Document N2aZao0Qg2g0ebwE337r5Dgap

r' n o FELLOWSHIP REPORT ATI-99 MYRIL C. SHAW RESEARCH FELLOW ASBESTOS TEXTILE INSTITUTE PHILADELPHIA TEXTILE INSTITUTE PHILADELPHIA, PA. REPORT #37 June h, 1956 MS 004212 MT-003618 PRODUCED JM-83 } ATI-99 THE ELEVATED TEMPERATURE SERVICEABILITY r OF ASBESTOS TEXTILES UNDER COHSTAiJT STRESS Introduction Asbestos textiles are frequently placed in service under the combined condi tions of elevated temperature and load or stress. The ability of these materials to resist destruction as a result of a constant or intermittant application of a load or stress may often serve as the prime factor in determining its suitability for a given service. Curtains, draperies and temporary or movable partitions where in the materials are supported at the top and permitted to hang more or less free from that support, are examples of such services. Under these conditions the stress may be the result of the weight of the cloth itself or may consist of a combination of the cloth weight plus a roller or other super structure which may be attached to the bottom of such a curtain. Tapes and cloths used as lagging materials may be tightly wrapped or applied over a pipe or cable and with an increase in temperature the expansion of the pipe or cable may be greater than that of the tape or cloth, putting a stress on the lagging material. There are innumerable other applications in which, at some stage in the performance of a service, asbestos textiles are called upon to resist destruction due to stress while serving as a non-combustible protection medium. The industry has for many years accepted an arbitrary range of temperature limits of serviceability for the various grades of asbestos textiles available, as follows: o Commercial Grade Underwriters Grade Grade A Grade AA Grade AAA Grade AAAA -- Up to i*00F --H -- " i(50OF It 5oF -- ii it 600F -- 'I ii 750F -- ii 900F This system of grading is based solely upon asbestos content and does not take into account such important factors as cloth construction and design or stress bearing characteristics. Yarn construction and cloth constructions are very closely related and the grades of fiber or the lengths of asbestos fibers used will exert some Influence upon the resultant elevated temperature serviceability characteristics. For example, a 36P10 cloth may contain fibers which are predominately of 3R quality, however, when a cloth bearing the construction of 17P2lj. is required the asbestos fiber quality may need some improvement in grade and fiber length if the requisite 2k cut yarns are to be produced for incorporation in this latter cloth. Such improvements in fiber quality usually reflect improvements in several properties including elevated temperature serviceability. In an effort to determine the relative elevated temperature characteristics of a group of asbestos textiles designed to meet specific applications, some con sumers have directed attention to so-called heat-aging tests as a means of r\ evaluation. In such tests the textiles are subjected to a predetermined heat treatment, some at 200F, others at f>72F and some at higher temperatures for periods of time ranging from 30 minutes to several hours and following such treatments are tested to determine the loss in tensile strength resulting from MT-003619 PRODUCED JM-83 MS 004213 ATI-99 -2- the heat treatments. Such heat aging tests do serve a useful purpose in that the results usually reflect to some degree the fiber quality which was used in the cloth construction and on the basis of comparative tests a consumer may be able to establish which of several cloths so tested e:chibit the characteristics which will best serve the intended application. However, it is doubtful that the results of such tests provide simulative service data of universal signi ficance since the time cycle of test is much shorter than most service applica tions, Further, the stress is applied after the sample has been permitted to cool to room temperature following the heat treatment while in service the stress would undoubtedly be active during the heating up period as well as the cooling period. The selection of arbitrary temperatures and periods of duration for these tests limits the data resulting therefrom to specific areas of serviceability which in most cases will not serve to define either the maximum or minimum para meters of serviceability. In an effort to overcome some of the indicated short comings of heat aging tests as they are currently conducted it was felt that a study wherein asbestos textiles subjected to live loads continuously at elevated temperatures might provide data that could be interpreted in terms that would serve to define the ranges of elevated temperature serviceability as a function of the tensile strength properties at these temperatures. The work covered in this report re presents the initial undertaking in this investigation and, although the data cavers only a relatively few cloths and tapes and cannot therefore be considered with any degree of finality, it does provide some interesting relationships which serve to indicate the trends that may be ejected in the more extensive study being pursued. Testing Equipment The equipment used in this investigation was designed and built specifically for this study. The main unit of the equipment set-up is the electric furnace wherein the samples under test are subjected to elevated temperatures. The furnace has over-all outside dimensions, 21;" long by 11;" wide by 10" deep and inside dimensions, l" long x 5" wide x 5" deep. The heating elements, consist ing of two coils of nichrome wire, each rated at 1000 watts at 110V and each be ing capable of separate control, are embedded in the two side walls of the furnace. The furnace is constructed with a one-inch ;rilde slit running length-wise along the center of both the top and bottom sections of the furnace so that the samples of cloth under test may be supported above and outside of the furnace, passed through the furnace and extend six inches below the bottom of the furnace, at which point loads may be attached to bottom of the sample. The furnace was constructed on wheels so that it could be moved along a track-way. The purpose of the movable feature was to provide the possibility of carrying out shock tests wherein the furnace might be first heated to a given temperature \rilthout test samples and upon the attainment of