Document Y9wvNopMDVZDRvje656w220E

fcari&ey sSearCh Library SA LoatS__ / Monsanto Chemicals-Plastics V/i APR 1 W AROCLOR* A NONFLAMMABLE HYDRAULIC FLUID FOR DIE-CASTING SYSTEMS Monsanto Technical Bulletin No. P-137 May 1, 1950 (Supersedes March 28, 1949) Monsanto Chemical Company St. Louis 4, Mo. Aroclor 1248, chlorinated biphenyl, the safe and economical organic hydraulic fluid for metal die casting systems, eliminates the constant threat of serious fire hazard associated with the use of com bustible hydraulic fluids in the die-casting industry. ThiB safe and economical hydraulic fluid has been in continuous satisfactory use in individualized die-casting units for about ten years and in central ized systems for the past two years. * MOWS 01A29A v < I. INTRODUCTION Aroclor 1248, chlorinated biphenyl, the safe and economical organic hydraulic fluid for metal dle-castlng systems, eliminates the constant threat of serious fire hazard associated with the use of combustible hydraulic fluids In the dle-castlng Industry. There are not many available noncombustible organic fluids and only very few possess the over-all physical requirements of hydraulic fluids for dle-castlng systems. Notwithstanding the possibility of sustaining costly fire damage when using relatively Inexpensive petroleum oils, the economics Involved In replacing petroleum oils with the more expensive noncombustible organic hydraulic fluids Is an important factor to the industry. In this connection, It Is Important to emphasize that Aroclor 1240 appears to be substantially less expensive than the few other available noncombustible organic hydraulic fluids for this purpose. Aroclor 1248 has been used successfully In dle-castlng machines for many years and satisfactory continuous service records on Aroclor 1248 ex tend beyond ten years. It is used throughout the industry as widespread and leading dle-casters have Installed Aroclor 1248 to replace combus tible oils and also to replace other noncombustible organic fluids, because of the demonstrated good performance obtainable with Aroclor 1248 and because of Its lower initial cost and lower "make-up" require ments in the system. II. INDIVIDUALIZED DIE-CASTING SYSTEMS Aroclor 1248 has been used continuously for many years In Individualized dle-castlng units using machines built by Lester Engineering Company (13), The Hydraulic Press Mfg. Co. (11), H. L. Harvlil Mfg. Co. (9), and the Cleveland Automatic Machine Co. (4), as well as excellent ''home built" unite. Frequently, these machines are equipped with vane type centrifugal pumps such as the ones made by Vickers, Incorporated (21), but other types of centrifugals may also be used. The Watson-Stillman Company's (22) dle-castlng machines are used as Individualized units equipped with Ollgear piston type pumps made by The Ollgear Company (15). Aroclor 1248 Is suggested as a noncombustible hydraulic fluid for Installations of this type. In most Instances, the normal operating temperature of the hydraulic fluid Is within the range of 80-120F. and this temperature may or may not be controlled by Jacketed water coolers, depending on the spe cific design of the dle-castlng machine. Most of these machines use 60-200 gallons of the hydraulic fluid and operate at pressures ranging as high as 1,000-3,000 p.s.l. HONS 0 74295 2. III. CENTRALIZED DIE-CASTING SYSTEMS Aroclor 1248 has been In continuous satisfactory use for a number of years in centralized die-casting systems consisting of batteries of the machines connected to a central tank of the Aroclor hydraulic fluid. These systems are usually equipped with piston type pumps such as made by The Ollgear Company and have an aceumulater in the line to maintain smooth operation. Such centralized systems may operate with 2,000 gallons, or even more, of Aroclor 1248. Systems of this type using Aroclor 1248 and Ollgear pumps have been in