- Email: [email protected]
28. Evaluation of vehicle corrosion preventives
74
ABSTRACTS shunt transmission--gearing assisted by hydrostatics--is the most promising development for automotive application. [M.I.R.A.]
24.
Lyeon, D. L. Engineering challenges of lunar exploration. Civil Engineering. ASCE, December 1965, pp. 40-43. The U.S. expects to put astronauts on the moon in this d e c a d e - - t o really explore it. Plans made for NASA, with the cooperation of the Corps of Engineers, U.S. Army, visualize a n u m b e r of individual modules sent singly to the m o o n and joined into a unified complex. The first three-man unit would have m i n i m u m systems and mobility for a three-month stay. The most advanced base would provide shelter, equipment, and mobility for 18 men for two years or longer. The cost of personnel o n the moon is estimated at $60,000 to $100,000 per man-hour. Everything must be light, compact and efficient--and automated as far as practicable. The design, engineering development and construction of lunar facilities will require an intense investigational program on materials, equipment, systems and man's capabilities, and long lead times. This research will have many applications for engineered construction on earth, such as optimum man-machine relationships, improved power and power transmission devices, and closed ecological systems. [Author's Summary.]
25.
Mathews, G . P. Brake capacity--what, why, how? S.A.E. Paper, Farm, Construction, and Industr. Machinery Meeting, September 13-16 1965, p. 6. The paper describes the fundamental variables of brake-system operation. It explains what brake capacity is. how much of it is needed, and h o w it can be provided. The crucial problem in determining the required brake capacity is that it depends not only on vehicle data. such as weight. load, speed, and acceleration ability, but also on vehicle service. Therefore. two identical vehicles may need very different brake capacities. [M.I.R.A.]
26.
Moreno, E. F. and Domes, E. A. A unique concept in off-highway trucks. S.A.E. Paper, Earthmoving Industr. Conf., April 6-7 1965, p. 13. From reports on performance in service of the International 180 Payhauler, a 45-ton dump truck first produced in 1956, a "concept study" of the vehicle has been developed whose objective is to arrive at a combination of function and form which results in increased productivity and operating economy. The paper discusses in detail the various factors affecting productivity, including payload size, h . p . / t o n vehicle weight, payload/weight ratio, tyres, body weight/yard capacity, turning circle, manoeuvrability limits, suspension and stability, tractive effort. frame design, dumping efficiency, body and chassis form, and ability to operate as a tractive unit, [M.I.R.A.]
27.
Morgenstern, N. R. and Price, V. E. The analysis of the stability of general slip surfaces. Geotech., London, 15, 1, 79-93, March 1965. Equations of equilibrium, for vertical slice of potential sliding mass of any possible shape, with C o u l o m b - M o h r failure equation. eliminating normal pressure on sliding surface, can be reduced to two differential equations. These equations involve, besides stability factor F, three unknown functions, namely vertical shear force X and lateral effective thrust E" with its position 3'. T o make problem statically determinate, it was found convenient to express ratio of total thrust E and shear force X proportional to function /(x), which can be reasonably predicted from approximate theoretical stress distribution or field observation of stresses in dams, and to make the remaining unknown proportional to a factor h. Factors F and • may be found starting from arbitrary initial values, by systematic iterative computations programmed for electronic computer. In analysis of circular slip surface, comparison with Bishop's method showed close agreement. In same case, as well as in cases of noncircular slip surfaces in homogeneous section and typical earth d a m section, each solved for three assumed stress functions, it was found factor of safety was not very sensitive to stress distribution. Consequently this basically intricate method of analysis may be found very useful if soil conditions determine possibility of noncircular failures. [Applied Mechanics Review.]
28.
