Document 4gGNgDx0rZMNv65kyaxdw7oG

FILE NAME: Power Generation (POW) DATE: 1950 Sept DOC#: POW014 DOCUMENT DESCRIPTION: Published Article from Trade Journal ;t 1950 f f K h k f i I ;: I- [ l !; ;.; f L . : . L . ; L p i P W SWAIN Editor L N ROWLEY F A AN NETT J C McCABE B G A SKROTZKI ExecutiveEditor AssociateEditor AssociateEditor AssociateEditor T G HICKS J J O'CONNOR C F SANDERS C F MARSCHALEK AssistantEditor Assistant Editor AssistantEditor A rtEditor SHELTON FISHER Published W J HARING Sales Manager Washington: GEORGE B BRYANT JR Atlanta: EARLE MAULDIN WORLD NEWS OFFICES: London, Paris, franklurt. Tokyo. Melbourne. Rio de Janeiro. Mexico City SEPTEMBER 1950 VOL 94 NO. 9 PLANT OPERATING METHODS. , ~ ' V ~ ~- r* STEAM GENERATION, FUELS, FIRING AND COMBUSTION TURBINES, ENGINES, AUXILIARIES; HYDRO POWER DIESELS, GAS ENGINES AND ACCESSORIES AIR CONDITIONING AND REFRIGE! ELECTRICAL EQUIPMENT, ELEVATORS PIPING, VALVES AND SPECIALTIES TRANSMISSION, LUBRICATION P J STEAM SERVICES, HEATING INSTRUMENTS, CONTROLS PUMPS, COMPRESSORS i s ! ,-i pp m Solve slagging problems to burn hog fuel efficiently....................................... 74 G o o d wearing rings make good centrifugal pumps............................................ 79 Master T V antennas -- up-to-the minute answers to your questions............ 82 Insulation handbook-- 5: H ow to apply mineral w o o l................................... 86 Sizing your refrigerant lines for minimum-cost operation 91 Leon Creek -- low-cost semi-outdoor station...................................................... 94 Diesel instruments and controls - - 2: Exhaust and intake 98 Shunt capacitors -- where to put them for best results......................................102 Unit heaters show their v ersatility........................................................................... 105 Letters from a turbine specialist -- 1 4 ....................................................................109 Standby diesel engine pays for itself in 5 minutes.............................................110 Refrigerating 15 million cu ft in giant Dallas warehouse.........................................112 H ow stray fields caused lubrication-system corrosion........................................116 Pointers on lube-oil viscosity for anti-friction bearings..................................... 117 H ow does your station stack up with average perform ance?..........................118 Vv fe'.-1 fr!: S :..Y. i; t 1. :4 -r.\ : ' i - h A l .4 A < r4 \4 4 4 'V '-j h '4 l-M 4 ;4l I ` Electronics: Combustion safeguards -- 2 ................................................................ 120 Power engineer's notebook of plant-tested id eas...............................................124 Problems fresh from the plant -- can you answer th em ?.................................. 128 Technical briefs for busy power m en.......................................................................132 Plant equipment news: products and methods......................................................142 Power new s.....................................1 36 G eorge Edwards............................150 Data sheet....................... ............140 Reader's, service page . . . . . . .190a 4 4 4 4 4 ;4 44 4A 4 : 4~:i : 4 . ! 14 h-i ' 4 1 I 4 4T : Li .4 ] 4 i :- 4 j k . l j !L l j jjfej * 4 i 4 ; 4: 4 i 4 : 4 : ' :i 4 4: AS/Mi 'I Ai VOLUME 94, NUMBER 9 ABC ABP COPYRIGHT 1950 by McGRAW-HILL PUBLISHING CO.. INC. ALL RIGHTS RESERVED President and Bond, Vice- Quarles; OFFICE: Hill New y r5r ? 520 N Michigan Ave, Chicago 11; 8 Post S, San Francisco; National Press Bldg, Washington 4; Architects Bldg, Philadelphia 3; 738-9 Oliver Bldg, Pittsburgh 22; 1510 Hanna Bldg, Cleveland 15; 2980 Penobscot Bldg, Detroit 26; Continental Bldg, St. Louis 8; 1427 Statler Bldg, RBaocsLtoana I1X6.; m10i1l1 RD hL aoJdaeas-UHmavu ae.rMty, DBlUdgn , AA tLllannn Ltan 37 ;. t11i l1l1 UW/iIlUshLirI .e. DBlIv. .dJ , Lo__sA _A__n__gIeles %1-7 ; F.irst. . N. .at. ional _Bank Bldg, D a lla s` l ; Aldwych H ouse, A. .ld. wych. London WC2 POWER articles are indexed in both the Industrial Arts and the Engineering Index POWER issues its own index annually; copies are available on request to the editorial offices, 330 W 42nd St, New