1254
INDUSTRIAL AND ENGINEERING CHEMISTRY
Ilurst, J. E., and Riley, R. V..Iron and Steel (Londori), 17, No. 10, 425 (1944). (SA) Ibid., 18, No. 8, 333 (1945). (9-4) H u r x , J. E., and Riley, R. V., J. Iron Steel Inst. (London) 149, I, 213 (1944). (10-1)Itid.. 149, I, 221 (1944). (11-4) Hurst, J. E., and Riley, R. V., Ifetallurgin, 29, No. 171, 14.5 (1944). (12d\ Ibid.. 29, No. 171, 427 (1944). !13A) Klinov, I. Y., Trudy Konfuents. Korrozii Metal., 2, 216 (1943). ‘:4 i) Liang, Hung, Bever, 51. B., and Floe, C. r.,Metals Technol.. 13, No. 2, TP S o 1975 (1946). ls>.i1 Lipson, H., and Weill, A. R., Tranu. Faradau Soc., 39, 13 (1943). (1ti.i’ Rcavell. B. N.. Chem. Age (London). 42. S o . 1088. 19 (1940) 11iA>.i Vaughn, J. C., Jr., and Chipman, J., Trans. -4m. Inst. J T i u i n g Met. Engrs., 140, 224-32 (1940). ( t a l l Ward. R., Ibid., 152, 141-55 (1945). ( 1 Q - 1 j Weill, A . R., Nature, 152, 3853 (1943). t20-Y) ‘Xei!l, A. R., Rev. mdt , 42, No. 8 , 2G6 (1945). (214) IT’razej, W. J., J. Iron Steel Inst. (London), i49, I, 227 (19.11). ‘ 2 2 \ 1 Zappfe, C. A , , and Clogg, >I., Jr , T?ans.Am. So,-. IlTetds 34, 71-107 (1945). < I!.:
(9Bj (10B) (11B) (12B) (13B) (14B) (15I3) (lGB) (17B) (ME)
(19R) (?OB)
4
AUSTENITIC CAST IRONS
lB) Anonymous, Inst. Mech. Engrs. (London), J . , 143, 218 (1940) (2B) Ibid., 147, 88 (1942). (3B) Ibid., 149, 101 (1943). 4B) Ibid., 149, 103 (1943). ,5H) -4ustin, H. S.,Metal Proy:ess, 39, 097 (1941). (6B) Bollon, L. W., J . Iron Steel Inst. (London), 144, 89 (1941,. (7B) Bradley, A. J., and Goldschmidt, H. J., Ibid., 140, 11 (1939). M 3 ) Eash, J. T., Trans. A m . Fovndr!jmen’s Assoc., 49, 887 (1942)
(21B) (22B)
Vol. 39, No. 10
Ibid., 50, 815 (1913).
Galibouiy and Laurent, P., Compt. rend., 209, 105 (1939). Klinov, I. Y., Khim. Referat. Zhur., 4, No, 4, 140 (1941). Klinov, I. Y., Org. Chem. Ind. (U.S.S.R.), 7, 173 (1940). Le Thomas, A,, Rev. nickel, 10, 98 (1939). Morton, B. B., Petroleum Engr., 13, No. 8 , 13@ (1942). Owen, E. A., and Sully, A. H., Phil. Mag., 31, 314 (1941). Pcarcc, J. G., Chern. Aye (London), 45, 69 (1941). Penrce, J. G , , F’oitndry TradeJ., 65, No. 1305,121; No. 13i)G, 139: KO. 1307. 158 (1941). Peaice, J. G., Inst. Jfech. Engrs. (London), J . , 140, 163 (1938). ILid , 146, 61 (1941). dsclis, G., and Spietnak, J. W., Trans. A m . Inst. M i n i n g .Ifel Engrs., 140, 359 (1940). Sefing, F. G., and Nemser, I). A ,Product Eng., 16, 799 (194,5) Sefing. F. G., Ibid., 17, 92 (1946). AUSTENITIC MANGANESE STEEL
(1C) bnonyinous, Iron Age, 146, 40 (Oct. 17, 1940). (!E) De Boncly, J. A , , Can. Metals M e t . Inds., 2, 279 (1939). (:G) Farlow, V. It., and McCreery, L. EI., X e t a l s Alloys, 14, KO.5 , 692 (1941). (4r)Franks, It., Binder, TT. O., and Brown, C. X f . , Iron Age, 150 S o . 14. 51 (1942).