Mullley, H. C. Evalution of vehicle corrosion preventives. A.S.L.E. Preprint, No. 65AM 4B4, Annual Meeting, May 4-7 1965, p. 7. Vehicle corrosion, which is usually induced by the presence of moisture and an excess of oxygen, proves costly to vehicle owners. Much corrosion is due to improper application of the primers, undercoatings and paints intended to provide protection. Corrosion is accelerated by salt used for de-icing roads, and in some areas an admixture of calcium chloride, which is more corrosive than sodium chloride, is being employed. Manufacturers often attempt to combat corrosion
ABSTRACTS
75
by using zinc-enriched primers, galvanized steel, rust-proof body-drips, etc. Frequent washing of vehicles to remove salt may be harmful, as washed vehicles standing overnight in heated garages are exposed to ideal conditions for corrosion. Another attempt to prevent corrosion is by undercoating. This may merely deaden sound and vibration and prove ineffective as a corrosion-preventive because of, e.g. cracking or peeling of the undercoating, whereby corrosion spreads undetected between metal and coating, improper application, or careless preparation of the vehicle prior to undercoating. In recent years, many coatings which will effectively retard or eliminate corrosion have been marketed. The author's laboratory has evaluated these by laboratory and field tests so as to define the requirements of a suitable corrosion-preventive. Thirty-one products representing various compounds including grease, petrolatum, modified asphaltic, emulsion, resin phosphate, wax and neoprene type materials were classified into 8 groups. Tabulated test results of the materials as received in the container show that: (1) solid material varies from 35 per cent to 82 per cent of the compound as indicated by the volatility test; (2) the product can be formulated to have flash and fire-point values above 100°F to satisfy government safety requirements; (3) viscosity values are related to percentage of solvent and type of base metal used and are specially significant as regards sprayability; (4) the material itself has no apparent corrosive effect. Results are also given for tests of the materials as applied to metals. These evaluated low-temperature flexibility, protective quality against salt-spray, ability to creep between metal plates riveted together, etc. Field tests were carried out with various types of vehicles and compounds and in different areas. The procedures for applying the compounds, the parts of the vehicles treated, and the inspection procedures are described. Tables list values of the compounds as regards fire-resistance, low-temperature flexibility, high-temperature flow, salt-spray, acid and alkali resistance, and ability to provide creep and rust-removal, and adequate uniform coverage when applied by airless spray equipment. The compounds showed varying degrees of abrasion resistance on the underside of the vehicles processed. Periodic reapplication of coatings in such areas could form part of routine maintenance. Investigations have thus shown that several types of product can successfully prevent corrosion. Lists are given of the requirements which should be satisfied in tests of the materials as received and applied, and of the test methods which should be used. Corrosion-preventive product, application equipment and application procedure have been studied sufficiently to be integrated into an acceptable procedure for processing and maintaining vehicles of all types. [M.I.R.A.] 29.
Niemoeller, A, F. Radiation impedance of a piston on cohesive soil. J. Acoust. Soc. Amer. 37, 5, 879-894, May 1965. A method for determining the impedance (using radiation methods) of a piston on cohesive soils is discussed together with results showing the compliance presented to a circular piston on the surface of the clay soil. The experimental procedure shows the technique and details the procedure. The method of presentation of results in terms of mechanical impedance and frequency in cycles per second may be meaningful to others not necessarily accustomed to general soil mechanics terminology, but could be more useful if broken down and re-interpreted in terms of penetration resistance and frequency of cycles per second. The compliance technique showing the relationship between compliance in centimeters per dyne and both moisture and dry density is a useful form and does present to the reader an overall picture of the effectiveness of the method of determination of radiation impedance. The several limitations for the use of the purpose of compliance discussed by the author bears some exmination. Firstly, the assumption of a second-order dependence of compliance on density and moisture has not been shown to be valid experimentally. Secondly, and more important, the tests conducted from one soil have not been verified by checks on other types of soils. Thirdly, the influence of soil structure, remoulding, saturation, etc., has not been investigated and remains to be studied. The technique is useful in that it provides measurements of the force and velocity of the piston used for the determination of the real and imaginary parts of radiation and impedance as a function of excitation frequency of the piston. In the frequency range of 50 to 200 cycles per second the results show that the load presented to the piston by the soil becomes essentially the same as would be presented by a mechanical compliance, with dependence upon both moisture and the dry density of the soil. [Applied Mechanics Review.]
30.
