Document zo81gZrdk4XMG9371gvK6Obm

INTER-OFFICE MEMO TENNECO CHEMICALS, INC To E. V. Schenke at Burlington From I. A. Rumberg at Burlington Subject DEI-603-604 DOUBLE MECHANICAL SEALS BURLINGTON/FLEMINGTON Date April 4, 1977 Copy to W. Fogelsanger N. Quist > J. Sandstedt P. Scarito J. Sweeney C. Thompson Herewith attached Is the Design Study and Test Results of our Double Mechanical Seal Program to meet EPA requirements. lAR/ib Attachments COLORITE 018301 ENGINEERING DESIGN STUDY The Design Study was done by means of a 5 step investigation. 1) Establish what pumps are presently installed on VCM service. 2) Research the original specifications and data sheets of the existing VCM service piimps. 3) Evaluate the feasibility of installing double mechanical seals on our VCM service pumps. 4) If the above is concluded as a viable solution to our problem, then prepare a preliminary project scope and estimate, for installation of double mechanical seals on VCM service pumps. 5) Begin a test program to evaluate the best manufactured seal for our use. COLORITE 018302 COLORITE 018303 ft; ?,: -if- NO G-3^03 _ __DES CRIPTION _VAPORIZER G-3101 G-3I02. VCM TRANSFER VCM TRANSFER .0.-3201 0-3202 PURE. VCM .CHARGE RECD MONOMER CHARGE G-45 03 _ REC'D_ MONOMER . RE C IRC 5-4' OU REACTOR .CHARGE C.-4: OlB .REACTOR.CHARGE 0-3 SLURRY TRANSFER 0-4 SLURRY TRANSFER 412C 2 MONOMER TRANSFER ,412(6 JONOMER TRANSFER 412 ( 5_ VAPORIZER FEED _ 412(7 _VAPORIZER_FEED___ *413( 6_ 4132 0 com REACTOR CHARGE COPLYRECOV1D MONOMER RECIRC 411C 3 413: 5 413:3 4132S . CO PLY _REC'D __M3 NOMER _CHARGE PVC_REC iD_ MO NOME R_CHARGE PLASTISOLREC ' DJMDNOMER.CHAR! FVC MONOMER CHARGE *4131 6 *4181 8 418(! 44 416( 5 418: 418: 6 .PLASTISOLJ.'A''. FUME. SCRUBBER.. .PLASTI SOLJBJ_FUME_S C RU B BER HOMOGENIZATION FEED "A^ HOMOGENIZING HOMOGENIZAT10N PEED "B HOMOGENIZING J)EI -_604_ _DEI_-_603 _ _____DOUBLE MECHAN ICALS EA LS ____ DOUBLE . ME CHANICAL. S EA I PRELIMINARY PROJECT SCOPE DEI - 603/604 DOUBLE MECHANICAL SEALS BURLINGTON/FLEMINGTON The intent of this project is to reduce personnel exposure to VCM by the installation of double mechanical seals on monomer service pumps. Double Mechanical Seals - the seals are to be installed on all monomer service pumps. See Attached Sheet. Pressure Pots - to provide the sealing media of glycerin and water with a pressure of 15-20 LBS above that of the stuffing box @ 85 LBS a seal pot must be provided on each of the above installations. The pressur ization is to come from the existing plant nitrogen system and provide a minimum pressure of 125 LBS. Instrumentation - in order that we may prevent damage to the seal body or pump from loss of pressure or sealing media we will install pressure sensing instrumentation,;capable of shutting down the pump. Electrical - The pressure switches mentioned above are to be wired into the pump control circuitry to prevent starting and running of the pump under a low pressure condition. Approx. Cost $2500 per installation Burlington 21 pumps $53,000 Flemington 10 pumps $25,000 COLOR!TE 018304 On April 7, 1976 a Design Parameter meeting was held with Manufacturing representatives from both Burlington and Flemington. The following standards for double mechanical seal implementation were specified. 1) Seals are to be capable of being pressurized to 125 psi. 2) Assembly to be of the cartridge type. 3) Standardized on l$j" X 1 3/4" seal diameters. 4) Maximum allowable temp to be generated by seal of 120F, 5) Maximum of 2-3 cc/hr of glycerin to leak into dump cavity. 6) Seal manufacturers representative to be on site during installation of test seals. The following seal manufacturers were contacted and were requested to participate in the test seal program. 1) Crane 2) Durametallic 3) Chempro (Sealol) 4) Chesterton Arrangements were made with the Burlington site to enable the seal installations to be put on our worst service pumps that being copolymer. After numerous delays we began this program. Our initial tests with Buna n and Viton "0" rings ended in failure whereby we began using Kalrez "0" rings which enabled us to keep the seal running. The only exception to this was the Chempro seal which because of its Bellows construction did not experience the "0" ring failure. After our preliminary go around, the second generation of seals were tested with the following findings. 1) Durametallic Seal was ruled out after second test because of high temperature generation in the seal. 2) Crane Seal was ruled out after second test because of high temperature generation in the seal. 3) Chempro Seal has been in test for approximately four (4) months with only one excursion above 10 ppm, once the "0" ring swelled the system has maintained a maximum of 3-5 ppm leakage.4 4) Chesterton Seal has been in test for approximately four (4) months and has maintained a 0-3 ppm leakage. COLORITE 0X8305 In conclusion this department feels, that the Chesterton 241 Seal should be installed on all future seal installations, In order for Tenneco to meet the EPA requirements. It should be noted that we have choosen the Chesterton Seal over the Chempro although both have performed satisfactorily. The reasoning behind this decision is that the Chempro Seal is constructed with metal Bellows which have always been plagued with fatigue problems caused during cavitation or startup torques. This was not experienced during our testing but could occur over, long periods of running. COLOR!TE 018306 COMPARISON TABLE CHEMPRO (676) COST MAX PRESS TEMP. $750.00 300 PSIG LIMIT OF "0" RING A) BUNA N -40 F to 225 F B) VITON 0 F to 400 F C) KALREZ -40 F to 600 F EXCHANGE PROGRAM NO CAN BE REPAIRED IN HOUSE YES FRETTING NONE REACTION TO HARMONIC FATIGUE AVG RESPONSE TO TORQUE AVG PRODUCT BUILDUP IN BELLOWS DURING SHUTDOWN CARTRIDGE TYPE YES GUARANTEE AGAINST DAMAGE TO PUMP NO REACTION TO SHOCK IN CAVITATION AVG SELF ALIGNING CAPABILITIES AVG CHESTERTON (241) $713.00 400 PSIG LIMIT OF "0" RING -40 F to 225 F 0 F to 400 F -40 F to 600 F YES YES NONE GOOD GOOD t MIN YES YES GOOD EXCELLENT COLOR!TE 018307 PRICE CHANGE - "KALREZ" PERFLUOROELASTOMER PARTS Prices for KALREZ (formerly ECD-006) perfluoroelastomer parts are going to increase, effective January 31, 1977. During our first three years of commercial business, we had been able to resist inflationary pressures. Now, however, we must make some upward adjustments but did want to give you as much notice as pos sible. More quantity differentials have been added to provide additional price reductions for orders for larger quantities. Conversely, premiums for very small quantity orders have been increased. All orders placed by January 31, 1977, will be honored at present prices. We will be pleased to send you copies of our new price lists if you will just indicate your interest and return the attached request card or call us if you have an immediate need. We are also updating our mailing list so please fill out the balance of the card so that we keep your name in these records. This will