that temperature be moved in place over the test specimens, under a given load. In this manner heat shock or instantaneous heating tests are to be conducted. The airdliary equipment necessary for the operation of the furnace consists of a Powerstat Variable Transformer for controlling the power input, a voltmeter to indicate the voltage input and a potentiometer equipped with a chromelalumel thermocouple for measuring the temperature attainments, PRODUCED MT-003620 JM-83 MS 004214 ATI-99 -3- The furnace was originally designed to operate at a maximum temperature of l00F, however, in actual usage the practical limit of operation was found to be U+15F. The heating schedule is set forth in Plate I, Test Procedure The procedure followed in carrying out the tests in this investigation re presents a departure from that pursued in most heat aging tests currently in use. Tensile strength characteristics serve in both instances as the factors of significance, however, in the normal heat aging tests grab test specimens are studied while in the work here undertaken 1" ravel-strip samples 21" long are used. The samples must be 21" in length in order that they may extend through the test furnace being supported above the furnace and extending below the furnace sufficiently to accommodate the desired loads. The segment of each specimen that is actually subjected to the heat treatment is approximately 7 inches. The test samples are first prepared by cutting representative specimens 21" long by 1-1/2" wide, and then ravelled to a 1" width. The tensile strength of the ravelled sample is then determined using the prescribed technique for strip tests, with 2" jaws both front and back, top and bottom, on the tensile tester, with the top and bottom jaws 3" apart. The tensile strength so determined serves as the basis for stress applicationand is noted as the "Tensile Strength, As Received", The load or stress to which each of the samples is subjected is based upon the "As Received" tensile strength in increments of 10$, 20$, 30$ and $0$ of the original strength. In carrying out a given test, two specimens are mounted in the furnace at one time and are loaded with respective weights, determined as above noted. The furnace is then engaged and the temperature permitted to rise according to the schedule set forth on Plate I untilthe samples have broken as a result of the combined high temperature and load, the temperature at the time of rupture being noted. Presentation of Results The results of the tests conducted thus far in the investigation are tabulated in Table I and are also set forth in Plates II, III and IV, Table I presents the specific data relating sample number, style, tensile strength, as received and, in the last four columns, the temperatures and loads at failure. In explanation of the presentation of the data in the last four columns, refei' to sample T-l and it will be observed that in the column designated 10$ load the figures are presented as 920/21 which indicates that at 21 pounds load, which is 10$ of the as received tensile strength for that particular sample, the tape failed at 920F, Likewise under 20$ load or U2 pounds, failure was induced at 5l5F, The figure preceeding the hash mark denotes temperature of failure and the figure following the hash mark denotes applied load. MT-003621 produced JM-W MS 004215 -i;TABLE I ATI-99 Sample Style Number Tensile Strength 1" Ravel Strip As Received (Except Tapes) 10 Failure Temperature F Pounds Stress/ 1" Ravel Strip Percent Load/As Received 20 30 50 Commercial T-l T-5 T-22 T-2U 199 Tape l"x.0638 Ix.0675 Ix.0633 1x.14o4 U0P10 Underwriters 209.16 128,00 113c66 287.00 102.00 920/21 515/42 915/13 615/26 705/11s3 565/22.7 1060/28,7 725/57.4 1040/l0,2 515/21.4 440/63 490/39 495/34.0 570/86,1 425/31.6 375/105 390/64 440/57.0 500/143.5 400/51.0 T-3 T-7 T-9 T-ll T-13 T-15 T-30 243 271 Tape Ix.l4l5 lx, 0728 lx. 082lj. lx.0321 lx.090 lx.1688 lx.0633 n?2k 17P26 261 198 178 100 209 317 99.2 60.0 55.33 970/26 1145/20 680/18 1065/10 1175/21 1440/9.9 1110/6.0 1090/5.5 685/52 975/40 605/36 915/20 990/42 1045/64 985/19.8 950/12.0 920/11,0 585/78 675/60 555/Sli 470/30 895/63 935/95 575/29.7 865/18.0 600/16.6 490/130 440/99 410/89 415/50 455/104 585/158 450/49.6 645/30 410/27.6 250 24P10 S-l 26P14 244 n 269 it 259 36P10 263 40P10 240 n 278 11 251 11 Grade A 203 260 36P10 11 Grade AA 246 36P10 S-2 11 275 11 274 29P14 192 40P10 50 68,0 55.0 79.66 99.00 109.0 104.0 88.33 91.33 90.0 79.66 68.0 96.7 84.66 80.0 82.0 975/5.0 780/10.0 1090/6.8 645/13.6 1030/5.5 615/11,0 1085/7.9 935/15.8 1080/9.9 905/19.8 1145/10.9 980/21.8 975/10,4 625/20.8 1190/8.8 950/17.6 1205/9.1 970/18.2 475/15.0 615/20.4 450/16.5 655/23.8 500/29.7 500/32.7 580/31.2 650/26.4 565/27.3 420/25 395/34.0 390/27.5 515/39.8 390/49.5 435/54.5 385/52.0 510/44.16 485/45.6 1185/9.0 990/18.0 600/27.0 485/45.0 1135/8.0 975/16.0 915/24.0 440/40.0 1410UF/6.8 1070/13.6 1030/20.4 14101IF/9.7 1195/19.5 1025/29.2 l4l0ilF/8.4 1135/16.9 1035/25.3 1410NF/8.0 1115/16 1005/24 1410IIF/8.2 1045/16.4 1025/24.6 900/34 860/48.3 930/42.3 855/40 900/41.0 produced All ' w MS 004216 MT-003622 Sample Style Number Grade AAA 2U7 36P10 257 ti 272 22P16 21*8 it 280 U8T12 X 1+8P10 ATI-99 -5- Tensile Strength 1" Ravel Strip As Received (Except Tapes) 10 Failure Temperature F Pounds Stress/l" Ravel Strip Percent Load/As Received 20__________ 30__________ 50 110.5 73oO 87.0 81,3 138,33 195 oO HaONF/lloO 1120/22,1. 1055/33.15 905/55.2 . HaonF/7.3 1050/1U.6 975/21.9 855/36.5 liilOHF/8.7 Hil0A7.U 1025/26.10 970/U3.5 li*10HF/8,,l 1180/16.2 1095/2U.3 965A0.6 litlONF/13.8 lijlONF/27.6 1365A1.7 1085/69.1 llaONF/19.5 1380/39.0 101*5/58.5 995/97.5 n n MIS MT-003623 PRODUCED ATI-99 UJt* PRODUC MT-003625 u. .6 2 z X o JM -83 MT-003626 m - 83 MT-003627 ATI-99 *10" In many of the higher grade cloths such as sample #2^6 under Grade AA it will be observed that the 10/2 figure reads lljlONF/6,8 which indicates that under 6,8 pounds load no failure (NF) was induced at liilO, the limit of the temperature rise. In this investigation eleven 1" tapes were studied, four in Commercial grade and seven in Underwriters Grade, each tape being identified by the letter T placed before the sample number. The remainder of the samples here studied were cloths in the variety of styles as shown. The graphic presentation as given in Plates II, III and 17 serves to illus trate the similarity in performance of most cloths