continuous service for a number of years with apparently satisfactory performance. IV. PHYSICAL PROPERTIES OP AROCLOR 1248 The physical properties of Aroclor 1248 are listed below with similar constants for Aroclor 1254. The reason for including Aroclor 1254 is that in some Instances, especially for viscosity considerations, it may be desirable to blend small portions of Aroclor 1254 with Aroclor 1248. For more complete data about the low vapor pressure of Aroclors, their low vaporization rates, their viscosity ranges, their noncorrosive properties, high order of stability to heat and corrosive influences, as well as other pertinent qualities, please refer to Monsanto Techni cal Bulletin No. P-115 entitled, "The Aroclors" (14 bibliography reference). TABLE I. Outline of Physical Properties Aroclor 1248 Aroclor 1254 Porm Yellow tinted mobile oil Light yellow viscous oil Color--APHA Acidity--Maximum (mgm. KOH/Gm.) Average Coefficient of Expansion - cc/cc/C. 100 Max. 0.015 0.00070 (25-65C.) 100 Max. 0.015 0.00066 (25-65C.) Denslty-Speclflc Gravity 25/25C. (77"/77*F.) Pounds per Gallon 25"C. (77F.) 1.447 to 1.457 12.08 1.538 to 1.548 12.83 MOhS 3- TABLE I. (continued) Aroclor 1248 Aroclor 1254 Distillation Range--ASTM D-20 (Mod.) Corr. C. . Vaporization Rate gms/cm2hr/100C. Flash Polnt--Cleveland Open Cup C. F. 340-375 0.000152 193-196 379-384 365-390 0.000053 None Fire Paint--Cleveland Open Cup C. Pour Point--ASTM D-97 C . F. None -7 19.4 None 10 50 Viscosity--Saybolt Universal Sec. (ASTM D-88) 210 F. (98.9 C.) 130F. (54.4C.) 100F. (37.8C.) 36-37 69-78 185-240 44-48 260-340 1800-2500 Absolute Viscosity--Centlpolses 212 F. (100C.) 122F. ( 50C.) 77F. ( 25C.) 4.2 25 208 8.5 146 777 V. NONCOMBUSTIBLE QUALITIES OF AROCLOR 1248 FLASH POINT. Limitations of this test for the prediction of the fire hazard of relatively nonvolatile organic fluids have been recognized by the ASTM committee (1). FIRE POINT is a more significant measurement. The National Board of Fire Underwriters Laboratories (20) concur that fire tests more truly reflect the (lack of) fire hazard of Aroclor. SPONTANEOUS IGNITION TEMPERATURE. The combustion resisting qualities of Aroclor 1248 are indicated by its high spontaneous ignition tempera ture of 704C. (1,299F.) determined by Sullivan, Wolfe and Zlsman (19), using the convenient apparatus described by Sortman, Beatty and Heron (18). Under industrial use conditions the spontaneous ignition temperature will be determined by factors including the nature of the hot surface, the amount of liquid impinging on it, the volume of enclosed space, and the ventilation. In this connection, we wish to refer to an HONS 074297 K ( observation concerning the use of Aroclor 1248 as a noncombustible heattransfer medium In Aroclor heating systems. An accidental failure In one of our Aroclor heating Bystems demonstrated the nonflammability of Aroclor 1248 and its freedom from the hazard of fire propagation. An operator'8 failure to start the circulation of the heat-transfer medium when the gas heater was on resulted In excessive coll tempera tures, causing the lower coll (steel) to soften and sag Into the fire chamber. A weld ruptured and Aroclor 1248 poured Into the red hot fire chamber in contact with the flame. Smoke arose from the heater but there was no Internal fire. After the gas flame was cut off. the smok ing stopped. SPRAY FLAMMABILITY. When a line ruptures In a dle-casting system where the hydraulic fluid Is under relatively high pressure, a spray or mist prevails. The possible fire hazard of Aroclor 1248 under these con ditions requires considerations not covered by the foregoing discussions relative to the material In the liquid form. In their comprehensive study, "Flammability of Higher Bolling Liquids and Their Mists", Sullivan, Wolfe and Zlsman determined the spray flammability limit of numerous materials In accordance with the