid discharge position to drain only water. Means are provided for tilting the floor between an open and closed and intermediate liquid discharge position.

Method of continuously casting molten metal

Abstract: A method of introducing molten metal, especially steel into a rectangular, open-ended continuous casting mold. The method is especially suitable for the continuous casting of high quality steel blooms and billets. The molten metal is introduced beneath the surface of a pool of molten metal contained in the mold from a submerged pouring nozzle as four fixed streams oriented with respect to the mold walls so as to produce a circulatory flow of molten metal around the perimeter of the mold.

Halogen tin electrodeposition bath sludge treatment

Abstract: A process for the extraction and recovery of hydrated stannic oxide and alkali metal ferrocyanide from the sludge formed in a halogen tin electrodeposition bath is described. The process comprises dissolving the ferrocyanide compounds and the tetravalent tin compounds present in the sludge in an alkaline medium, removing any insoluble materials, precipitating hydrated stannic oxide from the solution by neutralization of the solution, and separating the hydrated stannic oxide from the solution which then contains ferrocyanide ion together with acid and base counterions.

Method and apparatus for protecting basic refractory shapes in a basic oxygen furnace

Abstract: Basic refractory shapes in selected critical wear areas of a working lining in a basic oxygen furnace are protected from spalling due to thermal shock during "burn-in" and initial operation of the working lining and during the early part of a furnace campaign. A plurality of securing means comprising relatively thin, elongated, flat, generally rectangular anchors are positioned in selected joints in the working lining during installation. The anchors extend a distance beyond the hot faces of the working lining. A reticulated reinforcing means comprising a metallic grid is fastened to the anchors in spaced relationship to the hot faces. A layer of a pulverulent basic refractory material having a thickness sufficient to cover the anchors and metallic grid is sprayed over the working lining in the critical wear areas. The layer of sprayed material provides an effective insulation over the basic refractory shapes in the critical wear areas during "burn-in" of the working lining in the furnace.

Tunnelized burner for panel type furnace

Abstract: Heating apparatus for a continuous moving strand characterized by a plurality of pairs of opposed spaced apart heating panels between which said strand is caused to move, where at least one of said panels consists of a single burner recessed from the panel wall adjacent the moving strand.

Method for preparing dry-collected fume for use in metallurgical furnaces

Abstract: A method for preparing strong, stable "green" balls of dry-collected iron-bearing fume, which contains not less than about 8% combined amount of lime (CaO) and magnesia (MgO). The fume is charged to a balling device where there is added to the fume a quantity of water equal to both the stoichiometric amount required to completely hydrate such lime and magnesia and to produce in the green balls a water content between about 7% - 12%. The residence time of the fume on the balling device is not less than about 8 minutes.

Method of reducing iron oxide

Abstract: Iron ore particles are partially reduced by passing through a rotary kiln countercurrent to flowing hydrogen and carbon monoxide. The partially reduced ore is then fed into a plasma arc torch wherein the reduction is completed. The off-gas from the arc torch is reacted with methane to reform the water vapor in the off-gas into hydrogen and carbon monoxide which are used to partially reduce the iron ore particles in the rotary kiln.

Studies on detergent phosphate replacements: I. Aerobic biodegradation of sodium 2‐hydroxyethyliminodiacetate

Abstract: The biodegradation of sodium 2-hydroxyethyliminodiacetate, a potential substitute for detergent phosphate, has been studied under aerobic conditions. The biodegradation of this material has been demonstrated in both river water die-away tests and in an activated sludge system which approximated an actual municipal sewage treatment plant. In the latter instance, degradation in excess of 90% has been observed in less than 6 hr.

Method for vacuum metal cladding

Abstract: A method of bonding strips of metals by a combination of electron beam heating, cleaning and rolling in a vacuum.

Method for retaining material within a plunging bell

Abstract: A method and device for charging and supporting containerized reagents within a plunging bell including positioning the reagents within a plunging bell and supporting the reagents with a support member depending from the sidewalls of the plunging bell and extending across the bottom opening beneath the sidewalls of the plunging bell.

Nonperishable direct enameling steel and method for producing same

Abstract: A steel composite exhibiting both corrosion resistance and direct enamelability is produced by coating the steel substrate with a layer of between about 1 and about 15 grams per base box of a synthetic ester selected from the group consisting of pentaerythrityl dioleate and pentaerythrityl tetraoleate.