help us get pertinent information in your hands now and as it develops. * ' 9 Great things are happening with KALREZ. Daily we hear from someone who has used a KALREZ part to solve a particularly dif ficult temperature or chemical resistance problem. They are truly becoming "the elastomer parts to use when nothing else works." We do appreciate your interest and if we can help at any time, don't hesitate to get in touch. Att. P. John B. Knox Product Sales Manager E. I. DU PONT DE NEMOURS & COMPANY (INC.) . ELASTOMER CHEMICALS DEPARTMENT. E353312 WILMINGTON, DE 19898 (302) 772-4095 or 772-3434 Trademark TELEX 835-420, WILMINGTON, TE Pnoted m u s COLORITE 018308 STEVEN M. OGINTZ KALRE2r ParfluoiWattomsr Parta COLOR!TE 018309 Chemical Resistance Guide for DU POflT Chemical Resistance--General Du Pont KALREZ perfluoroelastomer (formerly des ignated ECD-006) is an outgrowth of the chemistry that yielded VITON** fluoroelastomer and TEFLON** fluorocarbon resins. KALREZ combines many of the elastomeric properties of VITON with the chemical and heat resistance of TEFLON and provides certain advantages over both. Because of the difficult compounding and processing necessary in fabricating parts of KALREZ. Du Pont alone man ufactures and sells finished parts. This bulletin has been prepared to provide assistance to the design engineer in determining the suitability of KALREZ parts for service in chemical environments. KALREZ perfluoroelastomer parts possess out standing chemical resistance. When using appro priately formulated compositions, almost all classes of chemicals, with the exception of fluorinated sol vents, exhibit little or no measurable effect on KALREZ parts. Exposure to fluorinated solvents will induce moderate swelling and slight loss of physical properties (even so, KALREZ parts may provide bet ter service than other elastomers). Because of their excellent resistance to swelling by most chemicals, KALREZ parts resist permeation by these same (ma terials. In addition, KALREZ maintains its chemical resistance at operating temperatures far above those of other elastomers. KALREZ parts can func tion continuously at 500-550F (260-288C) and in termittently to 600F (316C). This combination of chemical and thermal resistance makes KALREZ es pecially suitable for service in hot, corrosive environ ments including: Polar solvents (ketones, esters, ethers) Strong organic solvents (benzene, dimethyl formamide, Perclene', tetrahydrofuran "THF") Inorganic and organic acids (hydrochloric, nitric, sulfuric, trichloroacetic) and bases (hot caustic soda) Strong oxidizing agents (dinitrogen tetroxide, fuming nitric acid) Metal halogen compounds (titanium tetrachloride, diethylaluminum chloride) Hot mercury/caustic soda Chlorine, wet and dry Inorganic salt solutions Fuels (ASTM Reference Fuel C, JP-5 Jet Fuel, aviation gas, kerosene) Hydraulic fluids (Skydrol 500 A1, Pydraul 3122. Anderol L-7743, and transmission fluids) Heat transfer fluids (Dowtherm A)4 Trademark "Reg US I'ademark of Du Pont 1 U $ Trademark of Diamond Shamrock Chemical Co. 2 U S Trademark of Monsanto Co. 3U$ Trademark of Tenneco Chemicals 4 U S. Trademai < o-` Dow Chemical Co Oil well sour gas (methane/hydrogen sulfide/ carbon dioxide/steam) Steam Chemical Resistance Tables Information on the resistance of KALREZ to specif ic chemical reagents is provided in Table I and to proprietary fluids and blends in Table II. The rat ings in these tables are based on the best compo sition of KALREZ for the given chemical exposure. We emphasize that the table should be used as a guide only and suggest that careful consideration be given to the following factors: For the great majority of products listed, the rat ings are based upon results of complete immersion tests, and, therefore, are conservative. In actual service only one-side or limited-edge exposure to fluids is normally experienced. KALREZ exhibits exceptional thermal stability and is serviceable at continuous temperatures to 500-550F (260-288C) and intermittent tempera tures up to 600F (316C). Because of laboratory constraints, many of the tests reported in the at tached tables were conducted at temperatures far. below the maximum service temperature for KALREZ. Therefore, test results should not be con strued to indicate either the maximum service tem perature or maximum duration at which KALREZ will remain serviceable in a given environment. In laboratory tests, many elastomeric materials show excellent chemical resistance to pure rea gents. However, they may fail in actual service because of chemical attack by additives and/or impurities in plant process streams. KALREZ per fluoroelastomer, with its near universal chemical resistance, provides extra insurance against these potentially unknown corrosive influences. Design Considerations As with all elastomers, specific compounding of KALREZ is needed to achieve the most suitable material. Factors considered in the selection of the optimum compound include chemical environ ment, service temperatures, operating pressures and essential physical properties. In many cases, part design has been found to be as critical as Inherent chemical resistance in achieving a functional and economical part. Du Pont engineers will carefully consider all of the parameters in designing finished parts for your specific applications. It is normally advisable to subject prototype parts to either simulated or ac tual service testing to verify chemical resistance and functionality of design. COLOR!TE 018310 RATING SYSTEM A--Shows little or no effect after exposure to the Du Pont for advice in specifying KALREZ for specified reagent as listed. Slight swelling (less these environments. than 10%) or loss of properties may occur under X--KALREZ is unsuitable for service in the envi severe conditions but this should not affect performance. ronment as specified. ( )--The bracket has been used around a rating B--May be affected by the specified reagent af letter, exposure temperature and exposure time ter exposure as listed, as evidenced by slight where no data are presently available on the ef visible swelling and/or loss of physical proper fect of the reagent on KALREZ. Based on simila ties. KALREZ* perfluoroelastomer can be ex rities of the test chemicals and our long-term ex pected to perform adequately in such service for periences with both KALREZ and VITON. some time period. Oftentimes, KALREZ will op Du Pont chemists would expect KALREZ to ex erate in such environments long after other hibit chemical resistance as indicated by the elastomers would have failed. Please consult bracketed letter and test conditions. TABLE I--CHEMICAL REAGENTS Chemical Exposure Temperature r c Exposure Time Dsys Rating Acetaldehyde Acetamide Acetic Acid. 10% Acetic Acid, Glacial Acetic Acid. Glacial (400) 122 75 428 Acetic Anhydride Acetone Acetonitrile Acetylene Acetylene Tetrabromide 113 113 113 (75) Acrylonitrile Ammonia, Anhydrous Ammonium Hydroxide, 35% Amyl Acetate Amyl Alcohol 75 75 113 (75) (212) Aniline Benzaidehyde Benzene Benzene Benzoic Acid (300) (75) 113 (158) Benzophenone Benzoyl Chloride Benzoyl Peroxide Boric Acid, 10% Boric Acid, 10% (212) 104 212 Butanol Butanol Butyl Acetate Butyl Carbitol Butyl Carbitol Butyl Cellosolve Butyraldehyde Butyric Acid Carbon Disulfide Carbon Tetrachloride 113 (250) 113 113 (250) 113 104 (75) 113 Chlorine, Liquid, Dry Chlorine, Liquid, Dry Chlorine. Gaseous, Dry Chloroacetic Acid, 10% Chloroform 140 (212) 75 104 75 Chlorosulfonic Acid Chromic Acid. 10-50% Cyclohexane Cyclohexanone Dibenzyl Ether o-Dichlorobenzene Diethylaluminum Chloride Diethylamine Diethylene Glycol Diisobutyl Ketone (75) 75 (75) (300) 75 (75) Dusopropyl Ketone Dimethyl Formamide Dimethyl Sulfoxide Dinitrogen Tetroxide Dioctyl Phthalate 75 75 160 113 Dioxane Ethanol Ethanol Amine Ethyl Acetate Ethyl Acetoacetate (75) 113 113 75 113 'Trademark **Rag, U.S. Trademark or Du Pent (204) 50 24 220 45 45 45 (24) 24 24 45 (24) (100) (149) (24) 45 (70) (100) 40 100 45 (121) 45 45 (121) 45 40 (24) 45 60 (100) 24 40 24 (24) 24 (24) (149) 24 (24) 24 24 71 45 (24) 45 45 24 45 (3) 100 28 60 100 100 100 (28) 8 240 100 (7) (5) (7) (3) 100 (28) (7) 30 4 100 (4) 100 100 (4) 100 30 (28) 100 7 (5) 150 30 28 (7) 600 (5) (28) 28 (10) 28 28 8 100 (3) 100 100 28 100 (B) (A) A A B A A A (A) (A) A A A (A) (A) (A) (A) A (A) (A) (A) (A) (A) A A A (A) A A (A) A B (B) (A) B A (A) A A A (A) (A) A (A) (A) (A) (A) A (A) (A) (A) A A A A (A) A A A A Chemlcil Ethyl Ether Ethylene Chlorohydrin Ethylene Diamine Ethylene Dichloride Ethylene Glycol Ethylene Glycol Ethylene Oxide 2-Ethyl Hexanoic Acid Fluorine Gas Fluobonc Acid Formaldehyde Formic Acid. 12% FREON** fluorocarbon products (partially halogenated e.g. F-22, F-23) FREON** fluorocarbon products (fully halogenated e.g F-11, F-12, F-13, F-113, F-114) Furfural Glycerine Glycolic Acid Glyoxal. 40% n-Heptane Hexafluoroisopropanol Hexamethylphosphoramide Hexane Hexanol Hexanol Hydrazine Hydrate Hydrazine. Unsymmetrical Dimethyl Hydrobromic Acid Hydrochloric Acid, 10% Hydrochloric Acid, 20% Hydrochloric Acid, 37% Hydrochloric Acid, 37% Hydrofluoric Acid, 75% Hydrogen Peroxide, 90% Hydrogen Sulfide (see also sour gas) Hydroxyacetic Acid Isophorone Isophorone Isopropyl Acetate Isopropyl Alcohol Kerosene Kerosene Lactic Acid Mercury/Caustic Methanol. 50% Methanol, 100% Methyl Butyl Ketone Methyl Cellosolve Methyl Chloride Methyl Ethyl Ketone Methyl Isobutyl Ketone Methylene Chloride Monochlorobenzene Naphtha Exposure Tempereture F "C Exposure Time Days Rating 113 104 113 113 (250) (158) 113 45 40 45 45 (121) (70) 45 104 212 (75) 40 100 (24) 100 30 100 100 (5) (5) 100 30 7 (7) (A) B A A A (A) (A) A (B) (A) A B (B) 75 24 10 X (158) (250) (70) (121) 113 45 75 75 (75) 113 (158) 75 24 24 (24) 45 (70) 24 (28) (5) 100 4 28 (21) 100 (7) 10 (A) (A) (A) A (A) A A (A) A (A) A 75 104 113 (230) 75 (158) (212) (270) (270) 24 40 45 (110) 24 (70) (100) (132) (132) 113 (158) (75) (75) 113 (400) (158) 200 104 113 45 (70) (24) (24) 45 (204) (70) 93 40 45 113 (175) 150 (75) (158) 45 (79) 66 (24) (70) 336 30 100 (14) 28 (7) (5) (D (7) 100 (7) (7) (21) 100 (40) (7) 360 30 100 100 (8) 70 (30) (28) A A A (A) A (A) (A) (A) (A) (B) A (A) (A) (A) A (A) (A) A A A (A) (A) (A) A (A) A (A) (A) COLORITE 018311 Chemical Nitric Acid, 70% Nitric Acid, 70% Nitric Acid. 70% Nitric Acid, fuming p-Nitroaniline Nitrobenzene o-Nitrochlorobenzene Oxalic Acid. Dilute Oxalic Acid, Cone. Perchloroethylene (Perclene') Perchloroethylene (Perclene') Phenol Phenol Phenylene Diamine Phosphoric Acid, 60% Phosphorus Pentachloride Phthalic Anhydride Propionaldehyde Propylene Glycol Pyridine Sodium Hydroxide, 10% Sodium Hydroxide, 46% Sodium Hydroxide, 46% Steam Steam Steam Steam Sulfuric Acid. 50% Sulfuric Acid, 60% Sulfuric Acid, Cone. Sulfuric Acid, 30% Oleum Tetrachloroethane Tetrahydrofuran Titanium Tetrachloride Toluene Exposure Temperature *F c Exposure Tims Days Dating 104 40 158 70 212 100 75 24 75 24 436 225 75 (212) 113 (300) 450 (212) (400) 75 104 75 113 75 (158) 212 390 450 509 75 (250) 113 122 (75) 75 75 75 24 (100) 45 (149) 232 (100) (204) 24 40 24 45 24 (70) 100 199 232 265 24 (121) 45 50 (24) 24 24 24 30 7 4 123 600 5 28 (28) 100 (28) 60 (28) (1) 28 30 28 100 7 (7) 28 28 28 365 28 (28) 100 270 (21) 600 2 600 A A B A (A) A A (A) (B) A (A) A (A) A (A) (A) (A) A A A A A (A) A A A A A (A) A A (A) A A A t U.$. Trademark of Diamond Shamrock Chemical Co 2U.S, Trademark of Tenneco Chemicals 3 U.S. Trademark of Mobil Oil Corp. 4 U.S. Trademark of Dow Chemical Co. 5 U.S. Trademark of Monsanto U.S. Trademark of Stauffer Chemical Co. Chemical Trichloroacetic Acid, 10% Trichloroacetyl Chloride Trichloroethane Trichloroethylene Trichloroethylene Triethanolamine Trifluoroacetic Acid Vinyl Acetate Water (also see steam) Xylene Exposure Temperature "F c Eiposure Tima Days Rating 104 75 (212) 104 (158) 40 24 (100) 40 (70) 30 28 (28) 30 (28) 165 113 194 (158) 74 45 90 (70) 6 hrs. 100 100 (28) A A (A) B (B) (A) B A A (A) TABLE II--PROPRIETARY FLUIDS & BLENDS Automatic Trans Fluid Andarol 1-7742 ASTM Ref. Fuel B ASTM Ref. Fuel C Avrex 2563 Aviation Gas Dowtherm 209* Dowtharm A* Gasoline, unleaded Jet Fuel Type II Jet Fuel JP-5 Jet OH II Kerosene Kerosene Pydraul 312C& Skydrol 500AS Sour Gas (methane/ hydrogen sulfide/ carbon dioxide/steam) 600 psi Stauffer m2 OII3 302 400 75 (75) 212 113 212 500 150 204 24 (24) 100 45 100 260 600 75 392 212 113 (400) 212 212 450 316 24 200 100 45 (204) 100 100 232 70 7 7 (7) 28 100 28 180 3 7 42 28 100 (40) 28 28 6 A A A (A) A A A A (A) A A B A A (A) A A B 212 100 28 A RATING KEY A--Little or no effect. B--Should be suitable depending on service conditions. X--Unsatisfactory. ( )--Estimated to belong in noted category. Du Pont--Problem Solver on Finished Parts Due to the difficult compounding and processing necessary to fabricate this unique elastomer, Du Pont has assembled a special laboratory and en gineering staff to work directly with potential endusers in an attempt to fill their needs for high-per formance elastomeric parts. We believe, that for most new applications, pro totype testing is the best way to go. To this end, Du Pont is ready to work with you in determining whether a KALREZ* part will solve your problem. Obviously, there must be a special need to justify the cost for KALREZ. But that is where KALREZ stands out--because there are many jobs that just can't be done satisfactorily with any other material. You are invited to submit drawings and/or specifi cations for price quotations. For further information, please call or write: E. I. DU PONT DE NEMOURS & CO. (INC.) ELASTOMER CHEMICALS DEPARTMENT E 353312 WILMINGTON. DELAWARE 19898 (302) 772-4095 or 772-3434 The Du Pont Company assumes no obligation or liability for any advice furnished by it, or results obtained with respect to this product. All such ad vice is given and accepted at the buyer's risk. Du Pont warrants only that the material itself does not infringe the claims of any United States pat ent; but no license is implied nor is any further pat ent warranty made. 