York 18. P O W E R September 1950 69 Insulation Handbook: Part 5 How To Apply Mineral Wool Heat Insulation -- By PHIL SWAIN, Editor Channels BETWEEN MASONRY WALLS { I'se flat metal ties like those for build ing construction. Walls support insula tion. Ties help hold mason rjttogether Firebrick {BETW EEN METAL SHEETS , Fasten outer and inner sheets to struc tural channels or I-beams. Support insulation from below BLANNET, WIRE-IMPALED { Spot-weld wires to heated metal sur face. Impale insulation and bend wires over its face. Lace edges of blankets together with galvanized wire {C U P-AN G LE SUPPORTS Blanket held in place by metal mesh wired to clip angles at suitable inter vals. Lacing wire joins abutting edges Hot metal STUD-GUN WELDED { Insulation attached by studs inserted through it and'welded to metal surface behind by gun-type equipment Note: In all the drawings shown here MW stands for mineral wool. 86 P O W E R September 1950 Practical know-how for all types of power equipment. Draw ings and condensed instructions summarize standard procedures in U S Dept of Commerce Commercial Standard C 5 l l 7-49, Mineral Wool Insulation For Heated Industrial Equipment, 2nd Ed, 1949 FOUR SUPPORTS Bolt Heads welded to metal surface, upper left. Large washer increases hear ing area on insulation Sheet-Metal Screw and washer hold in sulation in place on heated metal sur face, lower left Bolts Through Drilled Holes n heated surface hold insulation. Washer gives larger bearing area, upper right Hairpin Wires and metal mesh, lower right. Wires pass through twin holes in heated surface and insulation. Twist together to hold blanket in place 4 NAIL FASTENING, MASONRY WALLS Drive masonry nails into joints and fasten hairpin wires to nail heads. Apply blanket insulation with metal-lath face exposed. Secure with hairpin wires. Tightly butt blanket edges and lace together or tie at frequent intervals with 16-gage galvanized wire Loose wool filf Line o f cleavage Hot metal EXPANSION JOINT, LARGE METAL VESSEL} Use every 12 to 16 it on equipment with temperature greater than 600 F. Leave V/2- to 2-in. space between rows of blanket. First apply a ^ -in . coat of insulating cement, then a 4-in.-wide strip of asphaltic mastic over cement just below space between blankets. When dry, fill space with loose mineral wool. Then apply second coat of cement over all except loose wool and mastic. Stretch 20-gage 1-in. wire mesh over cement and secure in place. Do not cover expansion-joint space. Cover mastic strip first with rosin-sized paper and then both expansion joint and paper strip with 1%-in. mesh hardware cloth. Lace cloth to mesh, leaving bottom free to move with expansion and contraction. Cover entire vessel with weatherproof mastic leaving a line of cleavage at lower edge of each cloth. Metal-band protector may be added over expansion joint Metal band Mastic 1 Hardware doth , Wire mesh , LRosin-sized paper MW <-Mastic LInsulating cement P O W E R September 1950 For more insulation fa cts, turn p a g e -->- HANDBOOK: PART 5 Continued CEMENT ON BRICK WALL Drive masonry nails into joints on about 12-in. centers, heads projecting about % in. Apply layer of insulating cement until proper thickness is obtained. Ap ply wire netting and secure to nails before last layer of insulating cement. Then apply cement or asphaltic finish MW blocks Corner bead '(wired on) FLAT SURFACES | (a) shows application where insulation thickness is greater than stiffener height (b) is detail of a corner bead let applying insulation when thickness equal or is less than stiffener height FURNACE WALLS (b) (c) With each wall self-supporting merely lay in blocks or boards, staggering the joints. Butt tightly 9 -gage galv wire on 4 - f t centers \ Hot metal '\\\ j or -in. galv bands on 8 - in. centers BLANKET ON TANK: 1 With evpanded-lath side exposed, se cure blanket to supports. Butt edges tightly, then lace together or tie at fre quent intervals along the edges with 16-gage galvanized wire. Lastly, band or wire circumferentially BLANKET ON TANK: 2 Bound surface makes it easy to bind blanket insulation firmly to the metal. Blanket i< held by wire girdles, lacing, netting and bands Lace blanket edges with 16-gage galv wire Cleaned bare metal surface