having like styles and grades. Analysis of Results The results of this investigation offer some rather significant points of interest regarding the ability of certain asbestos textiles to resist destruc tion by stress at temperatures considerably above those normally accepted as the upper limits for elevated temperature serviceability, Before endeavoring to analyse the specific data as presented, it may be well to consider the magnitude of some of the values to be dealt with in this work. In the first place, the loading schedules established for each of the cloths and tapes here studied have been based upon the original or as received tensile strengths as determined upon samples tested in accordance with the ac cepted standard practice of having 3" between the jaws of the tensile tester. Under this particular test, however, the samples are subjected to tensile stress over a 19" span between the jaws. Experience gained during this work shows that the tensile strength as obtained over the longer span will be somewhat less than that obtained for the 3" span, A thorough investigation of this condition is to be undertaken, however, to date, nothing of a specific character can be given. It has been found that in some cases the tensile strengths over the longer span may be as much as 10^ less than that obtained for the shorter span. It must be realized therefore that when reference is made to the 10 load or other incre ments as noted, the load in pounds as set forth is, in all probability, actually somewhat greater than the percentage indicated, based upon the 19" span which is used. In an effort to correlate the applied loads with some characteristic of the materials here tested in order that a basis for comparison may be more apparent, the various loads as related to the unit weight of the cloths have been tabulated and are set forth in Table II, Here it will be seen, for example, that the ap plication of a load of 10# to a 17 ounce per square yard cloth, is equivalent to 3U0 times the weight of the sample. In other words, developing this data further, a load of 10# per inch applied to a sample of 17P2U cloth would be the equivalent of 360 pounds for a sample of the cloth a yard wide or 3ii0 times the weight of a yard of such a cloth. Likewise, a 22 ounce cloth , , loaded at 50# is the equivalent to 1310 times the weight of the cloth or lCOO pounds per yard wide sample. Also, a 36 ounce cloth (36P10) loaded at 50# is an equivalent of 800 times the cloth weight or 1600 pounds for a sample one yard wide. The full range of equivalents for loads versus cloth weights are set forth MS 004222 MT-003628 ATI-99 -11- in Table II and the relationships noted serve to indicate to some degree the magnitude of the stress values with which we are here concerned. Table II Weight Equivalents in Terms of Cloth Weights Loading './eight. Ounces Load Equivalents per Cloth Weight ji UA vn # 10 20 30 50 17 31*0 780 1120 22 262 52h 786 1310 2b 2h0 1*80 720 26 222 1ihh 666 36 160 320 1*80 800 ho 11*1* 288 U32 720 The test data as presented in Plates II, III and IV provide an opportunity to gain a comparative impression of the characteri sties of materials of like grades under the conditions of these tests. Plate II for example, covers the n performance data for 1" tapes in Commercial and Underwriters Grades in a variety of thicknesses. It will be seen that, in most cases, the Commercial Grade tapes exhibit somewhat inferior properties compared with the Underwriters Grade over the range studied. Under the maximum stress of $Cf/- of the original strength, the entire range of temperatures of failure is from 375F to 500F for the Com mercial Grades and from IilOF to 585F for the Underwriters Grade. Tape T-l which is in Commercial grade loaded at 105i/ failed at 375F while T--2JU, the heaviest of the tapes in this grade, loaded at 31*3.5# failed at 500F, This latter load, incidently, is the equivalent of 1025 pounds per square inch. The Underwriters tapes, under the maximum loading, ranged from 1*10F loaded at Cp pounds to 585F loaded at 158#, the latter tape being the heaviest of the tapes in this grade. It is significant to note that under the minimum loading or stress which xcLll be referred to hereafter as a "perceptable stress" the range of temperature over which failure was induced extended from 705F to 1060F for Commercial grades and from 680F to ll*l*0oF for Underwriters grade. On the other hand the ranges of failure at maximum or "appreciable stress" extended from 375F to 500F for Commercial grade and from l*10F to 585F for Underwriters grade. Plate III presents the performance characteristics of one Commercial and fifteen Underwriters Grade cloths under the conditions of this test. The Com mercial grade cloth, l*0P10, which is identified by the dotted line will be seen to exhibit somewhat inferior properties, compared with the entire group of Underwriters cloths, shoxfing approximately 10// lower failure temperatures than the average for Underwriters grades. The selection of Underwriters grade cloths here covered ranges from 17P2U through 1*0P10 For this variety of cloths the performance characteristics will be seen, from the curves, to cover a rather wide range. ' MS 004223 PRODUCED JM-83 MT-003629 ATI-99 -12- In general, however, the performances of the normal Underwriters grade cloths under the conditions of this test are reasonably well grouped and the demonstrat ion serves to indicate the characteristics which may be expected of such materials under stress at elevated temperatures. Under conditions of "Perceptable stress" (up to 10$ load) the serviceability temperatures for this group of cloths ranged from 975>F on sample w2$0 to 1190F for sample $270 and for conditions of "ap preciable stress" (up to 50$ load) the range extended from 385F for sample i(2U0 to 6U5F for sample ,"2lt3 . Plate IV sets forth the performance data for cloths in various styles and in Grades A, AA and AAA. The grade differences are noted on the graphs by the dif ferences in the continuity of the lines as noted in the legend on the Plate. In this work, two samples of Grade A, 36PIO cloths were studied and it will be seen that the performance characteristics of the two samples are quite similar and, as a matter of fact, close study will further reveal that these cloths fall well within the range of performance for the average Underwriters grade cloths. Cloths in Grade AA and