Search

This paper considers the development, plant implementation and application of X-ray diffraction (XRD) analysis and near infrared (NIR) analysis for reliable quantitative mineralogical ore profiling at several copper mines. This allows ore routing to be optimised, ore-type profiling improved, swelling clay identified so that permeability losses in heap leaching can be rectified, conveyor chute plugging prevented, flotation problems avoided and tailings thickening controlled., This paper considers the development, plant implementation and application of X-ray diffraction (XRD) analysis and near infrared (NIR) analysis for reliable quantitative mineralogical ore profiling at several copper mines. This allows ore routing to be optimised, ore-type profiling improved, swelling clay identified so that permeability losses in heap leaching can be rectified, conveyor chute plugging prevented, flotation problems avoided and tailings thickening controlled.

In this program, four Chevrolet S-10 vehicles were tested for cold starting performance. The vehicles consisted of two gasoline-fueled control vehicles and two M85-fueled test vehicles. The M85 vehicles were converted to methanol use with the Bank of America conversion technology. Two engine geometries were tested. The 2.5-liter L-4 throttle body injected engine was used in one M85 and one control vehicle. The 2-8-liter V-6 carbureted engine was used in one M85 and one control vehicle. All vehicles were tested in a refrigerated trailer capable of maintaining temperatures of ambient to 0 F (-18 C). Both gasoline control vehicles were started successfully at temperatures of 0 F. Minimum starting temperature for the gasoline vehicles is lower than the 0 F temperature that the cold box was able to attain. The methanol vehicles were tested with M85 fuel, M82 fuel, SAE 40 lubricant, 10W-30 lubricant, and, in one case, with a block heater. The V-6 vehicle started much easier and a lower temperatures than the L-4 vehicle, believed to be due to the heated grid under the carburetor and the ability of the operator to control the initial mixture by using the accelerator pump. Useful minimum unaided starting temperatures for the V-6 vehicle was approximately 20 F (-7 C) and 45 F (7 C) for the L-4 using M85 and an SAE 40 lubricant. The use of M82 fuel lowers the starting temperatures by about 10 degrees for both vehicles. The tuning of the fuel injection system on the L-4 throttle body injected engine can vary the minimum starting temperatures widely. The L-4 vehicle was successfully started at temperatures lower than 0 F with the use of a block heater. (Author)

WADD gear machine was used to evaluate the gear load-carrying capacities of three high-hot-hardness gear materials, Cartech EX 00014, CBS 1000 M, and Vasco X-2 ESR, at 74 deg C and 218 deg C (165 deg F and 425 deg F). One MIL-L-23699C lubricant was used to evaluate all three gear materials at the two test temperature levels. Three additional military specification type turbine engine lubricants were included in the evaluation of the Vasco X-2 ESR gear material.

A description of an automated gas turbine engine simulator, designated the AFAPL engine simulator, and a discussion of the test results obtained from 31 tests using the simulator are presented. The No. 4-5 bearing compartment areas of a J57 turbine engine are used as the basic hardware for the simulator. The simulator is driven by a variable-speed drive system, throught the accessory drive gearbox, providing simulator mainshaft speeds up to 9,120 rmp. Electrical resistance heaters are used to heat the air surrounding the oil-wetted areas within the No. 4-5 bearing compartment areas. The temperatures, pressures, and rpm are controlled at prederermined levels and monitored throughout the 9120-6000 rpm speed cycling sequences and the soakback periods by a Hewlett-Packard mini-computer system, which is also programmed to draw 5-hr interval test-oil samples, control test-oil sump level, provide safety shut-off protection, as well as print out and plot test information generated during each individual test. Simulator results obtained on eight turbine engine lubricants, for which full-scale engine data are available, show a very good correlation of the deposit ratings obtained using the AFAPL engine simulator and the deposit ratings from full-scale engine tests.

A description of an automated gas turbine engine simulator, designated the AFAPL engine simulator, and a discussion of the test results obtained using the simulator are presented. The No. 4-5 bearing compartment areas of a J57 turbine engine are used as the basic hardware for the simulator. The simulator is driven by a variable-speed drive system, through the accessory drive gearbox, providing simulator mainshaft speeds up to 10,000 rpm. Electrical resistance heaters are used to heat the air surrounding the oil-wetted areas within the No. 4-5 bearing compartment areas. The temperatures, pressures, and rpm are automatically controlled at predetermined levels and monitored throughout the 9120-6000 rpm speed cycling sequences and the soakback periods by a Hewlett-Packard mini-computer system, which is also programmed to automatically draw 5-hr interval test-oil samples, control test-oil sump level, provide safety shut-off protection, as well as print out and plot test information generated during each individual test. Simulator results obtained on eight turbine engine lubricants, for which full-scale engine data are available, show a very good correlation of the deposit ratings obtained using the AFAPL engine simualtor and the deposit ratings from full-scale engine tests. (Author)