Insul cement rough spotted by hand \ Galv netting ' Finish cement 88 BLOCK, BOARO ON TANK Butt blocks or boards closely together with joints staggered. Anchor blocks. Then fill voids with insulating cement. Stretch galvanized-wire netting over blocks and apply insulating cement. Stretch second layer of netting and finish with cement or asphaltic CEMENT ON TANK Spot first %-in. layer by hand, roughing in completely. When dry, apply single layers, %-in. thick or less. Use netting for total thickness over 2 in., tanks which vibrate, or on under sides P O W E R September 1950 BLANKET ON PIPE ^ Korin insulation roughly to fit pipe before applying. Put on pipe and pull longitudinal edges tightly together. Tie or lace with 16-gage galvanized soft-iron wire. Keep seam on lower side of pipe. Space insulation far enough from flanges to allow bolt removal. Apply insulating cement and finish BLANKET ON PIPE.FITTINGS I Valves, flanges and fittings for pipes 2-in. and larger should be insulated with blankets the same thickness as on adjacent piping. This insulation is applied after that on pipe. It is formed to fit by cutting, wired in place. I.ace the edges. In sulating cement or blocks may be used instead of blankets ,MW blanket Insulating cement Asphaltic or other finish INSOLATING CEMENT ON FITTINGS | First coat of sufficient thickness must dry and form an even base for two separate Vi-in. finishing layers. Pipes, valves, flanges and fittings may be finished with roofing-felt, an asphaltic coating or a canvas jacket. Roofing-felt is held in place with copper-clad steel wires, copper wires or galvanized bands. Asphaltic finish is reinforced by gahanized-nirc net ting. Canvas jackets must be sewn or pasted over a layer of flame-proof asbestos paper or a Vi-in. coat of insulating or finishing cement SECTIONAL PIPE COVERING } Single Layer, upper sketch, is applied by butting sections closely and banding canvas jacket or other finish over insu lation. Insulation must be kept far enough from flange to permit bolt removal Double Layer, lower sketch, is applied by wiring first layer in place with separate loops spaced on about 8-in. centers. Omit canvas jacket between layers. Second layer is banded in place over first, using canvas jacket or other finish. Never leave any sharp projections on bands. Thev may cut finish Sectional insulation Canvas jacket or other f i n i s h M e t a ! band SEGMENTAL PIPE COVERING | To get a good job, butt segments tightly before wiring in place with 16-gage galvanized wire spaced on about 8-in. centers. Use insulating cement in joints where needed. Bend over ends .of wires and press into insulation. Finish with canvas jacket or other material and band with metal P O W E R September 1950 For more insulation facts, turn p a g e - y HANDBOOK: PART 5 Continued MOLDED-TYPE FOR COUPLINGS You can use molded-type pipe insulation to insulate flanged couplings. Wire rings of sectional pipe covering 1% to 2 in. wide on each side of the flange. Rings should have an OD greater than flange diameter. Band a piece of sectional pipe insulation in place over flange and rings. Finish with insulat ing cement or other material For large fillings use blocks (hat are h i in. less thick than the insulation on the adjacent, piping. Fit carefully and wire securely in place with 16-gage galvanized wire. Then apply 14-in. coat of insulating cement over blocks, troweling it well into all cracks between adjacent blocks. Other specified finishes may be used in place of insulating cement Facts to Remember About Mineral Wool Mineral wool is rock, slag or glass processed from molten to fibrous form. It is used in loose, granulated, felt, blanket, batt, block, board, molded and blanket (for pipes) form. Insulating cement is a dry mixture of mineral wool and other ingredients which when mixed with water can be troweled. Commercial mineral wool is classed according to maximum temperature limits as: Class Temperature, F A 600 B 1000 C 1200 1600 1800 The K Factor The K value (Btu transmitted per hr per sq ft for a temperature gradient of 1 deg F per inch of thickness) varies from a low of 0.35 for batts at 200-F mean temperature to a high of 0.80 for insulating cement at a mean tempera ture of 400 F. Other forms fall in be