AAA, hot/ever, exhibit elevated temperature perfor mance characteristics which are distinctly significant and which serve to reveal the unique properties of such materials. Under the conditions of these tests and applying the "perceptable stress" of 10$ load which ranged from 6.8$ to 19#!?;/ per 1" 3trip, there was no failure at 1U10F after heating for a period of 2 hours and minutes. Under the "appreciable stress", which ranged from 3kir to U8.3ir for Grade AA the failures ranged from C55F to 930F and for Grade AAA under the "appreciable stress" ranging from 36.5$ to 97.3;"' the range of failure was from 8f>5>F to 10u5F. Cloth $-2C0, i|8T12 in Grade AAA, e:iibited the most outstanding performance, showing no failure after 2 hours and US minutes, the time necessary to attain ll;10oF under a load of 27.6$ and under a stress of 69*1// this material remained in tact up to 108f>F. Conclusions The elevated temperature serviceability of an asbestos textile is dependent upon many factors aside from the cloth construction itself, and we are here parti cularly interested in the one related to the amount and kind of stress or physical abuse to which the material may be subjected. In order to properly service an installation it is necessary to be able to define with reasonable accurracy the several limits of serviceability so that materials capable of meeting the requirements may be properly adopted. MS 004224 PRODUCED JM-83 MT-003630 ATI-99 13' There are many applications which require materials that will simply resist destruction as a result of high temperature conditions and where there may be very little or no tensile stress. Under such conditions it would appear, on the basis of the preliminary work here reported, that some lower grade cloths will serve as effectively as some of a higher grade materials which might be indicated on the basis of current information. For example, most of the Underwriters grade cloths here studied exhibited reasonable strength and body retention at temperatures above 1000F under "perceptable stress" conditions. However, under conditions here termed as "appreciable stress", failures were found to range between U00F and 500F. The significance of the data thus far* developed in this work would seem to indicate that under conditions requiring minimum strength properties the service ability temperatures of all grades of asbestos textiles are well above the limits commonly recognized for such grades. As was pointed out earlier. Grades AA and AAA are extremely indestructable under minimum stress, resisting rupture at ll*10F under the conditions noted, although under the "appreciable" stress failure was induced at around 900F for Grade AA cloths and from 850F to 1100F for grade AAA cloths. In considering the xiork here reported it must be realized that these results xjere obtained under conditions of a constantly increasing temperature, with the rise continuing either until failure was achieved or the maximum capabilities of the furnace were reached. In addition, the duration of the tests were for reasonably short periods of time, in no case, exceeding 2-3/U hours. It is reasonable to assume that subjection of these sane materials under constant load and soaking at a constant temperature will bring about somewhat reduced tempera tures of serviceability, however, the magnitude of this reduction can only be ascertained through further study. Further xrork in this investigation will include the aforementioned soaking heat studies and instantaneous or shock tests wherein the samples -under load will be instantaneously inserted into the furnace which has been previously heated to and is being held at a high temperature. With the accumulation of the data which xri.ll be procurred from the three series of tests here to be undertaken, it should be possible to rather clearly establish and define the elevated temperature serviceability characteristics of the more universally accepted styles and grades of asbestos textiles presently available* Acknowledgment s With the conclusion of this academic year at the Philadelphia Textile Institute we are about to lose the services of Claude A, Kennedy, a student at the Institute, x*ho has served as our laboratory assistant throughout this year. We would like to appreciatively acknowledge his xxork and assistance in developing much of the data presented in this report for xiithout his help it would not have been possible to have advanced in this investigation to the extent here reported. MS 004225 PRODUCED JM -83 MT-003631 ATI-99 The Technical Committee held its Second Quarter Heeting on June lith, at the Hotel New Yorker, Hew York, Hew York, There were four member companies represented with six members present. IN ATTENDANCE: Raybestos-Manhattan, Inc, ii. W. Oliver, Chairman H. S, Maier - Johns-iianville Corporation J. L, Tucker Ed Beale Keasbey & Mattison Company R. L. Lanz Southern Asbestos Company J. D, HcCluer Philadelphia Textile Institute II, C. Shaw Since all members had received a copy of the minutes of the previous meeting, it was moved by llr. Tucker and seconded by Dr, Haier that the reading of the minutes be dispensed with at this time. It was recommended by the chairman that the Technical Committee send a proposal to the Board of Governors stating that the Asbestos Textile Institute award a plaque or scroll to I*r. C, R, Frederick, of Keasbey & Hattison Company, in recognition of his many years of service and contributions to the Institute, It was moved by Hr. J, L, Tucker, seconded by Hr. HcCluer, and unanimously approved by all members present this action be taken. It was further recor,mended in the proposal that President Wakem extend an invitation to Hr. C. R, Frederick to attend our next meeting so that the presentation could be made to torn at the General Heeting. This would be done if Dr. Shaw could get the scroll in time for our next quarterly meeting in September. Hr. R. L. lanz rendered the report of the Sub-Committee on Asbestos Tapes. There was no change in the status of the specification on industrial tapes. This is complete with the exception of after heating tensiles. There will be no action on this until a standard method for testing after heat tensiles of cloth and tapes can be adopted. The action taken to date on industrial tapes is covered in Table I, attached. During the past quarter, Hr. Lanz submitted a form to each member company to fill out on electrical tapes