percentage of oxygen required for com bustion. This value was then correlated with the results of incendiary firing tests of the fluid conducted at the Naval Proving Ground, Dahlgren, Virginia. The per cent oxygen requirement for Aroclor 1248 combustion In the spray flammability limit studies was established at 64#. It was observed that fluids requiring over 45-50# of oxygen in the spray test failed to cause a fire in the Incendiary test. These results firmly establish the nonflammable and noncombustible qualities of Aroclor 1248. Moreover, these results on spray flammability studies seem most pertinent since they reflect conditions prevailing In the case of pressurized systems such as used in metal dle-casting. There fore, we are taking the liberty of presenting the data In the following Table II as taken from the publication by Sullivan, Wolfe and Zlsman to compare this highly significant spray flammability rating given to selected chlorinated hydrocarbons, organic phosphates, etc. Benzene and a petroleum oil are Included for comparison purposes. 5. r Fluid TABLE II. Flammability of Certain Higher Bolling Liquids and Their MlBts Spray ViBeosity Flash Pt. Cs. at (COC) (1) 100F. F. Fire Pt. (COC) (1) "F. Flammability S .1 .T.(2) Limit % F. Oxvaen Naval Ordnance hydraulic oil O.S. 1113 Benzene Chlorobenzene o-Dlchlorobenzene 1, 2,4-Trichlorobenzene Trlchlorddlphenyl (Aroclor 1242) 41.8 0.58 0.5? 0.84 1.1 17.7 315 12 90 165 260 350 340 - None 633 505 1295 >1000 1230 14 12 14 29 44 45 AROCLOR 1248 (Tetrachlorodlphenyl) Diphenyl ether Chlorodlphenyl ether Dlchlorodlphenyl ether Tr1ch1orod1phenyl ether Trimethyl phosphate Trlbutyl phosphate Trioctyl phosphate Tricresyl phosphate Hexamethy1 tetra- phosphate Tetrabutyl pyro phosphate Dioctylphenyl phosphonate Diphenyl mono (p-tert- butyl phenyl) phos phate Dl-(o-ehlorophenyl) monophenyl phosphate 45.4 2.6 3.0 5.9 8.7 - 2.6 8.1 29 38-3 8.9 11.5 40.3 34.3 380 265 260 300 325 225 285 380 500 >510 465 435 465 510 None 275 335 465 4901 245 370 465 685 None 720 480 720 >760 1300 _ 903 - 680 1170 920 845 630 1076 1296 64 11 27 33 42 47 27 13 19 31 14 21 12 21 (1) Cleveland Open Cup (2) Spontaneous Ignition temperature In light of the Importance of spray flammability as demonstrated to be the most significant determination of the noncombustible qualities of higher boiling fluids and their mists, It Is indeed interesting to note the lack of correlation between this value and other constants, such as HONS 07*2" 6. flash point, fire point and especially the spontaneous ignition tempera ture. VI. RESISTANCE OF STRUCTURAL MATERIALS TO AROCLOR 1248 The noncorrosive qualities of Aroclor 1248 and the strong resistance of structural materials to Aroclor 1248 are highly important factors in the practical uBe of Aroclor as a hydraulic medium in die-casting sys tems. The following Table III indicates the resistance of structural materials to Aroclors 1248 and 1254. TABLE III. Resistance of Structural Materials To Aroclors 1248 and 125? Metals 1248 25C . ,ilg5"c . 1254 n2a5rC. 125 s' Aluminum Copper Magnesium Nickel Silver Tin Zinc Mild Steel Phosphor Bronze Red Brass Stainless Steel Yellow Brass RRRR R DRD RR R R R HR R R RR RRRR RRRR R RRR RR R RR RR R DPR D DR D RR RR RR RR R Re R De RR--Excellent resistance- -less' than 1.0 x 10^ cm/day penetration 0.00014 ln/yr. ,, R -- Good reslstance--has penetration between 1.0 x 10 and 10 a 10 cm/day or between 0.00014 and 0.0014 ln/yr. . D --Doubtful resistance--has penetration between 10 x 10" cm/day and 100 x 10 cm/day or between 0.0014 and 0.014 in/yr. e --Following the letter indicating resistance signifies material may be better than indicated if totally immersed since weight loss is believed to come from oxidation of the part of test strip exposed to air. HONS C743Q0 I( VII. PACKING MATERIALS AND GASKETS SUITABLE FOR USE WITH AROCLOR 1248 IN DIE-CASTING SYSTEMS