'Trademark E*10034 Printed in U.S.A. COLORITE 0183X2 Technical Bulletin KALREZ (formerly ECD-006)--The elastomeric analogue of TEFLON' fluorocarbon resin provides exceptional fluid and high temperature resistance and extends the use of elasto mers beyond current application limits. KALREZ parts, standard and custom fabricated, are available from Du Pont. F atures Exceptionally inert--virtually unaffected by most chem icals--an elastomeric TEFLON. Thermally stable--usable at temperatures 100-200F (3893C) above those for VITON1 fluoroelastomer, silicone, fluorosilicone, acrylates. Durability--suitable for long-term service at 500-550F (260-288C) and intermittent service to 600F (316C). Du Pont--Problem Solver on Finished Parts--Special de sign team assistance from concept to finished part. Benefits Reduced downtime Reduced maintenance Simplified design Increased service life Description Du Pont KALREZ perfluoroelastomer is an outgrowth of the chemistry that produced VITON fluoroelastomer and TEFLON fluorocarbon resins. KALREZ combines many of the elastomeric properties of VITON and the chemical and heat resistance of TEFLON with certain advantages over both. KALREZ provides the end-user with elastomeric parts that are serviceable continuously at temperatures in excess of 500F (260C) and intermittently to 600F (316C). It is vir tually unaffected by almost all chemical agents. KALREZ is synthesized from monomers which are very costly to pro duce. Its compounding is complex. Consequently, the base price is many-fold more expensive than for VITON, Because of the chemical inertness of KALREZ, both the base polymer and the compounded stock are extremely difficult to manu facture and fabricate into useful finished parts. As a result, Du Pont alone designs, produces, and sells KALREZ parts, both standard and custom fabricated. G n ral Physical Properties Table 1 provides a brief summary of physical properties for some of the more commonly used compositions of KALREZ. Compounds 1050 and 3018 are widely used, general purpose compositions suitable for most mechanical parts. Com pound 1064 is a plasticized version of 1050 and offers im proved elongation properties. Compound 3065 is a more highly reinforced version of Compound 3018 offering im proved tensile properties, at some sacrifice of extensibility, under both ambient and elevated temperatures. Table 2 lists typical miscellaneous engineering properties of interest to design engineers. Similar to other fluorinated and perfluorinated polymers, KALREZ possesses excellent resist ance to the adverse effects of the environment, including sunlight, ozone and weather. 'Trademark *R9 US Trademark of Du Pont TABLE 1 General Physical Properties COMPOUND 1064 1050 3018 3065 Hardness, Durometer A 100% Modulus', psi MPa Tensile Strength', psi MPa Elongation at Break', % Compression Set, ASTM D 395B Pellets 70 hr @ 400=F (204=C), % @ 550F (288C), % Brittle Point ASTM D746, F =C 70 80 90 900 1,400 1,900 6.20 9.65 13.10 95 _ - 2,100 1.900 2,660 2.600 14.48 13.10 18.34 17.92 170 130 120 60 45 N.A.* 38 53 36 50 47 N.AT -42 -35 -35 -20 -41 -37 -37 -29 'ASTM D412, 10"/mtn, 'Not Applicable TABLE 2 Miscellaneous Engineering Properties (Compounds 1050 and 3018) Specific Gravity 2.02 Linear Coefficient of Thermal Expansion Over the range of 77-482F (25-250C) using the equation: L = U(1+oc^t) =. i.78 x 10'V = F =3.2 x 10'*/C Specific Heat (by DSC) Cp, 122F( 50 = 0 = 0.226 cal/g Cp, 212 = F (100C)= 0.233 cal/g Cp, 302F (150C)= 0.252 cal/g Electrical Properties Dielectric Constant (t) at 1,000 Hz Dissipation Factor (D) at 1,000 Hz D. C. Resistivity (p) Dielectric Strength (Breakdown potential) 4.9 5 x 10'5 5 x 10"7 ohm-cm >450 volts/mil COLORITE 018313 Thermal Stability KALREZ* perfluoroelastomer possesses excellent thermal stability. Table 3 presents data for samples of KALREZ 3018 that were aged in hot air for up to 504 days at 450F (232C) and 7 days at 600F (316C) as well as intermediate conditions. As shown by both laboratory and field testing, various com positions of KALREZ provide excellent long-term sealing ca pability at elevated temperatures. Figure 1 shows the retained sealing force of KALREZ O-rings as a function of time at ele vated temperatures. KALREZ O-rings retain sealing capa bilities in excess of 700 days at 450F (232C) and up to 60 days at 500F (260C) in air. Compression set data for pellets are shown in Table 1. Al though these high temperature test results are good, com pression set testing (Method B, ASTM D395, 25% deflection) is not a reliable predictor of the sealing properties of KALREZ at elevated temperatures because of the product's unique thermal stability and its exceptionally high coefficient of thermal expansion. Sealing force test methods (Figure 1) are preferred. TABLE 3 Long Term Heat Aging-- Compound 3018 Property Original SD4 Days 450F 123ZC| 112 Days 500F (260C| 28 Days 550F (288q 7 Days 6Q0F [316-C1 100% Modulus,1 p$i MPa 1,900 13.10 950 6.55 980 6.76 900 1,010 6.20 6 96 Tensile Strength,' psi 2,660 2,450 2,440 1,630 2,030 MPa 18.34 16.84 16.82 11,24 13 99 Elongation1 At Break 120 220 240 320 230 Hardness, 90 86 87 86 87 Durometer A 'ASTM D412. Chemical Resistance KALREZ exhibits exceptional resistance to nearly all classes of chemicals with the exception of some fluorinated mate rials. Some of the more difficult to handle chemicals and their effect on KALREZ are listed in Table 4. Of special note is the outstanding resistance to oil field sour gas, polar solvents (ketones, ethers, and esters), commercial solvents (tetrahydrofuran. dimethyl formamide), oxidizing and reducing agents, fuels, hydraulic fluids, heat transfer fluids, and steam. Figure 2 shows how little the physical properties of a compo sition of KALREZ have been effected after extended expo sure in a difficult chemical service. More details can be found in the more extensive "KALREZ Chemical Resistance Guide". "Trademark TABLE 4 Resistance of KALREZ to Selected Chemicals Chemical Temp. F c Acetic Acid, glacial Acetic Anhydride Acetone Ammonia, Anhydrous Benzene Boric Acid, 10% Butyraldehyde Carbon Tetrachloride Chlorine, Gaseous, dry Chloroacetic Acid, 10% Dimethyl Formamide Dimethyl Sulfoxide Dinitrogen Tetroxide Dowthgrm A' Ethyl Acetoacetate Ethylene Dichloride Formic Acid, 12% Freon2, fluorocarbon products fully halogenated Hexamethylphosphoramide Hydrazine Hydrochloric Acid, 10% Isophorone Jet Fuel, JP-5 Mercury/Caustic Soda Methanol, 100% Methyl ethyl ketone Nitric Acid, 70% Nitrobenzene Skydrol 500A2 Sodium Hydroxide, 10% Sour Gas* Steam Steam Sulfuric Acid, 30% Oleum Tetrahydrofuran 75 113 113 75 113 212 104 113 75 104 75 75 160 500 113 113 212 75 75 75 113 113 392 200 113 113 158 75 212 113 450 390 509 122 75 24 45 45 24 45 100 40 45 24 40 24 24 71 260 45 45 100 24 24 24 45 45 200 93 45 45 70 24 100 45 232 199 265 50 24 Time. Olyt 28 100 100 240 100 4 30 100 150 30 28 28 8 180 100 100 7 10 28 336 100 100 42 360 100 100 7 