for the following gauges: .010", .015", .020", .025", and .030". The data submitted on these forms was discussed in detail, however, several large variations were found in total number of ends on the various widths. This was no doubt due to the different style yams used by the individual companies. As a result of this, it was agreed that we would attempt to standardize on the 1" width of each thickness tape and continue our work from that point. Hr. Lanz will send out forms requesting constructions and yarns to be used in manufacture of 1" tape. He will then use a formula presented, by the chairman and compute a nominal ft/lb., showing permissable range of yarns that may be used with reported constructions (total ends and picks/inch). Vie will then be able to re-evaluate our individual constructions and yarns to see if any change must be made to stay within tolerances. It was tentatively agreed that on 1" tapes the standard total number of ends and picks/inch would be as follows: PRODUCED MS 004226 JM - 83 MT-003632 pgg0 2 No, Ends 1" Width Picks/inch, All Widths THICKNESS, INCHES: ,010" .015" ,020" 31 33 28 17 15 13 .025" 32 12 ATI-99 .030" 33 11 FORMULA MENTIONED ABOVE IS AS FOLLOWS: (1,10 3) x Total Humber Ends Wt/lOO* r ' * yds/lbo (Warp Yarn) Warp (1,10 * 3) x Picks/inch x Width ** Wt/lOO* Filling ' yds/lb, (Filling Yarn) Wt/lOO* Tape The above formula is for non-metallic tape, no binders. In the case of binder warp, it is figured separate from ground warp and approximately 60^ contraction factor is used on binder warp instead of 10!- as is used on ground warp. This formula is to be used only as a guide and is not guaranteed to be 100n accurate. Brief discussion took place on tolerances in regards to total number of ends, picks/inch, gauge, etc. Since there were different values reported, there will be another discussion on this prior to writing them into A.S.T.M. specification to be recommended at a later date. This concluded the report of the Sub-Committee on Asbestos Tapes, both Industrial and Electrical, Since there was no activity in the Sub-Committee on Braided Tubing during the last quarter, there was nothing to report, however, a brief discussion took place on the type of gauge to be used in measuring thickness, Mr, Tucker sug gested the Cady gauge and it was requested that he send to each member company a detailed description of this gauge and where it could be purchased. It was agreed that even though we may not agree on a specific instrument, that we should set a standard as to the size of the anvil and the amount of weight to be applied. If we can standardize on this, then the Cady gauge, or its equivalent, could be written into the specification on methods of testing braided asbestos tubing. This subject will be on our agenda for the next meeting for further discussion* Mr, Cutler, Chairman of the Sub-Committee on Asbestos Cloth, was not pre sent. There was no activity within the committee on this subject during the last quarter as we were awaiting results from Dr. Shaw on dynamic testing of asbestos cloths. Our aim in regards to cloth is to standardize on a heat aging method for testing asbestos cloths. We are not in position to make a recom mendation at this time due to further work to be conducted by Dr. Shaw, There was a joint meeting with the Sales Promotion Committee in the afternoon at which time Dr, Shaw discussed this subject as a part of his Fellowship Report ,r31. In the place of dynamic testing, it is now termed "The Elevated Temperature Serviceability of Asbestos Textiles under Constant Stress", Dr. Shaw feels there is additional work to be done whereby cloths may be tested around 2,000F, for short periods. He is to write and request necessary samples from each member company so that tests can be made on current cloths. This subject is covered in detail in Dr, Shaw's Fellowship Report, therefore, nothing further will be reported here, however, each member company is to carefully digest the data reported by Dr, Shaw in the Fellowship Report as pertains to this subject MS 004227 MT-003633 PRODUCED Jill-83 Page 3 ATI-99 and will send to him their comments and recommendations. Dr, Shaw presented pictures of testing equipment used so that everyone would have a much better idea of his undertakings in continuing his work on soaking heat studies and shock tests at higher temperatures. A new oven must be constructed in order to reach the high temperatures for shock testing. This will be worked on during the third quarter. The next topic on the agenda was that of U, S, Government Specifications, In accordance with the request of the Technical Committee at the march meeting. Dr, Shaw contacted the Detroit Arsenal to find out what had happened to our proposed revision of iril-C-10316, made in 1951*. Hr, G, 0, Newcomb, Ordnance Tank-Automative Command, replied on 12 April 1956, as follows: "Gentlemen: Since the proposed revision to Specification IH1-C-10316 elicited considerable comment when coordinated with other agencies in the Department of Defense, it was never issued. These comraents are presently being incorporated into a further revised draft which, it is hoped, xri.ll be issued without further delay. Sire (6) copies of this revised draft trill be forwarded to your organization when it is submitted to Washington for issue," . (Signed) G, 0, Newcomb Assistant" During the past quarter, each member company xras to study Iiil-I-3053A, dated August 3, 1951, covering Insulation, Electrical, Asbestos Fiber, Treated and Untreated. Special emphasis was to be given to that part dealing xrith Di Electric strength. In checking our records it x*as found that a proposed revision was submitted in 195U, This proposed revision included a deletion of those parts pertaining to Di-Electric strength. Dr, Shaw has been instructed to write appropriate Government agency to determine the status of the proposed revision. Dr, Shaw will also state that we do not approve of Par, i*,5.i*,2 on Hagnetic Iron Content when required. Since we are not prepared to make a concrete recom mendation at the present time, action will be xrithheld until further consideration is given this subject. Report to be made at next meeting of our committee. This concluded action on U, S, Government Specifications, It was moved by lir. J, D, HcCluer and seconded by J, L. Tucker, that Dr, Shaw's project list be expanded to include better ways of determining dust in