( 3 2 ) Goss, N. P., Trms.’ A m . SOC.Metals, 34, 630 (1945). i6C) Niconoff, I).Ibid., . 29, 519 (1941). (7C) Ibid., 31, 716 (1943). (8C) Rice, D. B., Iron Age, 146, 33 (Oct. 31, 1940). (9C) Uhlig, H. H., Trans. A m . Inst. Mining M e t . Engrs., 158, 183 (1944). (1OC) Walters, F.M., Jr , Kramer, J. R., and Loring, B. RI., Ibid., 150, 401 (1942). (11C‘) Young, L. P.. and Goard. D. H., Can. Mining M e t . Bull.. KO. 372,170 (1948).
Chemical Stoneware F. E. HERSTEIN, General Ceramics and Steatite Corporation, Keasbey, N. J . ERAblIC materials are among the oldest known to nian, and it may be said that the progress of a civilizat,ion can be measured by its ceramic technology. A history of the ceraniic industry in general is given by Singer (22). Chemical stoneware in Its present form is a relatively new material t,o this industry, and its historj-, starting with the first stoneware factories in England in the early part of the ninetcrnth century and continuing t o its inccption in this country and continued use and progress, is described in an article by Kingsbury ( 1 2 ) . r l r n e manufacture of chemical stoneware follows the general pattwn for all ceramic materials. The raw materials are mined. wished, prepared by deaeration, stored for a n aging period, fabricated by jiggering, casting, molding, extrusion, or turning on t t x potter’s wheel, dricd, fired, and t,hen prepnred for final u.ce in most cases by grinding to the dimensions requircd or assembling n-ith other equipment. Olive gives a flow sheet shon-ing the manufacture of chemical stoneware (17) and a description of :nanufacturing techniques in a domestic factory (16). Singer also describcs manufacture and defines chemical stoneware (bS), and British pract,ices are discussed by Hodson ( 7 ) . In considering chemical stoneFyare as a material of chemical [:onstruetion, it is neccssary to evaluate its advantages agdilst its limitations. Chamberlain states its main advantage t o be its i,esista.ncet o corrosion by all acids rxcept hydroflucric and strong hot caustic. Except for these two, it may be called universally corrosion-proof. It is also a comparatively inexpensive material, and, because of methods of manufacture, special shapes in sniall (limntities can be made at a fairly economical cost. Its main clisadvantage is its relative fragility, which is shared by all ceI amic materials. I n application, its st,ructural qualities, such as
very high compressive strength and low tensile strength, are taken into account in the design in order that tensile stress and mechanical shock are avoided. Although the term “chemical stoneware” is generally consideied to cover one type of material, it is really a generic term for a w a m i c body with a high density, low porosity, and high perwntagc of vitrification. Since the uses to which this material is put vsry, properties that arc desirable for one application may be undcsirable in another, and most stoneware manufacturcrs Foiinulate various bodies for different uses. An illustration of thiq 19 the use of silicon carbide bodies for applications both involving thermal shock and requiring enhanced thermal conductivity. It has been found that these bodies have a thermal L*oriductivit>-thiee to four times greater than standard stoneware, .I discbssion of various types of bodies and heat shock resistiiig bodies in particular is found in an article b y Robitschek (21) A discussion is also given by Kingsbury (12). Besides thew bodies other types such as extremely dense bodies for electrolytic service (IS), heat resistant bodies for chlorine service ( 6 ) , and porous bodies for use as diaphragms in electrolytic processes (25) have also been developed. A description of the bodies maiiiifactured by one company is given in a company bulletin
(4). To obviate the main disadvantages of chemical htonem are-n a i n e l ~, fragility and resistance t o thermal shock-research is !wing undertaken by chemical stoneware manufacturers in this country with a view t o developing bodies which will minimize these unfavorable properties and still retain the corrosion resistance which is inherent in chemical stoneware. Some of the research being undm taken non and already completed with this
October 1947
INDUSTRIAL AND ENGINEERING CHEMISTRY
t*
Figure 1. Armored Centrifugal Pump
