Document 2jwJaaqgLEZ8bxxo9B09mmX5L

Red Lead Guards Against Rust On Famous Bridges THE new North State Street Bridge. now nearing completion, is among the prominent landmarks in down town Chicago. This double leaf trun nion bascule bridge will be verv simi lar in appearance to the Wabash Ave nue Bridge which was awarded first prize by the American Institute of Steel Construction as the most beauti ful bridge of its kind, costing over one million dollars, when it was com pleted in 1930. This new- bridge and other bridges built and maintained by the City of Chicago are protected by a priming coat of red lead paint. Although the clear span of 210 feet is 22 feet shorter than the Wabash Avenue Bridge, the greater width ranks it among the largest bridges of its kind. It represents an investment of approximately 3.5 million dollars. More than seven million pounds of structural steel have gone into its building. Each of the movable leaves, shown in raised position in the photo graph on the cover, will weigh about 8,400,000 pounds when completed. The new bridge measures 307% feet from anchor column to anchor column and has a clear span between masonry of 210 feet, overall width of 108 feet with two roadways 36 feet wide, separated by a center island 5 feet wide, and two sidewalks with clear widths of 11 feet each. It has three trusses of the so-called railing height type, the top chord rising above the bridge deck to a height about equal to that of the railings. A factor that contributes greatly to the wearing out of a bridge is the fre quency with which it has to be opened, and this same factor greatly affects the usefulness of the bridge to the public. The old bridge provided 16.5 feet vertical clearance for a width of barely 50 feet at right angles to the general channel, and the truss chords sloped downward sharply from that height almost to water level at the piers. Consequently, it had to be opened frequently and was always in danger of being damaged. The new bridge provides 20 feet vertical clear ance for a width of 100 feet and 16.5 feet clearance for nearly 160 feet: permitting free passage of tugs and barges without opening the bridge and interrupting street traffic. Navi gating conditions are also improved by a change in the channel alignment, which formerly had a pronounced bend at this point. The bridge is designed to carry a continuous line of 50 ton street cars in each direction, a load of 125 lb. per square foot on the roadwavs and 100 lbs. on the sidewalks. It is capa ble of carrying the heaviest vehicles that will be developed for years to come. This up-to-date multi-million dollar structure is protected with a coat of red lead priming paint formulated ac cording to City of Chicago specifica tions. The specifications for this bridge called for a shop coat of red lead and spot painting with red lead after erection. The City of Chicago specification for red lead priming paint contains 77.5% pigment and 22.5% vehicle 2-- -- Painters apply ing one of the tuo red lead un dercoats speritied tor the first re painting of the San FranciscoOakland Bar Bridge shoun at left. W I [)E- u ORLII PtIOTl'S bv weight. The pigment consists of 99.7% red lead i95% gradei and 0.3% aluminum di-stearate. The ve hicle consists of a mixture of 44.2% raw linseed oil. 23.8r< heat treated linseed oil of Z2 Gardner viscosity. 30% mineral spirits and 2.0% drier. The bridge is being constructed under the supervision of O. E. Hew itt. Commissioner of Public Works, W. W. DeBerard. Ci tv Engineer and Stephen J. Michuda. City Bridge and Viaduct Engineer. The reliable red-lead-in-oil type primer formulation used by the De partment of Public Works of the Cil' of Chicago is used by the majority of cities and states throughout the country to protect iron and steel struc tures of all kinds. While Chicago's North State Street Bridge displays its first suit of red armor for warding off the always vi cious dragon rust, the veteran Queensboro Bridge in New York City is hav ing its ornate and complicated canti lever structure redressed with another protective film of rust inhibitive redlead-in-oil and a topcoat of tinted white-lead-in-oil paint. Since rearm- L IA25940 m ing this one-and-a-half mile steel giant against the ravages of an industrial;zeti citv environment is a tremendous ask requiring the application of tiH) gallons of red lead primer to r-tores of painters, it is !ortunate that 'tie paint system has an expected ;>roicclive life of trom eight to ten i ear.'. \nother beauufui and acrid re new n structure protected h) an andet coat of red lead is the dan Francisco. Oakland Bav Bridge. This bridge, the longest on earth, consists of a cornomanon oi a cantilever -- truss -pan and two complete -mspension bridges placed end to end. The total length of the bridge, without approaches, measures Tip miles. The repainting of this bridge with a three coat svstem has been in prog ress for the past eleven rears. When this job is finished it wiil be time to 'tart at! over again. The present re painting includes two coats ot red lead primer. Lead Protects Concrete From Acid Attack PENICILLIN nas become a magic is me of the prominent companies word in medicine since Alexander w men pioneered ;n the commercial Fleming, a British phvsician. first dis manufacture of penicillin. Thev are covered it in the middle of the last currently producing a large propor century. But even this antibiotic with tion of this drug which contributes -o miraculous healing power? couidn t much to man ? protection against di cure an lil that created a serious sease. 