asbestos fiber, better methods of evaluating asbestos fiber, also, use of mild acid to remove impurities prior to making Water of Crystallization determination on asbestos fiber. Since expensive equipment would be required to carry on some of the above activities, it was recommended that the above be presented to the Board of Governors for appropriate action. It was recommended by ilr, J, L, Tucker that Dr. Shaw's project list be further expanded to include "Development of lietal Detector", for use on asbestos yarns, rovings, etc. Since Raybestos-Iianhattan's representative was opposed to such a project for the Secretary, and, stated they would not participate in this project, it will be presented to the Board of Governors for proper disposition. There being no further business, it x*as moved by Dr, liaier and seconded by Hr, Tucker that we adjourn. MS 004228 MT-003634 Respectfully submitted, produced M, W, Oliver, Chairman JM -83 ASBESTOS TEXTILE INSTITUTE Treasurer's Report August 30, 1956 ATI-99 Balance in Various Funds - May 28, 1956; Fellowship Fund General Fund Petty Cash & 18,288.25 8,1*06,76 57,28 26,752.29 Receipts: Exhibit Fund Travel Expense Refund $ 3,5oocoo 352,76 $ 3,852.76 Transfers: To Exhibit Fund (From General Fund) To Petty Cash (From General Fund) b it,000,00 92,50 $ U.Q92.50 b 3^9735 Disbursements: Fellowship Fund; Fellowship Grant (Phila, Tex. Inst.) $ 3,000.00 Fellowship Salary 3,177,33 Laboratory Expense _______ 7l*o95 b 6,252.28 General Fund: Secretary's Salary Stenographic Expense Meeting Expense Legal Expense Auditing Expense Ind. Air Hyg, Found. Survey Exhibit Transfer Travel Expense Advance Misc, Office Expense Petty Cash Transfer 6 1,009,09 158.00 286,68 53U.53 3,00 861**33 it, COO 0 00 62i*,6i* 173-67 92,50 & 7,71*6.1*1* Exhibit Fund: Art Guild Payments b 3,233.31* 0 3,233.3k Petty Cash Fund: Lab, Assistance Lab, Supplies Office Supplies BALANCE ON HAND, AUGUST 30, 1956 0 21.00 5.22 52.72 MS 004229 78.91* it 17,311.00 & 17,366.55 Balance in Various Funds - August 30, 1956: Fellowship Fund General Fund Exhibit Fund Petty Cash Fund b 12,009.75 1,039.30 it,266.66 70.81* 3 17,386.55 RODUCED JM -83 Respectfully submitted, J, G, Schoepf MT-003635 ATI-99 r FELLOWSHIP REPORT IffillL C. SHAW RESEARCH FEILOW ASBESTOS TEXTILE INSTITUTE PHILADELPHIA TEXTILE INSTITUTE PHILADELPHIA, PA. REPORT #38 September 6, 19i>6 MS 004230 r> MT-003636 PRODUCED JM -83 THE SERVICEABILITY OF ASBESTOS TEXTILES UNDER STRESS AT ELEVATED THiPERATURES ATI-99 Introduction The ability of a wide variety of materials of construction to withstand elevated temperatures under varying degrees of stress is causing no small con cern throughout many industries, particularly those responsible for the develop ment of the newer aircraft engines and atomic power plant units. Improved metals, cermets and oxides are being developed and investigated in an effort to increase the thermal resistance limitations presently inherent in the materials available. Asbestos textiles are likewise being called upon to serve in applications that not many years ago would have been considered untenable. The accepted upper limit of ?00F for AAAA Grade cloths and lesser temperatures for lower grade cloths has pieced a deterent in the consideration and application of many asbestos textiles for uses where temperatures in excess of 1000 F are re quired, However, certain investigators have successfully adapted asbestos textiles to applications where the temperature requirements were well in ex cess of the indicated maximum serviceability temperatures for those textiles. Recent work reported by the Fellow has indicated the possibility of higher temperature applications for certain asbestos textile constructions and in an effort to more specifically deter:,line the high temperature capabilities of these materials work has been pursued with investigations conducted at tem peratures up to 2650F, In considering this problem with its many implications and possibilities it will be appreciated "that to endeavor to establish and fix specific tempera ture versus grade relationships for a range of asbestos textile materials would be impossible and impractical. There are many factors which in combina tion will serve to determine the serviceability of an asbestos te:ctile, such as the grade of the material, the grade of chrysotile fibers used in fabricating the material and the weight, weave and construction of the material. Testing Uetiiod and Equipment The work conducted during recent months has been directed, for the most part, in an effort to determine for a few of the highest grade cloths, the maximum temperatures of serviceability under a "sensible stress" for perceptable periods of time. The term "sensible stress" is defined in this case as a load or stress of measurable proportions greater than the load which would be applied were tire cloth permitted to hang free wherein the load would be equivalent to the weight of the cloth itself but considerably less than the "as received" breaking strength. For example, a 2,25:- cloth will exert a stress of 2.25i" per square yard while hanging free which is the equivalent of approximately 0,9;" per square inch of supporting area. Likewise, a 2,50i!' cloth will exert a stress of approximately ,93<1? per square inch of supporting area. In applying the "sensible stress" an airciliary load has been added, to the test specimens to affect a stress on the 2.25i/; cloth equivalent to approximately 70/ per square inch of supporting area, and in the case of the 2.50/ cloth, approximately 65i<- per square inch. MT-003637 PRODUCED JM - 83 MS 004231 ATI-99 -2- n The ''sensible stress" here selected bears no relationship to practical application possibilities but was selected to conform with the limitations of the testing equipment adopted for this work. The test equipment selected for this work was developed primarily for exploratory purposes and was so devised that it might serve to determine whether or not further work along these lines is justified and if so how the stress and temperature applications might be best exerted and controlled. The test furnace consisted of a vertical, tubular muffle, 3" inside diameter by 3-1/2" deep, said muffle being encased in an insulating brick refractory shell. The furnace muffle was heated by means of an air-gas Meeker burner inserted in the bottom opening of the muffle. A temperature indicating