tween these values. Density and physical properties depend on form and intended use. For low temperatures K doesn't exceed value of 0.28 at 50-F mean temperature. Minimum thicknesses recommended for refrigerated spaces vary from 3 to 4 in. at 35 F to 12 in. or more at -1 0 F and below--Commercial Standard CS105-48. Pipe Insulation Molded-type pipe insulation comes in 1, 1%, 2, 2%, 3 and 4-in. thicknesses for all nominal pipe sizes. It is also available in "standard" and "double standard" thicknesses, table below: Insulation Thickness: Standard (S) And Double Standard (DS) Pipe size, nominal 1 /2 to 1 1 /2 2 to 3 1 /2 4 to 6 8 & 10 v . 12 and over S 7/8 1 1/32 11/8 11/4 1 1/2 DS 1 3 /4 21/16 2 1 /4 2 1 /2 3 Flat-Surface Insulations Loose or granulated mineral wool for use at temperatures up to 1600 F is packaged in bags containing up to 40 lb each. Felts suitable for use up to 600 F come in sizes 1 to 4 in. thick x 24 in-. - wide, 30 or 48 in. long. Blankets suitable up to 1200 F come in 1 to 6-in. thicknesses x 24 in. wide, 4 or 8 ft long. Industrial batts usable up to 1200 F are 1 to 4 in. thick x 24 in. wide, 4 ft long. Blocks are 1 to 4 in. thick x 6 or 12 in. wide, 18 or 36 in. long. 1 to 3-in.thick boards, 12 to 36 in. wide, 3 or 4 ft long, are also standard. These blocks and boards can be used at temperatures up to 1200 F, according to class. Insulating cement can be used at any temperature up to 1800 F. It is pack aged in 50 lb bags. Minimum coverage is 45 sq ft, 1 in. thick, per 100 lb of dry cement. Application Here are a few characteristics im portant in using mineral wool: Loose, Granulated and Batt Wool: Low in cost but need structural retention and protective finish such as a metal shell or masonry. Felts and Blankets: Low in cost, good thermal value with some rigidity. Not designed for load-bearing service. Blocks and Boards: Rigid with good compressive strength. Can be installed where operators may have to cross in sulation for maintenance, etc. Blanket-Type Pipe Insulation: Flexible with good thermal properties. M olded-Type P ipe Insulation: Rigid and strong, it is easy to install. Insulating Cement: Good adhesive prop erties and easy to spread over valves and fittings. It can be re-used. 90 P O W E R September 1950 i' wW a k p. y | V : ' f > s - m m Eag le-P icher Insulation can help you get maximum heat and pow er from each fuel dollar expended Here's insulation t that will save you money EAGLE-PICHER DE-85 BLOCKS \ A highly efficient, rigid-type insulating ma terial composed almost entirely of pure, light weightHEaglc- Picher Diatomaceous Earth. High physical strength enables these blocks to stand up under usage normally encountered in installation. Adaptable to virtually all types of heated equipment. Can be cut with a knife, or sawed, to fit irregular shapes. DE-85 Blocks for temperatures to 1300F. DE-95 Blocks for temperatures to 2000F. EAGLE-PICHER " 9 9 " FIN ISHIN G CEMENT Finishing cement for temperatures up to 1000F. Adheres tightly to hot or cold surfaces with practically no shrinkage. Highly durable. Gives a smooth, hard, light-colored, paintable surface. i EAGLE-PICHER STALASTIC (Boiler Wall Coating) E ffectively seals against air infiltration through boiler settings-- seals cracks and pores, effects substantial fuel savings. Great adhesive strength, retains its elasticity. For temperatures up to 400F. P O W E R September 1950 An Eagle-Picher Industrial Insulation distributor or representative can help you reduce operating expenses because he has available a wide line of insulation products-- for high and low temperatures-- scientifically designed for maximum thermal efficiency, and practical application. Why not let him give you more information about some of the products listed here? These Eagle-Picher products can save you money. . . power. . . time Insulating Felts Supertemp Blocks* Blankets Loose Wool Pipe Covering Stalastic Insulseal Insulstic Swetchek Finishing Cements Insulating Cements Fireproofing Cement Diatomaceous Earth Blocks TE EA G LE-PICKER COMPANY EAGLE General Offices: Cincinnati (1), Ohio Insulation products o fefficient mineral wool--fo r a fu ll range o f high and low temperatures. Technical data on request. P IC H E R 2100-2101 Since 1843 1 trt