Nouviare, J. Study of traflicability on cohesive soils, lngs Auto., 1964, 37 (8-9), 431--6. (In French, with French, English, Spanish, German and Italian summaries.) An illustrated
ABSTRACTS shunt transmission--gearing assisted by hydrostatics--is the most promising development for automotive application. [M.I.R.A.]
24.
Lyeon, D. L. Engineering challenges of lunar exploration. Civil Engineering. ASCE, December 1965, pp. 40-43. The U.S. expects to put astronauts on the moon in this d e c a d e - - t o really explore it. Plans made for NASA, with the cooperation of the Corps of Engineers, U.S. Army, visualize a n u m b e r of individual modules sent singly to the m o o n and joined into a unified complex. The first three-man unit would have m i n i m u m systems and mobility for a three-month stay. The most advanced base would provide shelter, equipment, and mobility for 18 men for two years or longer. The cost of personnel o n the moon is estimated at $60,000 to $100,000 per man-hour. Everything must be light, compact and efficient--and automated as far as practicable. The design, engineering development and construction of lunar facilities will require an intense investigational program on materials, equipment, systems and man's capabilities, and long lead times. This research will have many applications for engineered construction on earth, such as optimum man-machine relationships, improved power and power transmission devices, and closed ecological systems. [Author's Summary.]
25.
Mathews, G . P. Brake capacity--what, why, how? S.A.E. Paper, Farm, Construction, and Industr. Machinery Meeting, September 13-16 1965, p. 6. The paper describes the fundamental variables of brake-system operation. It explains what brake capacity is. how much of it is needed, and h o w it can be provided. The crucial problem in determining the required brake capacity is that it depends not only on vehicle data. such as weight. load, speed, and acceleration ability, but also on vehicle service. Therefore. two identical vehicles may need very different brake capacities. [M.I.R.A.]
26.
Moreno, E. F. and Domes, E. A. A unique concept in off-highway trucks. S.A.E. Paper, Earthmoving Industr. Conf., April 6-7 1965, p. 13. From reports on performance in service of the International 180 Payhauler, a 45-ton dump truck first produced in 1956, a "concept study" of the vehicle has been developed whose objective is to arrive at a combination of function and form which results in increased productivity and operating economy. The paper discusses in detail the various factors affecting productivity, including payload size, h . p . / t o n vehicle weight, payload/weight ratio, tyres, body weight/yard capacity, turning circle, manoeuvrability limits, suspension and stability, tractive effort. frame design, dumping efficiency, body and chassis form, and ability to operate as a tractive unit, [M.I.R.A.]
27.
Morgenstern, N. R. and Price, V. E. The analysis of the stability of general slip surfaces. Geotech., London, 15, 1, 79-93, March 1965. Equations of equilibrium, for vertical slice of potential sliding mass of any possible shape, with C o u l o m b - M o h r failure equation. eliminating normal pressure on sliding surface, can be reduced to two differential equations. These equations involve, besides stability factor F, three unknown functions, namely vertical shear force X and lateral effective thrust E" with its position 3'. T o make problem statically determinate, it was found convenient to express ratio of total thrust E and shear force X proportional to function /(x), which can be reasonably predicted from approximate theoretical stress distribution or field observation of stresses in dams, and to make the remaining unknown proportional to a factor h. Factors F and • may be found starting from arbitrary initial values, by systematic iterative computations programmed for electronic computer. In analysis of circular slip surface, comparison with Bishop's method showed close agreement. In same case, as well as in cases of noncircular slip surfaces in homogeneous section and typical earth d a m section, each solved for three assumed stress functions, it was found factor of safety was not very sensitive to stress distribution. Consequently this basically intricate method of analysis may be found very useful if soil conditions determine possibility of noncircular failures. [Applied Mechanics Review.]
28.