Platinum-Platinum-Rhodium, thermocouple, mounted in the top of the muffle opening was so positioned that it would measure the temperature at the surface of the test cloth specimens supported across this opening. The cloth samples to be tested were supported in a metal bow frame so constructed that the samples, 1" wide by 20" long, could be mounted and, by means of a calibrated spring, be subjected to a known pull or stress. The sam ple so mounted was positioned that it would span the top of the furnace muffle opening. With the unit here described it was possible to attain and maintain tem peratures up to 2650F for controllable periods of time and served effectively to provide the information here to follow. However, if an extensive investi gation along the lines here pursued is to be undertaken it is recommended that a more substantial unit and one having greater testing capacity be provided. Test Results In an effort to explore the scope and possibilities of usefulness for data which might result from the work here to be undertaken, a variety of representative cloths were first investigated at a high temperature and a high stress in order to determine the upper limits of possible serviceability life. The first series of tests were run at 2$$0F at a stress exerted by a 20# pull and under these conditions the following results viere obtained. Style Grade Duration of test before failure. Seconds Stress Equivalents in pounds per square inch 22P10G Und, UOPIO Und. liOPIO Und, 36P10 A 29P11* AA 36P10 AA n UOPIO 22P16 AA AAA li8T12 AAA 12 12 13 12 11 7 22 10 28 570 266 266 286 3k5 286 MS 004232 266 392 266 MT-003638 PRODUCED JM-83 ATI-99 -3- It will be observed that the load or stress applied in all of these tests was 20,/, however, due to the differences in the thicknesses of the various cloths, the stress equivalents in pounds per square inch of supporting area are different for each construction. The results of the foregoing studies served to indicate that at the temperatures used a stress considerably less than 20,/ or per square inch equivalent will be necessary if significant life is to be obtained. The next series of experiments was therefore designed to determine the "sensible strength life" of a group of asbestos textiles at temperatures of 2500F and 265>0F, The cloths selected for this investigation were 36P10 style in Grades A, AA and AAA and style U0P10 in Grade AA, The "sensible strengths" selected were obtained by applying a 5,/ load or the equivalent of 71.!?;/ per square inch for the 36P10 and 66,6,/ per square inch for U0P10. Under these conditions the following results were obtained. Time of Failure liinutes 2500F 26$0F 36P10 A ii AA n AAA ItOPIO AA 8 no failure after 30 minutes ii ti less than 1 less than 1 2.25 U.50 Also investigated at this time were samples of Blue Asbestos cloth rea sonably comparable to 36P10 in style and failure was found to occur in less than 10 seconds at 2000F. In addition to the series of ultra-high temperature tests herebefore described, work was continued using the equipment and techniques as set forth previously. Report #37* wherein studies at moderately high temperatures up to 3-U75F were described. In this latest work, samples of 36P10 in Grades AA and AAA were positioned in the electrically heated test furnace under a stress of 8,5m (120;!! per square inch equivalent) for the Grade AA cloth and 11,0;!' (155;/ per square inch equivalent) for the Grade AAA. cloth. Under these condi tions of stress the test was started at 1000F and run continuously for one weekj there being no failure at the conclusion of this period, the tempera ture was increased to 1200F and run for a second week, following which the temperature was increased to 1U00F for a third week, to 1H50F for the fourth week and the test concluded with two additional weeks at lU70F, The over-all test consumed 6 weeks at temperatures ranging between 1000F and lii70F and at the conclusion of this test period there was no failure. However, the samples were permitted to cool down to room temperature in the furnace and under load and at some time during this cooling period failure did occur. The time and temperature of failure was not determined since it occurred during a period of our absence from the laboratory. This cooling failure is however important and more information in this regard is desired. It is undoubtedly a subject for thermo-mineralogical analysis and from such determinations we may be able to establish some fundamental data related to the elevated temperature weaknesses of the chrysotile fiber. WIT-003639 PRODUCED JM-83 MS ATI-99 Analysis of Results The ability of an asbestos textile to resist destruction due to stress at elevated temperatures is dependent upon a number of factors, including the properties and characteristics of the textile, and the temperatures and stresses to which it may be subjected. In general, however, the results here obtained would indicate that under the condition-3 of the3e tests at low or "sensible stress", that is, in the neighborhood of 100 pounds per square inch. Under writers Grade cloths will normally withstand destraction up to temperatures in the neighborhood of 900F to 1200F depending upon weight, weave and con struction of the cloth. Increasing the stress to 200 pounds per square inch decreases the temperature range to 600F to 900F and at 300 pounds per square inch stress the temperature range is further decreased to U50F to 650F. Cloths in constructions ranging from 29P1h to U0P10 in Grade AA were found to resist failure at a temperature of li*00F under a "sensible stress" approximating 10G# per square inch and additional tests at much higher tempera tures revealed that style 36P10 cloth in Grade AA would withstand the "sensible stress" for thirty minutes at 2500F without destruction. At temperatures of 050 - 900F failure was induced under stress somewhat greater than 500# per square inch. Cloths in Grade AAA were found to respond to these tests with proportion ately high serviceability characteristics. Under stresses equivalent to from 510# to 1200#' per scraare inch, failures were obtained at temperatures ranging from 800F to 1085F. It will be observed that in every instance, the cloths tested at a minimum load or what we have termed "sensible stress", the temperature of failure far exceeds the generally recognized temperature limits of service ability for the several asbestos cloths tested, Uhile it is