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More TECHNICAL BRIEFS. were added ofid three new hoi teolite unit* were mounted over ihe filter* to save space. Improved results obtained:-- (1) Alkalinity and COt in steam cut in hall. (2) Phosphate deposits in econ omizer and heaters eliminated. (3) Operating cost reduced from $7.86 to *4,30 per 1,000,000 lb. (4) Total solids reduced 169b and boiler blowoff reduced 25%. (5) Operating control simplified by eliminating soda ash and other chemicals by odding phosphate direct to .boilers. ASME Paper No. S2-A-96. Contamination of Condensate by Hoat Exchanger Tube Alloy*. By J D Ris troph, Virginio Electric A Power Co and E B Powell, Stone A ITebster Engrg Corp. A The accumulation of foreign metal and metallic oxides on the internal heat ing surfaces of high pressure boilers hts become a source of growing con cern to the steam power industry in the United Slates. Especially over the past ten years with the advent of the 2,000 psi and higher pressure, steam genera tors, such deposits hsvo been found serious hazards. These deposits all re tard heat transfer and so tend to pro duce a high temperature in the tube walls, leading in turn to overheating or corrosion or both. Deposits of copper origin seem to have the further objec tionable property of masking the evolu tion of hydrogen from the affected surface, which might otherwise give ad vance warning of the impending failure. Operating experience has pointed to cor rosion and solution of metola of tho iteom-condensate-feed-water part of tho system, external to (he boiler proper, as normally the major source of the boiler heating surface metallic deposits in the so-called 100%-condensate-feedwater type plant to which the present paper directly refers. Virginia Electric and Power Com pany decided to investigate heat ex changer tube alloys as potential sources of metallic contamination of' conden sate flowing in contact with them. The lest equipment employed steam conden sate as actually produced in the power plant and otherwise followed conditions of norma! operation. In addition, it was used to investigate the influence of auch special chemicals as might promise re duction In corrmion and solution of piping end other parts of the steam- condensate system. Results are presented from conden sate contamination studies conducted at two steam power stations to evaluate the Influence ol temperature ol condensate, ol differing dissolved gas content, and of cumulative service time upon iho degree of metallic contamination to be ezpecied in steam condensate of the gen eral character described from flowing contact with tubing of twelve alloys commercially used in power plont beat exchangers. Tho Influence of cyclohexyl* amine on the rates of contamination Is also indicated. The testing procedures are briefly described. ASME Paper No. S2-A-63. Protection of Heat Exchanger Channels and Covers from Salt Water Corrosion. By Wilfred / Dantiger, Olof A Sundholm, M W Kellogg Co. In the usual shell-and-tube Heal ex changer used a a cooler or condenser with fresh water as coolant, the channel, the channel cover, sod the floating-headcover are made of ateel or cast iron. When salt water serves as a coolant, the normal corrosion of ateel and cast Iron by salt water is accentuated by tho golvanlc cell set up by the combination of non-ferrous tubes and tube sheeta with the ferrous materials under discus sion. Ropid failure of the ferrous parts results. This paper describes some of the materials and methods used In pe troleum 'refineries to obtain reasonable life for chonnels, channel covers, and floating heads when using sell water, together with information on perform ance where obtainable. There arc, unfortunately, no stand ard compositions of "fresh," "brackish," TO OBTAIN COMPLETE TEXT Material for these abstracts comes from the following sources unless otherwise stated. Order complete paper from source, not Power. American Society of Mechani cal Engineers, annual meeting, Stetler Hotel, New York, N. Y. Non 30-Dec S. 1952. Identified by initials ASME and obtainable through ASME, 29 W 39th St. New York 18. N. Y. American Institute of Electrical Engineers, winter general meet ing, Statler Hotel, New York, N. Y. Jen 19-23. 1953. Identified by initials AIEE and obtainable through AIEE, 33 W 39th St, New York 18, N. Y. or -Mil" waters, so that focal can have a considerable eflect formance. 0 Within these limitation,, b , that east iron or ateel channels and in, cocr. i,, (,Mh have a probable fife of foQr mr| requiring ony significant maintenance, and 10 to 15 life U not uncommon. In salt woter service, j, _ factory. One refinery reports that channels require repairs in 8 months; onoiher that they umsll within three or four months. A' reports that "salt water attack oa protected steel is extremely rapf we do not use it in these serried cept as a stop-gap measure." TV of cast iron also seems to vary e. erably with local conditions of ih' water, as evidenced by these jud at varied geography: failure imjd two years; failure ol channels months, of floating covers In 9 m life of 6 to 10 months, no better sion resistance than ateel. Although iron appears, in oorae cases, ta more resistance to corrosion than steel coo be fairly easily repsiicd welding and any corrosion is vita, evident. Corrosion of cast Iron lei~ weak, porous, graphitic structure; that extent of damage cannot be lermined by visual Inspection. Drackish .water Is generaOy fnenr the mouth of slowly-flowing The salt content varies with the and, for a particular river, with varying-flow resulting from raia or; spells. With tow salt concentrations low water temperature, corrosioa of end cast iron lo olow; ot higher corrosion approaches that of sea * Thus, it hai been reported that tho, iron channels of four condensers* stalled In 1926 in Harrison, N. J-, cooled with Passaic River water no trouble for several years. Ttio Ing of Wsnoque Dora In the headws of the river and diversion of some* the impounded water resulted In (ides encroaching further up*tf: By 1930 the river water at the to*11 lion was brackish. A year later ? of ibo channels were found to ho corroded, ond corrosion continued o corrective measures were undert** The reported average salt cono*n,n. was 304 groins per gel in appro**081 the last 6 months of 1933; I* I** per gal in the following *. period; and S2S grains per goj *D. gust and September ol 1934. *or {Continued on page 210) 1*4 REAPER SERVICE SECTION Easier, faster, safer with minghouse horizontal ^remove breakers, inspect them, and replace gjya few minutes when you use Westi nghouse 1 Metal-Clad Switchgear. Because breakers wei out horizontally, no lowering or lifting gry. A shutter indicator, visible from the Jgrides positive indication of disconnect postgd>e breaker is withdrawn, a grounded metal Closes to isolate stationary contacts, gtbc breaker is removed, interphase barrier jichutes remove easily to expose contacts at aMble and convenient working height for JppeetioB. the breaker is fust as easy and safe. A jJWTM of a crank move the breaker from dis connect to operating position. A mechanical interlock positively prevents engagement of crank linkage un less the breaker is open. For complete information on Westinghouse Metal- Clad Switchgear for indoor or outdoor service write for Booklet B-5306. Address: Westinghouse Electric Corporation, P. O- Bo* 868, Pittsburgh 30, Penno. r J-MTSS 159