end in view is described by Knisek (16.1,Kingsbury ( I d ) , aiid Robitschek (20). Most of these improvements have been in the direction of reducing failure due to thermal shock. However, by-products of this research have been bodies which are also mechanically stronger. Failure due to mechanical causes can be eliminated in most cases by designing and installing to diminate tensile stresses and, in extreme cases, armoring thr +quipmerit. APPLICATIONS .4ND USES
dtoneware piping is available in diameters ranging from 1 t,o 24 inches for standard sizes and up to 60 inches in diameter for special sizes. For handling gases and liquids a t IOW pressures, the familiar bell-and-spigot piping is used, although many chlorine plants use butt end-wrapped joint' piping for conveying hot, wet chlorine at low pressures. For higher pressures flanged piping is used, either the conical flange type which is held together by a split metal flange cushioned against the cone at thy end of the pipe or the cemented-on flange pipe which uti!izw a metal flange cemented to the pipe with an acidproof cement. The latter type is becoming more popular; it is lighter because it eliminates the heavy conical flanges and also avoids the wcessity of separate flanges. A discussion of various types of stoneware piping, illustrations, and methods of installation are given by Pryce (18). Stoneware tanks and storage vessels are offered by most manufacturers in capacities ranging from 10 to 700 gallons and in rectangular, cylindrical, and jar shapes. These are used in the plating industry (@, for storage of hydrogen peroxide 119),and in the rayon industry (10). They are also widely used for the manufacture and storage : I / ' hydrochloric acid. Because of its relative fragility, chemical stoneware is sometimes not thought of for mechanical equipment (Figure 1). However, hoth centrifugal pumps and exhausters are manufacturd by domestic and foreign stoneware companies. Both of these items of equipment are usually armored t o prevent mechanical failure. Pumps are available ranging in capacities from 10 to 800 gallons per minute a t heads up to 80 feet. Exhausters with capacitie,. from 50 to 3400 cubic feet per minute a t maximum pressures of 3.6 inches of water are supplied by several domestic companies. Stonemre exhausters capable of higher pressures are also being marketed by at least one European concern. A discussion of >toneware pumps is given by Chamberlain (3). Kingsbury and Mehrof describe stoneware exhausters, with test procedure and characteristic curves (14). Stoneware cooling coils have found wide use in the manufacture of sodium hypochlorite. Heat exchangers for reducing
1255
the temperature of hot, vet chlorine are also widely used in thr chlorine industry. These are described in a recent article hy Herstein (6). stoneware towers for absorption, reaction, and fume removal are used for this purpose probably more than m y other material of construction. For installations involving low pressure, bell and spigot towers are used, and for higher pressure, flanged t.ower.q with cemented-on steel flanges are usually installed. A . type of tower which is almost always constructed of chemical stoneware is t,he cascade tower for drying chlorine with sulfuric acid (6). For reactions requiring stringent corrosion resistance, kettle8 and reactors are available. These are made in capacities up tcJ 360 gallons, and can be equipped with stoneware agitators and covers. They can be heated either externally by immersion iii an oil or hot water jacket or inrertially 0 ~means . of a tantalum coil or fused silica electric heaters. trmoixd reactors for vcrj. stringent' services can also be obtained. The Nutsch filter is a commonly used piece of stonervarc. equipment. These filtepi are made in diameters as large as 35 inches and with t,otal capacities as high as 190 gallons. Pressure filters for pressures up to 30 pounds per square inch are also ohtainable. Porous diaphragnis made of ceramic material are manufa!tured for electrolyt,ic purposes. These are widely used in the nianufacture of hydrogen peroxide; t,heir properties and characteristics are discussed by T'elisek and Vasicek (25). T h k artic:le details the electrical characteristics of such diaphragnis and methods of testing for them. .Z coninion usage for stoneware is in lining equipment whicli is too large to he made in one piece. The linings have the inherent weakness of being no stronger than t,he jointing material iiwd; but, rvit,h t,l:e progress in cements made in the last 20 years, thcy have hecome increasingly popular. . 4 descriptio11 of Iiniii~ techniques dong with cemmts which are applicable is givrri t,\ kings bur^- fll~i.