not the intention here to suggest that these tests or the results of the tests should be used at this time to revise our present understanding with regard to the tempera ture limits of serviceability or to indicate changes in the heat-aging tests currently incorporated as a part of several consumer specifications, it would seem that certain parts of the information here developed might well provide engineering data which would be of interest and service to those engineers presently confronted with high temperature materials problems. Conclusions It must be understood that the results here reported are, for the most part, based upon short term tests ranging from a few minutes to two hours, however, one test was conducted for a period of six weeks as indicated. To endeavor to define the limits of the serviceability here being investigated on the basis of the results of these short terra tests would be misleading and ill-advised, however, the data here developed does serve to provide basic information upon which a more thorough and extensive investigation is to be pursued. MT-003640 PRODUCED JM-83 MS 004234 ATI-99 -5We would at this point therefore welcome suggestions from the membership as to the direction to be followed in carrying this investigation further. A clarification as to the temperature ranges of practical interest and the stress or load bearing requirements actually expected would be very helpful in determining the ranges to be covered in further work. It is realised that long term tests will eventually be necessary in order to complete the picture here being developed, however, such tests are time consuming and the results are accumulated very slowly. It would therefore seem desireable at this point to continue to conduct accelerated tests within the limits of practicability in order to definitely define all of the parameters for the full scope of the useful information to be obtained from this work before engaging in the long term tests. O MS 004235 r' MT-003641 PRODUCED JM -83 ATI-99 l.K.'in;.' of .on oral i.c^Ling of tie Asses tts^P.r.tiie I ns ti tube neEr. n; attehiahci: . F. J. V.'aker, President johrs-halville ci?.?. A1HPJCA11 ASBESTOS TEXTILE COR?. J.-Vi. V/eber ASTEiJ-HILL HAHLFACTUHIrG CO. D, >?.. +iolmes jc!iiiS-ii/crvnis con?. U. C. Seeds E. A. Schuman K. Q. Bevard E. H. V.'ells li. S, Hough H. II. Jackson SOU.HLnH ASBESTOS CO, J. T. Griffis G, J. Harris P.. S. Hulsc CASSIA?. ASBESTOS COP.FGP.ATIC::, LIE. T. T. Tigert CAEWAIAOER, V.TCHEESHA:: L TAFT H. I. Rucdcck ASBESTOS TIE'! TILE I SB 71 TUTS ... 0. Sr.a-.; XEASBEI : IIATTISOII CO, C. R. Frederick R. L. Lana A. E. Whitfield D. W. Uidmayer RAYBESTOS-HAHHATTATI, IMC. J. A, 3ettc3 J, A. Brown H. V.'. Oliver F.. 3.. Smith Quests: ASEESTOS TEXTILE CO! FALL Frank Gatkc CARLOOH FAC/.I.'.G CCTPAHY G, E. Houghton . 1. Too r.ee ting was called to order by President Laker, and an address of :: el core extended to all of the members present. Recognition and volcano was also extended to representatives of t:;o former r.er.ber companies v;ho attended the meeting of the Air Hygiene Committee held I larch 7 and '.:cre also in attendance at this meeting, namely. Hr. G, E. Houghton, Oarlock Parting Company, and Hr. Frank Gatke, Asbestos Textile Company, " 2. The Hinutes of the last meeting of the Institute v;ere presented for reeding, however, since all members had received copies of these minutes and v;ere familiar with the actions there taker., it was r.oved by J, A. Bettes, seconded by D, R. Holmes and unanimously agreed that the reading of the minutes oe omitted at this time, ^ 3. The Treasurer's report was read by the Secretary in the absence of J. G. Schcepf, Treasurer, Following a discussion of the contents of this report, it was moved by B. w. Viidmayer, seconded by J. A, Bettes and unanimously agreed that the report be accepted, li. The Secretary announced that the next General meeting of the Institute would be held at Thetford ilines, Canada, on June 6 and 7, and that the necessary ar rangements for accommodation at Thetford and travel facilities to and from the MS 004236 MT-003642 ATI-99 meeting were bcini; by the President and Cecretn.^r As sees, as tne Secretary can neeertain tiie number cf members v;ho will attend inis nee',e eg, this information vrf.ll be turned over +o President baker. ;;ho v.uli ir. turn endeavor to carry the plans forward with some assistance of tiie traffic de partment at Joims-iianvillc Corp, Since it ia unlikely that the full membership ',.111 be nfclo tc attend these neetinge, it is nou planned to hold tlio committee ncetinga normally held on the day preceding the General meeting in Me./ York on the day pro ceeding the Thetford meetings. The results'of ar.y actions token as the ccre mittee meetings v;ill be reported at the Thetford Meetings by the Chairman of the respective committees. The next report was presented by D, R. Holmes, Chairman of the Air Hygiene Committee. The considerations of this committee in session or. ilarch 7 were fully discussed ar.d the specific actions there taken were noted. The comments of Dr. Smith, Johns-!ianville Corp., related to the report issued by Dr. keeper on a subject relating asbestosis with lung and heart diseases was discussed at great length. This latter matter earlier received attention by the Board of Governors and it was announced that this body had appropriated sufficient funds to initiate a preliminary survey to investigate the possibility of more concerted action designed to refute the work of Dr. huetcr. The full report for this committee is attached as a part of the minutes of this meeting. The Sale3 Promotion Committee report was presented by J. ?. Griffis, Chairman. It was reported that this committee has been actively engaged in efforts de signed to promote tho dissemination of information designed to enlighten and educate the conouncr of asbestos textile products regarding their unique characteristics and applications. Tho placement of Visual Aid Displays ar.d plans for the development of the new asbestos textile exhibit were fully discussed. In an effort to speed up tho development of the new exhibit it was agreed that a part of the necessary funds for its construction should bo made available at this time. It vias moved by D, VJ, Uidm.aver, seconded by D. R. Holmes and unanimously agreed that a sura of IrOOG.OO be transferred from the General fund !: y ii t p i t e MS 004237 MT-003643