600 28 100 6 28 365 270 600 Ritleg' A A A A A A B B A A A A A A A A B X A A A A B A A A A A A A B A A A A RATING KEY A--Little or no effect B--Should be suitable depending on service conditions X--Unsuitable UJ.S Trademark--Dow Chemical 2 Reg US Trademark--Du Pont Co 3U S Trademark--Monsanto * Mixture of methane/hydrogen sulfide/carbon dioxide/iteam at 600 psi COLOR!TE 018314 FIGURE 1 Effect of Service Temperature on O-Ring Seal Durability Method ISO/DIS 3384 AS-568A-113 O-Rings, 25% Compression Compositions and Design Considerations As with all elastomers, specific compounding of KALREZ is needed to achieve the most suitable balance of properties for a specific application. While this bulletin provides data on only a few of the more commonly used compositions of KALREZ, many additional compositions are available to achieve desired end-use performance. It is the purpose of this review to make users aware that KALREZ* parts are avail able in various compositions to meet differing needs. How ever, this is not to suggest that the user specify a particular composition--nor are the physical property data to be inter preted as a specification. Du Pont is best equipped to select compositions when complete specifications on the appli cation have been provided. The Du Pont design team of engi neers and chemists will select the most appropriate composi tion for the intended service based on a complete evaluation of critical design parameters including chemical environ ment, service temperatures, operating pressures and essen tial physical properties. Trademark COLORITE 018315 Parts Availability Both standard and custom parts, molded, calendered, ex truded or otherwise processed, are available. Standard Parts, made to tight tolerances include: Sheeting O-Rings Slabs Rodding Tubing Septa Reinforced Sheeting Reinforced Slabs Custom-Made Parts, with physical properties tailored to meet specific end-user requirements include: Electrical Connectors Fluid-Sealing Components Flange Seals Gasket Stock Liners Pipe-Coupling Seals Pump Diaphragms Pump Liners Roll Covers Valve Seals & Seats Wire Coverings Du Pont--Problem Solver on Finished Parts Due to the difficult compounding and processing necessary to fabricate this unique elastomer, Du Pont has assembled a special laboratory and engineering staff to work directly with potential end-users in an attempt to fill their needs for fin ished elastomeric parts. (Information on applications for KALREZ* parts is available in a separate report, E07259.) We believe that for most new applications prototype testing is the best way to go. To this end, Du Pont is ready to work with you in determining whether a KALREZ part will solve your problem. Obviously, there must be a special need to jus tify the cost for KALREZ. But that is where KALREZ stands out--because there are many jobs that just can't be done sat isfactorily with any other material. You are invited to submit drawings and/or specifications, including full details on chemical environment, service tem peratures, operating pressures, and essential physical prop erties, for price quotations by the Du Pont KALREZ design team. The Du Pont Company assumes no obligation or liability for any advice furnished by it, or results obtained with respect to this product. All such advice is given and accepted at the buyer's risk. Du Pont warrants only that the material itself does not infringe the claims of any United States patent: but no license is implied nor is any further patent warranty made. E. I. DU PONT DE NEMOURS & COMPANY (INC.) ELASTOMER CHEMICALS DEPARTMENT E353312 WILMINGTON, DELAWARE 19898 (302) 772-4095 or 772-3434 Trademark 6*10033 Printed in U S.A COLORITE 018316 Product Profile Du Pont KALREZ perfluoroelastomer (formerly ECD-006) Is composed primarily of fluorine and carbon. It combines many of the properties of a fluoroelastomer (l.e. Du Pont VITON * * fluoroelastomer) with thoseof a perfluorlnated plas tic (i.e. Du Pont TEFLON** fluorocarbon resins). It provides certain advantages over both. KALREZ Is synthesized from monomers which are very costly to produce. Its compounding Is complex. Conse quently, the base price is manyfold that of VITON fluoro elastomer. And, because conversion into finished parts involves unusual processing, Du Pont alone designs, produces and sells KALREZ parts, both standard and custom fabricated. Features of KALREZ Perfluoroelastomer Parts... KALREZ parts have mechanical properties similar to other fluorinated elastomers but exhibit greater heat resistance and chemical inertness. KALREZ parts have thermal, chemical resistance and elec trical properties similar to TEFLON fluorocarbon resins but, made from a true elastomer, possess excellent resistance to creep and set. Generally, KALREZ parts are capable of providing continu ous service at temperatures Of 500-550F (260-288C) and can operate at 600F (316C) for shorter periods. Their chemical resistance is outstanding. When using specially formulated compositions, little or no measurable effect is found in almost all chemicals, excepting fluorinated solvents which induce moderate swelling. The parts have excellent resistance to permeation by most chemicals. Resistance to attack is especially advantageous in excep tionally hot, corrosive environments such as: Polar solvents (ketones, esters, ethers). Strong commercial solvents (tetrahydrofuran, dimethyl formamide, Perclene\ benzene). Inorganic and organic acids (hydrochloric, nitric, sul furic, trichloroacetic) and bases (hot caustic soda). Strong oxidizing agents (dinitrogen tetroxide, fuming nitric acid). Metal halogen compounds (titanium tetrachloride, diethylaluminum chloride). Hot mercury/caustic soda. Chlorine, wet and dry. Inorganic salt solutions. Fuels (aviation gas, kerosene, JP-5 Jet Fuel, ASTM Reference Fuel C). Hydraulic fluids (Skydrol2 500A, Pydraul2 312, Anderol3 L-774, and transmission fluids). Heat transfer fluids (Dowtherm A4). Oil well sour gas (methane/hydrogen sulfide/carbon dioxide/steam). Steam. 