Figure 2.
S t o t u w are
Tourills
In addition t o the tiluipinciit dewibed, chemical stonewtii 1s used for cocks and valves, acid elevators. laboratory sinks, a&! absorption tourills (Figure 21, and other items of process equipment. A full description of all of this equipment can be found in the catalogs of any of the three stoneware manufacturers in this country (Maurice A. Knight, 1.: S. Stonerrare, and Genrrai Ceramics and Steatite Corporation). IIydrogen peroxide is one of the most corrosive chemiralb handled in modern technology, and chemical stoneware is uied almost exclusively as a material of construction for electrolytic cells, diaphragms, and distillation and condensing tower*. deveral articles describe the utilization of such apparatus in itb manufacture (1, 2). A recent report by the United State>' Office of Technical Services (26) shows pictures and drawingq :I
6256
INDUSTRIAL AND ENGINEERING CHEMISTRY
German hydrogen peroxide plant utilizing thir equipment. Reichert and Pete (19) describe the uses of various materials of sonstruction with hydrogen peroxide. The manufacture of 2hlorine and hydrogen peroxide are electrochemical industi ies. and an article on the use of chemical stoneware in the electro-hemica1 industries in general is reported by Kingsbury (13) Chemical stoneware, besides its use as a material of construction, is utilized in the manufacture and handling of acetic acid (6), in metal plating (8), in the rayon industry ( f O ) , and in .he manufacture of foodstuffs such as vinegar ( 2 7 ) ; it has also wen utilized, although generally only for very large pieces, for +lectrical insulators (24). CompanieG of the pharmaceutical industry, where the slightest contamination is not permissible, are also large wers, as are, l o a limited eutent, the food indiistries The utmost advantage car1 be obtained from chemical stoneware when it is installed and maintained in a manner such ab to minimize its fragility and susceptibility to thermal ihock. Methods of installation for ceramic equipment are rlPsrribPd h> Kingsbury (9, 11) and Pryce (18).
Vol. 39, No. 10
General Ceramics Bulletin, “Properties of Ceramic Bodies for Chemical Stoneware Equipment,” 1946. Herstein, F. E., Chem. Eng., 53,No.12, 214-16 (1946). Ibid., 54,No. 3, 216-20 (1947). Hodson, G. N., PotteTy Gaz., 59,No.679, 65-70 (Jan. 1934,. Hogsboom, G . B., Jr., and Hall, N., ,Metal Finishing, 44,KO.2, 63-6 (Feb. 1946). Kingsbury, P. C., Chem. Inds., 45,564-6 (1939). Kingsburs, P. C.. IND. EPG.CHEM.,22, 130-2 (1930). . . Ibid;, 29,402-5 (1937). Kingsbury. P. C., Trans. Am. Inst. Chem. Enyrs.. 36, No. 3. 433-42 (1940). Kingsbur)., P. C., Trans. Electrochem. Soc., 75,131-9 (1939). Kingsbury, P. C., and Rlehrof, F. E., Am. Inst. Chern Eners., Mtg., Berlin, N. H., June 21-23, 1926. Knisek, J. O., Ceram~icInd.,37, X o . 6, 74-6 (Dec. 1941). Olive. T. R.. Chem. & Met.. 40.369-71 11933). Ihid.. 46, 512-16 (1939). Pryce, -%. C. H., I n d . Chemist, 244-0 (Oct. 1941). Reichert, J. S.. and Pete, R. H., Chsm. Eng., 54,X o . 1.L13-Lb (194ij. Robitschek, J. H., Ceramic A g e , 40,S o . 5, 134-6 [Nov. 1942j. Robitachek, J. H., Ceramic Ind., 41,No. 1, 48-51 (July 1943); 41,So. 3, 64--6 (Sept. 1943). Singer, F., Address before Assoc. of Czechslovak Scientists & Technicians, Communication 119 (Feb. 23, 1944). Singer, F., Ceramic Age, 17, No. 6, 300-5 (June 1931j. Singer, F., Helios Elec. Ezport Trade J., 38,355 (1929). Velisek, J., and Vasicek, A., Kolloid-Z., 1, No.1, 36-48 (19353. Wuldenburg, M., and White, L. M.,C . S. Dept. of Commerce. Office of Pub. Board, R e p t . 197 (June 1945). Wustenfeld, H., Deut. Easigind., 30, No. 17-18, 137, 138. 145 (1926).