Results of accelerated laboratory tests show that Hycar P., Koroseal, Perbunan, Neoprene and various other "rubbers" are softened by Arcclors, especially at elevated temperatures. Accordingly, questions arise about the use of these materials for gaskets on dle-casting machines using Aroclor. However, from practical experience In the operation of die-castlng machines, It has been noted that fittings, such as the ball Joints made by Chlksan Tool Company (3), containing a small Neoprene gasket have given very good service under long continuous use when Installed In die-casting systems operated with Aroclor. Also, Neoprene lined, metalized flexible tubes used on the return lines of the dlecasting -machines appear to give good service with Aroclor. In some instances it appears almost necessary to use flexible tubes, especially on the return lines of the dle-casting machines. If possible to do so. It would seem desirable to use rigid lines fitted with ball Joints such as made by Chlksan or Barco Swivel Joints (2). For pipe connection, welded Joints are not necessary but in the case of welded flange connections, these may be satisfactorily gasketed by the use of a thin sheet of aluminum. Various packing materials suitable for use with Aroclor at elevated temperatures include Garlock Packing Company's (8) #7021, 1/8 Inch aBbestos fiber sheet for flange connec tions. Garlock'b #117 braided packing Is used in valves and Garlock #234 packing is used for pumps; also, Garlock #431 and Chevron 7050-C materials are suitable packings. Likewise, Durametalllc (6) spiral asbestos fiber may be used. Doubtless, Johns-Manville Corp. (12) and others have comparable packing materials which would be suitable. In all instances, when ordering packing, it should be indicated to the supplier that the material is intended for use with Aroclor 1248. Teflon, duPont's (7) polytetrafluroethylene, is not attacked by hot Aroclor (130C.) and is to be recommended as a gasket material. Thlokol is not attacked by Aroclors at ordinary temperatures and especially Thlokol I605-A appears of interest for use with Aroclors in die-castlng systems. The maximum temperature ranges at which Thlokol is suitable are indicated as follows: Thlokol Type A - 130-200F. max. Thlokol Type FA - 150-200F. max. Thlokol Type ST - 250-300F. max. Dow Coming's (5) Silastic, Silicone 180 is very resistant to hot Aroclor and use of this material is suggested. The changes in proper ties of Silicone 180 when immersed in hot Aroclor for 70 hours at 150'C. are summarized as follows: MGNS 074301 === 8. 1. Lowering of the hardness by about 20 points. 2. Improvement In the elasticity by several points. 3. Practically no change In tensile strength 4. An appreciable Increase in the ultimate elongation. Other types of packing materials recommended by the manufacturer for use In Aroclor installations include the following Palmetto (16) pack ings: Hydraulic Service (Normal Temperatures) Hod packing U Ring packing Flange packing Kup packing Sheet packing & gaskets - Palmetto Pyramid Packing #2510 - Palmetto U Ring Packing #2610 - Palmetto Flange Packing #2810` - Palmetto Kup Packing #2710 - Palmetto Hl-4 Sheet Packing #2910 Heat-Transfer Service Rod packing - Palmetto High Pressure Packing #2200 Sheet packing & gaskets - Palmetto Hi-4 Sheet Packing #2910 With reference to the manufacturer and also the user of die-casting equipment, it is highly advantageous if the same packing materials generally used with oil can be used also with Aroclor 1248. In this connection, in the case of the Ollgear Company hydraulic equipment, it Is noted that such packings as Thiokol, which is used for gaskets, and Oarlock #431, which is used as ram packings on most Ollgear equip ment, can be used either with oil or with Aroclor 1248. Vickers, Incorporated advise that all packing materials will have to be other than those normally used for