1 u S Tradamar* ot Diamond Shamrock Chemical Co, 2 u S Trademark uf Moi santo Co 3 U S Trademark of Tenneco Chemical 4 0 S Trademark of Dow Chemical Co Trademark *Meu. 0 $ Trademark of Du Pont Benefits of Use of KALREZ Parts... Increased Service Life The useful life of a part can often be increased manyfold by making it from KALREZ, Reduced Downtime Replacing less durable materials with KALREZ is buying long term protection against part failures that result in shutdowns, ruined equipment or unsafe opera tions. KALREZ provides extra protection at extreme service temperatures that degrade lesser polymers. KALREZ parts are ideal for those maintenance situations where shutdown costs are large in relation to the parts cost involved. When Nothing Else Works Often, in highly critical situa tions, when no other material would function, a KALREZ part has met the need. New Design Possibilities KALREZ parts, with their unique properties, often open new design possibilities and oppor tunities for system simplification that can reduce overall costs. However, a direct shape substitution of KALREZ for a part made from plastic, metal or another elastomer may not always be satisfactory. Rather, a cooperative study must sometimes be made with the design engineer to tailor the shape of the part to the requirements. In many cases, this results in more desirable engineering design, with one KALREZ part replacing a more complicated part or several component parts. KALREZ parts should be considered to increase parts re liability and increase safety. This can result in important benefits such as reduced maintenance costs, extended equipment life, reduction of production interruptions and reduction of weak links in systems. Industries Served... Since the start of test marketing KALREZ parts in mid-1972, many different types of parts problems have been studied. Economic factors have ruled out KALREZ for some applica tions while many others are under development. The rest comprise a rapidly growing list of successful commercial uses of KALREZ. Oil Fields KALREZ parts are providing improved compo nents for equipment used in oil wells previously considered impractical to recover. Such wells are plagued with highly corrosive hydrogen sulfide under unusually heavy pressures and high temperatures. One application, specialty boots for electronic logging, was the first commercial usage of KALREZ. Among other oil field applications now commercial or being developed are; insulation sleeves for electric connectors, O-rings, chevron packings, shaft seals, packings and insu lated wire for downhole use. Aerospace The mechanical properties of KALREZ parts, combined with their resistance to jet fuels, kerosene, ben zene, isooctane, and such oxidizing agents as dinitrogen tetroxide and fuming nitric acid have stimulated considerable developmental and commercial activity in O-rings, bladders, and miscellaneous seals. COLORITE 018317  Analytical and Process Instruments One of the most demanding applications for KALREZ* is as injection port septa for liquid chromatographs. The near universal chemical resistance of KALREZ allows the liquid chromatograph user to easily switch from one to another solvent stream without changing septa. KALREZ resists most common solvents, in cluding acetic acid, alcohols, aromatic organics, hexane, ketones and tetrahydrofuran, while maintaining self-sealing properties after repeated punctures by hypodermic needles. In gas chromatography, the thermal stability of KALREZ septa to temperatures in excess of 300C (572F) provides outstanding resistance to septa bleed (the evolution of vola tiles from the septa, which interferes with sample analysis) and out-gassing under high vacuum. The combination of thermal stability, chemical resistance and out-gassing resistance has led to the expanding use of KALREZ parts (diaphragms, gaskets, O-rings, and seals) in process instruments and valves in severe services, such as ammonia, chlorine, hydrochloric acid, sulfuric acid and tetrahydrofuran. Chemical Process and General Industry KALREZ perfluoroelastomer is particularly useful in industry for main tenance parts that must withstand the effects of high heat and/or harsh chemicals. KALREZ parts are being used in equipment operating in chemical and thermal environments which quickly degrade other elastomers... or where TEFLON has been used previously for chemical and thermal stability but where elastomeric sealing characteristics are more desirable. Some of the more severe environments in which KALREZ has solved difficult sealing problems include: heat transfer fluids at 500 F (260C), nitrochlorobenzene at 440 F (227C), hot polyesters at 500F (260C), and caustic/chlorine at 200F (93C). In one instance, switching to large KALREZ O-rings in heavy duty compressors has dramatically reduced downtime which costs the user about $100,000 a day in lost production. Electrical/Electronic Due to their excellent dielectric strength, KALREZ parts offer great potential as electrical in sulators and connectors for oil-field equipment and sophisti cated electrical appliances operating in hostile environments. Printed electronic circuit boards have been successfully produced using rolls covered with KALREZ, submerged in a 550F (288C) oil-solder bath to squeeze off molten solder. The Du Pont company assumes no obligation or liability for any advice furnished by it. or results obtained with respect to this product. All such advice is given and accepted at the buyer's risk. Du Pont warrants only that the material itself does not infringe the claims of any United States patent: but no license is implied nor is any further patent warranty made. Availability of Parts... Both standard and custom parts, molded, calendered, ex truded, or otherwise processed, are now commercially avail able from Du Pont. Standard Parts, made to tight tolerances include: Sheeting Tubing O-Rings Septa Slabs Reinforced Sheeting Rodding Reinforced Slabs Custom-Made Parts, with physical properties tailored to meet specific end-use requirements, can be compounded with a variety of fillers, and include: Electrical Connectors Pump Diaphragms Fluid-Sealing Components Pump Liners Flange Seals Roll Covers Gasket Stock Valve Seals & Seats Liners Wire Coverings Pipe-Coupling Seals A Departure... Rarely does a raw polymer manufacturer assemble a special laboratory and engineering staff to work directly with poten tial end users in an attempt to fill their immediate needs for finished elastomeric parts. Due to the difficult compounding and processing necessary to fabricate this unique elastomer, Du Pont, in this instance, is making such an individualized service available. We invite you... We believe that for most new applications, prototype testing is the best way to determine the suitability 6f a KALREZ part. To this end, Du Pont is ready to work with you in determining whether a KALREZ part will solve your problem. Our special research and application team of chemists and engineers will study your problem. You are invited to submit drawings and/or specifications for price quotations. To receive other information or for an answer to a question related to your specific needs, please call or write: E. I. DU PONT DE NEMOURS & COMPANY (INC.) ELASTOMER CHEMICALS DEPARTMENT E 353312 WILMINGTON, DELAWARE 19898 (302) 772-4095 or 772-3434 Trademark 07259 COLORITE 018318 Printed In U.S.A. "KALREZ" PARTS IN CHEMICAL SERVICE Chemical Service Acrylonitrile Air Ammonia, Anhydrous Ammonia, Liquid, Dry C02 Chlorine, Gas, Wet Chlorine, Liquid Chlorine, Gas, Dry Chloro-Acetyl Chloride 3,4-Dichloro Aniline Fuming HCL Heat Transfer Fluids Mercury/Caustic Methyl Methacrylate Methylene Chloride Mixed Liquids (Hydrazine, Ammonia, Sulfides) Mixed Liquids (MIBK, Organics, HCL) NaOH, HjO, Chlorate Nitric Add, 90% Nitrochlorobenzene m-Phenylene Diamine Polyester Polymerization Process Steam Sour Gas (H2S, CO2, H20, etc.) Styrene Sulfuric Acid, 30% Oleum Sulfuric Acid, 10-20% Sulfur Trioxide THF