'hreat to its manufacture. In the course of penicillin manufac The Hevden Chemical Corporation ture. suifuric acid must be kept avail i Aeer lead pan nstalled under ic;d tanks to tso.ore them t o m : n e concre!e It>or. Th we: scuff are fhe re mit ot periodic :i eftmg Jou n ot :he concrete. able for use in various processes. The acid is diluted and stored at room temperature in two 650-gaL giass- lined tanks from where it is conducted through pipe lines to reaction vessels. Leaks that developed in the conveying Sines and fittings of a material other than lead permitted sulfuric acid to drip onto the concrete floor suppurt- ing the heavy acid-filled vessels. De spite frequent repairs and attempts at neutralizing the acid attack, the concrete continued to deteriorate and weaken. glnce anv leakage of sulfuric acid onto concrete floors is difficult to neu tralize. the engineers at He\ den ( hemical Corporation adopted an in telligent and Simple method of pro tecting their concrete flooring from the corrosive action of the acid. Thev decided to take advantage of the time- tested reputation for sulfuric acid re sistance established b\ the metal, lead, as long ago as 1746 when it w as first used in chambers lor burning ,-ait- peter and brimstone to make sulfuric acid. Thev installed underneath the two acid tanks and their fittings a 3-- LI 4?594i I shallow rectangular lead pan to retain any dripping acid, keeping it away from the concrete. The large lead pan under the acid tanks shown in the illustration con sists of four sections of 12-lb. chemi cal lead burned together to form a continuous sheet TTw ft. wide and IT ft. long. All the seams are lapped 2 in. A bitumastic layer protects the pan from direct contact with the con crete flooring. To make the 4-in. high retaining walls, separate sections of 12-ib. lead were burned on, then turned up and lapped over the upper edge of a 4-in. angle frame in front and on one side. In back and on the other side, the edges are turned up against the walls. .As an added pro tection against vibration, the heavy tanks are supported on eight circles of 24-lb. lead. 14 in. in diameter. The pan is graded to a drain where any acid leaking from the fittings can be washed away. For added rigidity the floor drain is constructed of 4-in. pipe made of 3 per cent antimonial lead. Pipe lines passing through the pan and concrete floor are guarded against splashing and overflowing liquids by a ^-in. soft lead boot or sleeve. 6 in. high and 6 in. inside diameter extending up from the base of the pan. A detail of the lead pan installed under sul phuric acid tanks in the plant ot the Redden Chemical Co. Lead was the obvious choice for this installation because of its ac knowledged resistance to sulfuric acid and its ease of installation and repair as well as for a reason peculiar to lead and its alloys--the high salvage value of the metal itself. The latter property, particularly in the face of rising material costs, is becoming an increasingly more significant factor in the selection of metal for use in chemical construction. Because onlv its shape is altered and not its internal structure or physical characteristics and because it is easily remelted, lead has a salvage or scrap value which usually closely approximates its ori ginal cost. Lead Weatherproofs Fasteners For Corrugated Asbestos Roofing LEAD'S usefulness as a sealing ma pieces under the roof, is inserted terial has long been recognized through a drilled hole from -above and new methods of utilizing this val and turned so that the hook end firmly uable property are constantly being grips the leg of the cross beam purlin. developed. A series of new type fas Then a lead seal and tab cast in one teners for asbestos corrugated roofing piece and a steel washer are slipped was recently developed by the H. & B. on and bolted down. After drawing Enterprise Corp., Trenton, J. They up tight and forcing the lead seal into have licensed the Keasbey and Matti- the recess around the bolt, the excess son Co., manufacturers of asbestos length of bolt is snapped off and the corrugated roofing, to market these remaining end covered w-ith the lead new fasteners under the trade name. tab. In this manner the nut, washer, "Top-Side" Fasteners. and bolt are covered with a protective1 These fasteners eliminate the cus lead sealing cap. The lead seal forms tomary expense and inconvenience of a permanent complete seal for the scaffolding and workmen beneath the hole through the asbestos corrugated roof because the entire installation is sheets while the tab portion provides completed from the outside roof sur a non-corrosive permanent covering face. A threaded steel rod, curved on for the raw- steel broken end of the one end to grip the supporting cross fastener bolt as well as protecting the --4-- nut and washer from atmospheric corrosion. Thus each fastener is per manently weather proofed making the separate step of cementing bolt heads unnecessary. An important consideration with asbestos corrugated roofing is the pro vision of a means for overcoming vibration without violating sound con struction practices. Here again one of lead's unique properties qualifies it. The springing action of the fastener coupled with lead's ability to absorb vibration maintains the correct de gree of flexibility in the entire instal lation. As a matter of interest manv Ia>rge buildings are protected against vibration damage due to rumbling trains and traffic by supporting them on lead-asbestos anti-vibration mats. LI A 2 5 9 4 2 Left. The threaded steei rod is inserted into the hole in the asbe.stos roofing and hooked to the cross beam. Center. The lead seal and tab in place and the entire unit bolted together. Right. After folding the lead tab over the bolt it is hammered down. To minimize corrosion due to gal metal. As the name implies, lead There are many more examples vanic action or adverse atmospheric headed nails are ordinary nails with which illustrate the versatility of conditions, the steei fasteners and soft lead cast around the head. When lead's applicability as a sealing com bolts are frequently lead coated. they are driven home, the soft lead pound. The most common and prob "Top-Side" Fasteners are made from shoulder flattens out permanently, ably one of