A rotating cylinder deposition test for the evaluation of aircraft turbine engine lubricants was investigated. The device was selected for study on the basis of its promise for achieving controlled or measurable lubricant films and oxidative exposure conditions. Evaluation tests with this configuration were performed with four coded lubricants. Performance criteria in these tests included deposit rating, viscosity and neutralization number change, and oxygen consumption. Test conditions selected for this series of runs resultes in severe fluid deterioration for all but one lubricant.

A description of a gas turbine engine simulator, designated the AFAPL engine simulator, and a discussion of the results obtained using the simulator are presented. The AFAPL engine simulator was designed to provide a flexible test facility with the capability of closely simulating the critical temperatures and oil flow variables experienced by the lubricant in the full-scale engine. The No. 4-5 bearing compartment areas of a J57 turbine engine are used as the basic section of the simulator. The simulator is driven by a 100-hp variable-speed drive system through the accessory drive gearbox, providing simulator mainshaft speeds up to 10,000 rpm. Electrical resistance heaters are used to heat the air surrounding the oil-wetted areas within the No. 4-5 bearing compartment areas to the controlled test temperatures.

Six bearings were endurance tested in pairs in a machine utilizing back-to-back loading of the bearing pairs. Each pair of bearings were run using a predetermined speed and load test schedule for 1,000 hours or failure, whichever occurred first. A description of the test program and the results obtained are described.

Ten SwRI rolling fatigue testers, using a 4-ball test specimen configuration, were employed to evaluate the effect of four different film thickness ratios on the rolling fatigue life of AISI 52100 CEVM steel balls. Two synthetic lubricants (one MIL-L-7808 and one MIL-L-23699) were used in the program at two test temperature conditions, 150F and 300F, thereby providing four different film thickness ratios ranging from 0.0972 to 0.6489. The results show no significant difference, at the 90-% confidence level, in the fatigue life for the CEVM 52100 steel balls using the two synthetic lubricants at constant test temperatures of 150F and 300F. However, when the results are compared on the basis of the film thickness ratio, it is seen that the two lubricants differ significantly in fatigue behavior at the 90% confidence level. This suggests that rolling fatigue life is dependent upon both the film thickness ratio and the lubricant type., See also AD-884 078.

The report contains a compilation of the individual test data sheets for all tests reported in AD-869 884. The data sheets are presented in the order of test number., See also Volume 1, AD-869 884.

The report describes test methods and procedures used in the study of the oxidation-corrosion-deposition (O-C-D) characteristics of aircraft turbine engine lubricants employing a glassware-type apparatus. Development and evaluation of a light meter device for quantitative measurement of glassware deposits are also discussed. An extensive experimental effort using eight MIL- L-7808-type lubricants is described. The study encompassed an investigation of the factors of time, temperature, moisture, and metal types in relation to lubricant breakdown in an oxidizing (air) atmosphere. A similar, less extensive program was conducted for four lubricants using an inert (nitrogen) atmosphere.

Oxidation-corrosion test data are presented for 46 lubricants, 40 MIL-L-7808 type lubricants and six MIL-L-23699 type lubricants, evaluated at one or more temperatures within the range of 350 to 400 F. In addition, the compatibility of selected lubricants when blended with lubricants of the same general class was evaluated. The test conditions which were varied were temperature and the use of reflux and nonreflux glassware configurations. Relatively milk oxidative degradation occurred at 350 and 375 F test conditions. Using an arbitrary rating point of 100% viscosity increase (100 F) as the maximum viscosity increase allowable for satisfactory performance, 23 of the 37 lubricants evaluated at 385 F were satisfactory using the nonreflux test procedure. Sixteen of the 29 lubricants evaluated at 390 F were satisfactory and only four of the 16 evaluated at 400 F provided satisfactory performance. The effect of condensate return at 385 F revealed that the majority of lubricants evaluated were unaffected.