petroleum base fluids to prevent rapid deterioration, and these are available through Vickers, Incorporated for their own equipment, or many of the suppliers of standard sealing elements. VIII. LUBRICATION Aroclor 1248 has lubricating properties and is used in die-casting systems most frequently without the addition of added lubricants. However, in the case of piston type pumps where high lubricity Is a requirement, sometimes the practice is to add not more than 5% of a high lubricity oil to the Aroclor. Oils of this type In use are DTE medium heavy high lubricity oil and Pennsylvania Refining Company's (17) #90 VI light stock oil. Other similar oils are available for this purpose. MONS 074302 Q. r Aroclor 1248 Is recognized in the Industry as an EP lubricant and its heavy load carrying quality without seizure Is reflected by tests made with a hydraulic fluid containing a substantial proportion of Aroclor. The data pertains to results with an Almen test machine. During the standard test, the hydraulic fluid carried the full 30-pound load nor mally used as maximum on the Almen test. The torque at maximum load passed, average of 2 runs, was found to be 28.5 for the hydraulic fluid built on Aroclor as compared with a value of 14.0 for SAE 10 motor oil. IX. VISCOSITY The viscosity of Aroclor 1248 seems to be within the range required in the normal operation of many industrial pumps and hydraulic equipment. As previously indicated, the viscosity of Aroclor 1248 can be increased by the addition of Aroclor 1254. In light of the influence of tempera ture on the viscosity of Aroclor, this factor should be given considera tion with reference to the operation of the pumps or hydraulic system in which Aroclor is used. As a general indication of the viscosity requirements for different types of pumps, Vickers, Incorporated specifies the following for use with its pumps: Industrial Machinery Installations (Ambient Temperature 50"F. to 90"F.) Type of Installation Oil Viscosity Vane Type Pumps Machine tools operating at pressures up to 1000 p.s.i. 150-225 S.S.U. @ 100F. Presses and other heavy machinery 2T5-315 S.S.U. @ 100F. Piston Type Pumps All industrial machinery 275-315 S.S.U. i @ 100F. Piston Type and Oear Type Fluid Motors All industrial machinery 150-315 S.S.U. @ 100F. Vickers recommends that the oil temperatures in the hydraulic circuit should be maintained between 60' and 130*F. If, for reasons of non operation for extended periods, the temperature drops below 60F., the fluid should be warmed to that temperature before starting operations. HONS 07003 10. Coolers should be provided to prevent temperatures In excess of 130'F., which will comply with the temperatures demanded by the Joint Industry Conference Hydraulic Standards, and.should also avoid the necessity of having to use vent ducts from any open or serol-open reservoir. Referring to the fact that the specific gravity of Aroclor 1248 is greater than the similar value of average petroleum base fluids used. Inlet conditions to pumps should be carefully scrutinized to Insure the absence of cavitation. X. FILTRATION It seems prudent to maintain clean oil regardless of the specific hydraulic fluid used In die-castlng systems. Small particles of dirt metal chips and sand from the castings seem to work their way into the hydraulic fluid whether the Installation Is a new one or one that has been in service for many years. Aroclor 1248 has a tendency to suspend such impurities. Although It Is not always practiced, nevertheless. It seems Important to provide adequate filtration so that abrasive particles are removed from the system and the Aroclor 1248 is kept clean. Many die-castlng machines are equipped with Internal fine mesh wire screens. These filters are suitable for removing the larger particles but to keep the Aroclor in a satisfactory clean condition, the recom mendation Is to filter