Toluene/MEK/MeCIa Xylene Conditions RT1, >14 Days 316C (600F), 1,000 hrs. RT1, >4 mos. RT1, 240 Days 249C (480F), 450 psi >360 Days RT1, 180 Days RT1, 150 Days RT1, 240 Days 70C (158F), 90 Days 130C (266F), 30 Days RT1, 180 Days 260C (500F), >180 Days RT1, 270 Days RT1, >90 Days 66C (150F), >10 Weeks 66-93C (150-200F) >12 Weeks 66-93C (150-200F) >12 Weeks 93C (200F), >3,000 hrs. RT1, >123 Days 225C (437F), >115 hrs. 230C (446F), >2 mos. 288-316C (550-600F) >5 mos. 265C (509F), >1 yr. 260C (500F), 20,000 psi RT1, >3 mos. 50C (122F), >9 mos. 82C (180F), 180 Days 50C (122F), >9 mos. Boiling RT1, >100 hrs. 121C (250F), >3 mos. Parts O-Rings2 Spark Plug Boots O-Rings O-Rings O-Rings Diaphragms, O-Rings O-Rings O-Rings O-Rings O-Rings O-Rings O-Rings Diaphragms, O-Rings O-Rings2 O-Rings O-Rings2 O-Rings2 O-Rings O-Rings Pump Seal O-Rings2 O-Rings O-Rings2 Electrical Connectors, O-Rings O-Rings2 O-Rings2 Diaphragms, O-Rings2 O-Rings2 Valve Seats O-Rings2 O-Rings2 The above listing summarizes some of the successful applications using KALREZ parts in severe chemical environments. In almost all cases indicated by an indeterminate duration (e.g., >360 days), the KALREZ parts were still functioning at the end of the time period and maximum service life has not y t been established. In many cases, maximum service life of the system is now being determined by limitations other than the life of the rubber seal. Trademark 'RT - Room Temperature 2No Other Elastomer Works E. I. DU PONT DE NEMOURS & COMPANY (INC.) ELASTOMER CHEMICALS DEPARTMENT. E353312 WILMINGTON, DE 19898 e 10587 (302) 772-4095 or 772-3434 TELEX 835-420, WILMINGTON, DE Printed m U S COLOR!TE 018319 HOW "KALREZ" PERFLUOROELASTOMER PARTS CAN SAVE YOU MONEY ON YOUR SEALING NEEDS Elastomeric parts such as O-rings and other seals made from KALREZ perfluoroelastomer, the "rubbery" TEFLON, offer many opportunities to reduce the total operating cost of equipment used in the chemical process industry (CPI). KALREZ parts are higher priced than similar parts made from other elastomers. However, where the need exists, they can be the lowest cost in service. Savings from the use of KALREZ parts can normally be achieved by: 1) reduced maintenance costs as a result of the greater service life attainable through the use of KALREZ: 2) reduction of downtime caused by equipment outages; 3) reduced initial cost due to greater design freedom; and 4) greater safety. SOME CASE HISTORIES WHERE "KALREZ" PARTS ARE HELPING TO SAVE MONEY Investment of $300 Results in Savings of $2,000.00 A chemical plant has eight pumps used for Dowtherm A1 at 246C (475F), pumping 5,000 gallons per minute. Mechanical seals using O-rings for the secondary seal were failing on the average every two months. Maintenance costs ran about $1,000 for each failure. An investment of $300 for KALREZ O-rings has resulted in more than tripling of service life between overhauls, and a resultant seven-fold payback. No pumps have failed to date because cf the KALREZ O-rings. Equipment Operation Extended from 3 Weeks to Over 5 Months A polyester film plant uses a mechanical seal on a mixer operating at 280-316C (536-600F). O-rings on the seal failed on the average every 3 weeks. KALREZ O-rings have been in service for over 5 months without failure. Operating Where Lost Production C uld Cost $100,000.00/Day A carbon dioxide compressor operates at 244C (470F) and 100 psig. Silicone O-rings were failing in a short time and lost production could run as 1 U.S. Trademark of Dow Chemical Co. much as $100,000/day. KALREZ O-rings hav now been in service for over a year and a half and are still functioning. Saving $1,000 Per Seal A pump handling para-nitrochlorobenzene at 150C (302F) required a metal bellows seal that cost nearly $2,400. This has been replaced with a conventional seal, using KALREZ O-rings, which cost only $1,400, a significant savings. Eliminating a Fire Hazard A pump handling heat transfer oil at 220-240C (428-464F) used a conventional stuffing box which allowed leakage. A fire occurred which damaged the pump and other equipment. The pump was replaced with one using a mechanical seal with KALREZ O-rings thus eliminating the leakage and potential fire hazard. Extending Instrument Life Over 35 Times Instruments in a sulfuric acid plant exposed to sulfur trioxide at 50C (122F) and 30% oleum at 50C (122F) needed replacing on a weekly basis because of O-ring failure. Instruments fitted with KALREZ O-rings have been in service for mor than nine months without replacement. Call or write us at the address below to find out how KALREZ parts can help you save money. E. I. DU PONT DE NEMOURS & COMPANY (INC.). ELASTOMER CHEMICALS DEPARTMENT. E353312 . WILMINGTON DE 19898 E'105fl6 (302) 772-4095 or 772-3434 TELEX 835-420, WILMINGTON, DE p COLORITE 018320 Select O-rings carefully Seldom visible O-rings are often present in process machinery sealing applications. Observe these guidelines to make them work for you, not against you Male lm G. Murray Jr., Murray & Garig Tool Works, Baytown, Texas In hydrocarbon processing plants, mechanical seals for pumps and compressors, tube fittings and pipe flanges often use O-rings to prevent fluid flow or leakage. Accord ing to application, O-rings can be categorized as static (seal between flange facings) and dynamic (subjected to movement or wobble). See Fig. 1. Table 1 lists the com monly available O-ring materials and their characteristics. Chemical compatibility of O-rings with a process fluid and temperature limits will define the method of O-ring production, using full-circle molding, ambient adhesive bonding and hot bonding or vulcanizing. Having no joint, hence no weak point, reliable in operation, full-circle, molded O-rings are the most common. Available in a wide range of stock sizes and materials, O-rings of this type also can be custom-molded. Ambient adhesive bonded O-rings of any diameter can be quickly and easily made, using cord stock of most materials except silicone rubber. A simple jig used for cutting square ends and aligning them for bonding gives a smooth joint, which can some times be made in place without machine disassembly. Vulcanizing is considered to be an intermediate method in terms of nonstock O-ring delivery, chemical and tem perature resistance. Thermal and chemical resistance of the hot, bonded O-rings are superior to the adhesivebonded but inferior to the molded. O-ring failure analysis can be instructive to prevent machine failure. I will now discuss several common causes of O-ring failure. Deterioration in storage. Some synthetic rubbers such as neoprene and buna N are sensitive to ultraviolet radia tion, others to heat and ozone. Storage in a cool, dark environment, away from electrical equipment, is therefore recommended. i Fig. 1--Mechanical seal Installation with static and dynamic O-rings. Temperature. Exceeding an allowable temperature is a common cause of O-ring failure (see Fig. 2). The largest O-ring failed from overheating because