A summary of the gear load-carrying capacity of Reference Oil C, determined by from six to eight cooperating laboratories using Ryder gear machines, WADD gear machines, and AFB gear machines, is presented. Based upon 916 determinations obtained during a 4-yr period using the three different machine types, the overall mean load-carrying capacity for Reference Oil C is shown to be 2957 lb/inch. A possible difference, at the 95 percent is confidence level, in the load-carrying capacity obtained using test gears with different gear letter prefixes is indicated. This possible difference in test gears, however, is overshadowed by the wide spread, 474 lb/in., in the mean load-carrying capacities obtained by the different laboratories. Inspection data for Reference Oil C, recorded semiannually for a period of 5 yr, does not indicate any significant change in viscosity, neutralization number, API gravity, saponification number, water content, trace sediment, or contamination. (Author)

The report summarizes the work done toward the development of suitable test methods for evaluating the compatibility of materials with liquid oxygen under impact. The work indicates that the potential explosive hazard of a material may be defined by two parameters: impact sensitivity and reaction intensity. Impact sensitivity is measured in terms of the drop height at which the material has a 50-percent probability of reaction. Reaction intensity is measured in terms of the maximum peak pressure of the air shock wave generated by the reaction. Detailed test methods for determining impact sensitivity and reaction intensity are proposed. It is recommended that tests be run on a wide variety of liquids, greases, and solids, in strict accordance with the proposed test methods, in order to establish their repeatability and reproducibility.

A detailed test method is presented for evaluating deposit and degradation characteristics of aircraft turbine engine lubricants at 350/500 F temperature conditions. Minor modifications to the equipment and test procedure allow tests to be performed at temperature levels up to 650/700 F. Deposit ratings obtained on 27 lubricants show the standard deviations of the individual mean deposit ratings to vary between 1.0 and 23.0, with 21 of the 27 values being less than 12.0. The overall standard deviation of the mean for all 27 values is shown to be 10.4. Analysis of the results shows that three or more tests are generally required, in order to obtain reasonable confidence in the mean deposit rating. (Author)

A continuing investigation of the deposition characteristics of synthetic ester-base lubricants, as typified by Military Specifications MIL-L-7808 and MIL-L-23699, led to the discovery of the presence of appreciable metal (iron) content in the deposits recovered from the conventional bearing depositon tests and full-scale engine tests. Accordingly, a special test method was utilized to study the effect of wear metal generation on deposit ratings. The concentration of iron in the test lubricant and in the principal deposits was monitored by atomic absorption spectroscopy. A direct indication of the extent of wear metal generation was provided by weight loss measurements of spring-loaded mild steel wear plates mounted within the test-lubricant sump. Significant deposit rating increases were found in many instances, dependent upon the test lubricant and mangitude of wear. It is concluded that a knowledge of the inherent wear process is imperative in any definitive study of lubricant depositon. (Author)

This program was concerned with the further development of the ABMA impact tester and the investigation of different test methods used to determine the impact sensitivity of materials in contact with rocket propellants. It was found that the specimen cup material and design had a significant effect on plummet rebound height. The use of a modified anvil region assembly, including a steel specimen cup, significantly increased the reactivity of materials subjected to impact in the presence of LOX in addition to improving plummet rebound height repeatability. The 'up-and-down' test procedure, from which a statistical estimate of the drop height producing a 50-percent probability of reaction may be obtained, was investigated. The results of 10 separate up-anddown tests on one grease material showed repeatability to be excellent. Results were also obtained for additional greases and these results showed that some greases rated as satisfactory had about the same 50-percent points as other greases considered unsatisfactory, with the only apparent difference being the intensity of the reactions. (Author)

Rolling-contact fatigue and were data were obtained for a diester, a SAE 20 paraffinic mineral oil, and a methyl chlorophenyl silicone, using a 3-ball/cone fatigue tester and 52100 air-melt tool steel test specimens. The test were conducted in dry filtered air at 10,000-rpm spindle speed, 200 F test temperature, and 700,000-psi initial maximum Hertz stress. It was found that the oil gave the shortest fatigue life and the highest wear rate, the mineral oil intermediate fatigue life and intermediate wear rate, and the silicone fluid the longest fatigue life and the lowest wear rate. The fatigue lives of the three lubricants were the same in relative order as the results of several other bench-type and full-scale tests.

Investigations were conducted to determine the possible effect of selected aircraft gas turbine engine lubricants and various solvents on the removal of carbonaceous deposits which had accumulated during service on the No. 2 bearing rear support of the J-57 engine. Six MIL-L-7808 type and one MIL-L-23699 type lubricants and six solvents were included in this program. Under the test procedures used, the deposits on the bearing support specimens were found to be quite stable in the presence of all seven lubricants investigated; no loosening or sloughing of the deposits was observed. Of the six solvents evaluated, only Cities Service 26 was found to be effective in removing significant amounts of deposits from the specimen. Flashing of liquid water, which had penetrated the deposit covered surface, loosened crinkled, blistered, and flaked deposits but had no effect on smooth carbon or varnish. (Author), Rept. on Bearing Support Deposits Program.