Mullley, H. C. Evalution of vehicle corrosion preventives. A.S.L.E. Preprint, No. 65AM 4B4, Annual Meeting, May 4-7 1965, p. 7. Vehicle corrosion, which is usually induced by the presence of moisture and an excess of oxygen, proves costly to vehicle owners. Much corrosion is due to improper application of the primers, undercoatings and paints intended to provide protection. Corrosion is accelerated by salt used for de-icing roads, and in some areas an admixture of calcium chloride, which is more corrosive than sodium chloride, is being employed. Manufacturers often attempt to combat corrosion
ABSTRACTS
75
by using zinc-enriched primers, galvanized steel, rust-proof body-drips, etc. Frequent washing of vehicles to remove salt may be harmful, as washed vehicles standing overnight in heated garages are exposed to ideal conditions for corrosion. Another attempt to prevent corrosion is by undercoating. This may merely deaden sound and vibration and prove ineffective as a corrosion-preventive because of, e.g. cracking or peeling of the undercoating, whereby corrosion spreads undetected between metal and coating, improper application, or careless preparation of the vehicle prior to undercoating. In recent years, many coatings which will effectively retard or eliminate corrosion have been marketed. The author's laboratory has evaluated these by laboratory and field tests so as to define the requirements of a suitable corrosion-preventive. Thirty-one products representing various compounds including grease, petrolatum, modified asphaltic, emulsion, resin phosphate, wax and neoprene type materials were classified into 8 groups. Tabulated test results of the materials as received in the container show that: (1) solid material varies from 35 per cent to 82 per cent of the compound as indicated by the volatility test; (2) the product can be formulated to have flash and fire-point values above 100°F to satisfy government safety requirements; (3) viscosity values are related to percentage of solvent and type of base metal used and are specially significant as regards sprayability; (4) the material itself has no apparent corrosive effect. Results are also given for tests of the materials as applied to metals. These evaluated low-temperature flexibility, protective quality against salt-spray, ability to creep between metal plates riveted together, etc. Field tests were carried out with various types of vehicles and compounds and in different areas. The procedures for applying the compounds, the parts of the vehicles treated, and the inspection procedures are described. Tables list values of the compounds as regards fire-resistance, low-temperature flexibility, high-temperature flow, salt-spray, acid and alkali resistance, and ability to provide creep and rust-removal, and adequate uniform coverage when applied by airless spray equipment. The compounds showed varying degrees of abrasion resistance on the underside of the vehicles processed. Periodic reapplication of coatings in such areas could form part of routine maintenance. Investigations have thus shown that several types of product can successfully prevent corrosion. Lists are given of the requirements which should be satisfied in tests of the materials as received and applied, and of the test methods which should be used. Corrosion-preventive product, application equipment and application procedure have been studied sufficiently to be integrated into an acceptable procedure for processing and maintaining vehicles of all types. [M.I.R.A.] 29.
Niemoeller, A, F. Radiation impedance of a piston on cohesive soil. J. Acoust. Soc. Amer. 37, 5, 879-894, May 1965. A method for determining the impedance (using radiation methods) of a piston on cohesive soils is discussed together with results showing the compliance presented to a circular piston on the surface of the clay soil. The experimental procedure shows the technique and details the procedure. The method of presentation of results in terms of mechanical impedance and frequency in cycles per second may be meaningful to others not necessarily accustomed to general soil mechanics terminology, but could be more useful if broken down and re-interpreted in terms of penetration resistance and frequency of cycles per second. The compliance technique showing the relationship between compliance in centimeters per dyne and both moisture and dry density is a useful form and does present to the reader an overall picture of the effectiveness of the method of determination of radiation impedance. The several limitations for the use of the purpose of compliance discussed by the author bears some exmination. Firstly, the assumption of a second-order dependence of compliance on density and moisture has not been shown to be valid experimentally. Secondly, and more important, the tests conducted from one soil have not been verified by checks on other types of soils. Thirdly, the influence of soil structure, remoulding, saturation, etc., has not been investigated and remains to be studied. The technique is useful in that it provides measurements of the force and velocity of the piston used for the determination of the real and imaginary parts of radiation and impedance as a function of excitation frequency of the piston. In the frequency range of 50 to 200 cycles per second the results show that the load presented to the piston by the soil becomes essentially the same as would be presented by a mechanical compliance, with dependence upon both moisture and the dry density of the soil. [Applied Mechanics Review.]
30.
Nouviare, J. Study of traflicability on cohesive soils, lngs Auto., 1964, 37 (8-9), 431--6. (In French, with French, English, Spanish, German and Italian summaries.) An illustrated