the Aroclor through a bed of suitably processed granular Fuller's earth. There are available a number of satisfactory filtering mechanisms or oil purifiers which may be used continuously or Intermittently. Probably one of these filters available as a con venient portable model would be the most economical as It could be used to clean the oil In a number of dle-casting machines. As one example of a supplier of such equipment, we wish to refer to the Honan-Crane Corporation (10). XI. DERMATOLOGY AND TOXICOLOGY Reeulte of standard skin patch tests using over 100 Individuals show that Aroclor 1254 Is neither a skin irritant nor a skin sensitizer (14). We would expect that these results would serve to indicate that Aroclor 1248, which Is only slightly lower In chlorine content than Aroclor 1254, 1b also neither a skin Irritant nor a skin sensitizer. Although the vapor pressure of Aroclor 1248 Is quite low and for all practical purposes the material Is nonvolatile, nevertheless, when Aroelors are heated to elevated temperatures, vapors arise and these vapors bear a degree of toxicity and should not be breathed. This SONS C74304 consideration Is, of course, minimized in the case of using Aroelor 1248 in die-caating systems, which are necessarily thoroughly enclosed to prevent even the smallest kind of a leak, and the operating tempera ture is relatively low since practical operation never exceeds about 140*F. Aroelor 1248 has been used for over ten years in individualized and centralized die-casting systems with complete freedom from any trouble or fear of any toxic effects. If Aroelor 1248 comes in contact with the worker's skin, the skin should be washed in an ordinary manner with soap and water. If the Aroelor is sufficiently hot so as to cause a burn when in contact with the skin, the burn should be treated in the same manner as any ordinary burn. Aroelor adhering to the burned area need not be removed immediately unless treatment of the burn demands It, in which case soap and water or repeated washings with a vegetable oil is recommended. MONSANTO CHEMICAL COMPANY St. Louis 4, Mo. New York-Chicago-Boston-Birmlngham-Charlotte-Cincinnati-Cleveland Detrolt-Philadelphia-Los Angeles-San Pranclsco-Montreal PQBtag M-550 Rev. Printed in U.S.A. HONS 074305 BIBLIOGRAPHY (1) Am. Soe. Testing Materials, Proc. Am. Soc. Testing Materials, 34, 53 (1934). (2) Barco Manufacturing Co., 1301-15 Winnemac Ave., Chicago, Illinois. (3) Chlksan Tool Company, Brea, California. (4) Cleveland Automatic Machine Co., 4900 Beech Street, Cincinnati 12, Ohio. (5) Dow Corning Corp., 592 Saginaw Road, Midland, Michigan. (6) Durametalllc Corp., 1936 Hall Street, Kalamazoo 24-F, Michigan. (7) ' E. I. duPont de Nemours tc Co., Inc., Wilmington 98, Delaware. (8) Oarlock Packing Company, 250 Main Street, Palmyra, New York. (9) H. L. Harvill Mfg. Co., Harvill Building, Corona, California. (10) Honan-Crane Corporation, Lebanon, Indiana. (11) The Hydraulic Press Mfg. Co., 83O Marion Road, Mount Gilead, Ohio. (12) Johns-Manville, 22 East 4oth Street, New York 16, New York. (13) Lester Engineering Co., 2711 Church Street, Cleveland 13. Ohio. (14) Monsanto Chemical Co. Technical Bulletin No. P-115, "The Aroclors. (15) The Oilgear Company, 1560 W. Pierce St., Milwaukee 4, Wisconsin. (16) Palmetto Packings made by Greene. Tweed & Co., N. Wales, Penna. (17) Pennsylvania Refining Company, 2686 Lisbon Ave., Cleveland, Ohio. (18) Sortman, C., Beatty, H., and Heron, S., Ind. Eng. Chem., 33, 357 (1941) . (19) Sullivan, M. V., Wolfe, J. K., and Zisman, W. A., Ind. Eng. Chem., 39, 1607 (1947). (20) Underwriters' Laboratories, "Miscellaneous Hazards No. 2498", Chicago, Illinois, 1934. (21) Vickers, Incorporated, 1402 Oakman Blvd., Detroit 32, Michigan. (22) The Watson-Stillman Co., 109 Aldene Road, Roselle, New Jersey. MOWS 074306 13. 4, ) / Monsanto Chenucals-Plastics __ k^L_ MQNS 07A3Q7