of blockage of seal flush. The inner one did not recover from compres sion set at high temperature, remaining "flattened out" as shown. The two lower rings failed because of overheating or chemical attack. Table 1 lists temperature limits for common O-ring materials. These limits can often be ex ceeded for short periods. Process fluid temperature may not be equal to O-ring temperature. A cool flush may reduce O-ring temperature, as may heat dissipation through a barrier structure. On the other hand, localized frictional heating may increase the O-ring temperature. If high or low temperatures are suspected as causing failure, it may be practical to change the environmental temper ature or the O-ring material. In extreme cases, an allmetal bellows seal may permit elimination of O-rings. Mechanical damage. Tearing, pinching, foreign matter embedment, dry rubbing and various other mechanical Ruprinted from HYDROCARBON PROCESSING, April 1976 Copyright t*7S by Gulf Publiihiiig Co., Houston, Texas. All rights iwcvtd. Used with pormission. COLORITE 018321 SELECT O-RINGS CAREFULLY Fig. 3--0-rlng tool Kits. damage can occur during installation, operation and re moval. A sharp steel tool used for O-ring removal can scratch the groove or sealing surface and cause leakage. Brass, wood or plastic tools can be used without risk of scratching. Fig. 3 shows two O-ring tool kits. The twopiece kit on the left is made of brass, the five-piece kit on the right, having rounded tips and edges, is made of stainless steel. Chemical attack. Table 1 is useful in selecting O-ring materials compatible with various fluids. Experimental verification is sometimes worthwhile. Complications may occur because of different properties of supposedly iden tical O-rings produced by various manufacturers. Also, a loss of identification in storage and handling is possible. To minimize unpleasant surprises for critical service such as hot xylene, we routinely discard new O-rings which come with new and rebuilt seal assemblies, and replace them with O-rings of known material from a single manu facturer considered reliable. To check whether an un known, used O-ring is Viton or something else, we use the carbon tetrachloride test described in Table 1. Ab ut tha author Malcolm G. Murray, Jr., ts owner of Murray & Garig Tool Works, Baytown, Texas. He designs and manufactures machinery alignment, grouting, tank in spection and rescue signaling equipment for oil refineries, chemical plants and marine applications. Mr. Murray holds a BS. degree in mechanical engineering from Duke University and an MS. m mechanical engineering from Stanford. He was a machinery test engineer m the US. Army Corps of Engineers, Ft. Belvoir, Va, He was then a construction project engineer and a machinery mainte nance and procurement engineer with a major overseas oil refinery before forming his own firm. He is a member of ASME and is a registered professional engineer in the Dis trict of Columbia and Texas. He has several patents on machinery alignment devices and plastic sunlight reflectors. COLORITE 018322 ou>.ucit(M NU.a-^Ol-j J Serl Sitter MARKH \ -\K,/- Pressure Sensitive Switching Device For Protecting Mechanical Seals . Explosion-Proof Construction All Wet End Parts are made of TFE O ADJUSTMENT SCREW V, 1*4.250-J conoiht 4.031 2SI DIA MOUNTING HOLES (2) PUCES PRESSURE PORT H N.PT. 'The John Crane Seal-Sitter Mark II automatically protects mechanical seals, impellers and other sensitive pump components against damage as the result of dry running conditions. It can be readily installed in a system so as to instantly shut off operation and/or actuate an audio or visual alarm when a pressure drop occurs. The Seal-Sitter Mark II pressure switch is adjustable within a range of 6 to 340 PSIG at temperatures from --65 to +160* F. Enclosure is explosionand tamper-proof. All wetted parts contacting the fluid are made of TFE to permit the handling of practically any chemical or corrosive. The Seal-Sitter is especially valuable in systems engaged in batch system transfer cycles, loading or unloading tanks and vessels or similar operations. It also protects against maintenance failure in systems dependent on flow through a filter or where an independent flushing source is used. Other applications are protection of installations using double seals or throttle bushings. WIRING DIAGRAM ON REVERSE SIDE COLORITE 018323 SEE OPTION 1 ENCLOSURE: Explosion-proof (NEMA 7,9) designed to the requirements of hazardous loca tions Class I, Groups C & D and Class II, Groups E, F & G. Tamper-proof ex ternal adjustment. ELECTRICAL CHARACTERISTICS: Underwriters' Laboratories, Inc. listed single pole double throw snap-action switching elements. Electrical rating (continuous inductive) 10 amps 125 or 250 volts AC, 3 amps 480 volts AC, .5 amps 6 volts DC, .5 amps 24 volts DC. Automatically reset by snap-action of switch. Class J switch element with elastomer boot around actuator and sealed to prevent moisture and foreign matter from affecting contacts. ELECTRICAL CONNECTION: Through Vi " NPT conduit connection to screw terminals on switch. PRESSURE CONNECTION: %" 18 NPT internal thread. ADJUSTMENT INSTRUCTIONS: Loosen set screw with a #10 Allen wrench. With screwdriver, turn adjust ment screw clockwise to raise and counterclockwise to lower the actua tion point. Tighten set screw after de sired setting is reached. SHIPPING WEIGHT: 2% lbs. (approx.) NO -t>---co NC ii ii -J ! _ jI UNIT "A Low Pressure High SEE OPTION 2 START 1 =P" STOP PUSH BUTTON STATION TO POWER SUPPLY r OoCE NC 0_ UNIT "S' NO I J Hllh Pressure J i UNIT "A": Low Pressure ____ J (Push button must be held on start up until Switch A is closed by Pressure) UNIT "B": High Pressure OPTIONS: 1. High or low pressure circuit audio or visual alarm. 2. Low pressure cut out only (install jumper). High and low pressure cut out (remove jumper). Switches can be used in combination to effect a warning signal on initial pressure decrease, then shut off if pressure drops to critical level. OPERATING CHARACTERISTICS All values given In P.S.I. (Gauge) Proof Press. Adjustable Range Decreasing Increasing Min. Max. Min. Max. Approx.* Actuation Value (Differential) 2000 6.0 331.5 7.0 340.0 1.0-8.5 `Fixed at any pressure setting. Varies as shown from lowest to highest setting. CRANE PACKING COM PAN V 64-00 OAKTON STREET, MORTON GROVE, ILLINOIS 60053; (Chicago Subuibt In Canada: Crane Packing Company* Ltd., Box 3243; Station C, Hamilton. Ont. In Mexico:- Industrial John Crane de Mexico, 5.A., * Poniente 152 .`679 industrial Vallejo.. Mexico* D.F, tn Brazil: John Crane Industria E Comercio, Ltda. * Avenida Jurubatuba 600; Sao Bernardo do Campo. S.P*In Australia: John Crane Mauri Pty.,, Ltd.. 166 Etdridge Road. Bankstown, New South Wales, Australia In Europe: Crane Packing Ltd.. Slough, Bucks, England In Japan: John Crane Japan. Inc.. No, 28, Tsuboya-cho 2-chome; Kita-ku, Osaka 530* Japan*. OFFICES, WAREHOUSES- AND SERVICE THEWORLD OVER' - v' S COLOR!TE 018324