L I T E R l T C R E CITED
lr Anonymous, Chimle & industrie, 28, No. 3, 507-23 (1932). !2) Anonymous, Ullman Encyclopedla, 10, 420-34 (1932). 13) Chamberlain, J. hl. W., Machane Derign, 6, S o . 6, 23-5, 80-2 (1934).
WOOD ALFRED J. STARIM, U . S . Forest Products Laboratory, Madison, Wis.
F
RON the beginning of Vorld War I1 UJI to the present time
the supply and demand for wood as a structural material have undergone drastic changes. During the early stages of the war when practically all metals were in short supply, wood was called upon to fill a large part of the gap. I n some cases wood served as an excellent substitute, whereas in others it could be considered only an emergency substitute. This burden on wood as a substitute for so many items, added to the normal evtensive uses where it naturally excels, finally resulted in the demand greatly exceeding the supply. Fortunately, M hen this occurred, the supply of metals was materially improving. The drain on wood has not abated since the end of the war, because military demands have been replaced by domestic housing and industrial structural demands. This cycle of events has been a healthy situation from the standpoint of wood research. The need for modifying wood for special uses was for the first time fully appreciated and resulted in research that has, in a number of instances, already paid dividends. Kood is, in many respects, an ideal structural material. ETcept for the last two years of the T a r and the first postwar year, it has been readily available. It has eytremely high strength per unit weight. It is noncorrosive and has the highest thermal insulating value of the structural materials, and above all it is extremely easy to fabrlcate. Its chief drawbacks are that it is susceptible to decay, it isill burn, and it will shrink and swell. These shortcominA5 can be overcome to an appreciable extent by
PRESERVATIVE TRE4TBIENT
The preservstivc treatment of wood is an old, well developed industry in d u c h there have been no revolutionary advances since the beginning of the Tar. Creosote is still considered the
most effective preservative against decay, termites, arid niariiir borers (40). Preservatives of the so-called clean types, comprising both the inorganic salts, such as chromated zinc chloride (36, 40), and toxic organic compounds dissolved in a clear organic solvent, such as pentachlorophenol (24, 34), have nevertheles~ gained in uqe because they do not discolor or impart an odor t c wood and can be painted over. Background on all phases of the wood preservation indu3try can be obtained from the most up-to-date book on the subject (40). The important features of toxicity and permanence of the preservative, together with the adequacy of the treatment, from the standpoint of amount of preservative taken up, its distribution, and the depth of treatment, should all be considered. Inforniation on specifications is given in two recent publications ( 2 , 96). The special problems of protection against termites (43, 7 1 ) and marine borers (8, 66) are covered in special reports on the subjects. Methods of treating by pressure impregnation and bj steeping are covered in several Forest Products Laboratory reports and Cnited States Department of Agriculture bulletins (14, 38, 39, 4 6 ) . (The former are available from the Forest I’roducts Laboratory on request without cost. The bulletins are available from the Superintendent of Documents, Kashington, D. C., a t slight costs.) An up-to-date general discussion of factors influencing decay and the natural decay resistance of various species has been compiled (36, 40). General reports on available preservatives and testing of preservatlves have been issued (27, 29, 40). T o obtain optimum service life of timbers used outdoors as equipment supports, permanent scaffolding, etc., the material should be creosoted. Slmilar wood structures under roof cover but still subject to decay may be treated with accepted toxicsalts inqtead of creosotes. The service life of wooden pipes, sluices