the earliest uses of lead the following metals: steel, monel, sealing the nail hole against moisture. for this purpose is as a calking mate brass, phosphor bronze, and stainless. The sealing ability and durability rial. Here lead's ability to "give" The Fastener is a typical example of lead also lends itself to the sealing under stress while retaining an effec of an installation which makes use of of caskets where a permanent, tight tive seal has prevented the loss of lead's durability and softness. For seal is imperative. A method of apply millions of gallons of water and < years, lead headed nails have been ing lead in this manner has been in untold thousands of dollars due to used for fastening and, at the same use for many years by the National property damage caused by broken I time, weather-sealing galvanized sheet Casket Company. water mains. Lead Powder For Powder Metallurgy t. EAD powder, one of the newer forms in which this versatile metal is supplied to industry, is finding in Heavy tractor equipped creasingly greater application in the with all-metal "Velveiouct " fust growing powder metallurgical dutches and steering brakes and at right, a variety o' field. Probably the most important "Velvetouch" items in applications today are in the manu facture of leaded-bronze bearings and which lead powder is an important component- bushings, copper-lead bearings, iron- lead bearings, and friction devices. The lead powder used for these purposes is granular in shape and I produced by the atomization process i *> wherein molten lead is forced through ! a small orifice and broken into small particles by a stream of compressed air. inert gas or steam blowing coun ter-current to the molten lead. Avail able particle size ranges from -100 to 350 mesh or in other words, in the case of 350 mesh, small enough to pass through a screen having 350 openings to the linear inch. A mixture of the various sizes is also available. Flake lead powder, which has been --5-- V It LIA25943 o* swim f used commercially for a much longer time than the granular shape, is used primarily as a paint pigment and is produced by ball milling. It is not generally used in powder metallurgy. In the production of bearings and bushings, it is generally agreed that the addition of lead to the metallic constituents of the piece provides ad vantages. such as conformability, imbeadability and anti-frictional prop erties. that add to the efficiency-. and life of the bearing. However, in most instances the mixing and casting of lead with metals having a much higher melting point and lower density is a difficult operation and one that re quires a great amount of care and supervision. For this reason the ad vantages of lead in many instances are more readily realized when pow der metallurgy methods are employed. Many types of copper-base bearings and bushings incorporating lead pow der for the advantages it imparts to the piece are produced in this manner. Some, like the bronzes contain tin and from 4 to 6 per cent lead and others like the straight copper-lead bearings contain up to 45 per cent lead. This last is particularly difficult to cast and by using the powders some of the fundamental obstacles, such as gassing and severe segregation, are detoured. A growing tendency is the use of iron-lead bearings containing up to 10 per cent lead, an alloy that would be Parts made from metal powders. Lett or center are leaded cast iron and right or center, leaded bronze parts. The cap-like centerpiece is a com bination of the two. the cup, leaded cast iron and the dange. leaded bronze. practically impossible by anv other method than powder metallurgy. The addition of lead not only adds to effi ciency of the bearing but also inhibits corrosion of the iron. Lead powder is also an important component in the manufacture ot powdered metal facings for ciutche and brakes, the lead providing amfriction properties as well as conform ability and imbeddabilitv. One com mon mix for facings is, in per cent 73 copper. 14 lead. 7 tin and 6 gra phite. It would be difficult to cas, such an alloy without segregation. These all-metal facings have been used with considerable success or. heavv machinery of all tvpes. such as heavy earthmoving equipment, trac tors and oil field equipment. The' have also been recently introduced into the passenger car and light truck field. Because they are all metal, thev provide longer life and will not dete riorate from exposure to oil or water. Lead powder is also an ideal mate rial for testing dies. Its softness will reflect even minute irregularities in the structure of the die. it has the added advantage of high green strength which permits considerable handling for inspection purposes. Another important use for lead powder is in greases used on open gears and bearings. Federal Housing And Home Finance Agency Exhibits lead Plumbing Shown below is an exhibit of lead plumbing displayed at the 1948 Conference of the American Municipal Association held in Washington, D. C.. December 12-15. 1948. The roughingin was prepared in accordance with the Lnitorm Plumbing Code for Housing, issued by H.H.F.A. --6-- A Portnoi10 of gg^jnericaji r, |;3.a<iniaits j* Cooperstown. New York, Birthplace Of Two American Traditions No. 43 C'JOPERSTOWA. New York, famed for its connection with the great Vinerican novelist. James Fenimore Cooper, has in recent years become doubly important to the American scene by reason of its association with America s national sport, baseball. It is here that many of baseball's im mortals are enshrined for all present and future baseball fans to marvel at and to compare w ith their present-day idols. These two American traditions arc placed in a perfect setting of com fortable stability enhanced by the charm of many old buildings that date designed and built by the founder of back almost to the beginning of the the town, the author's father. William community in 1787. Several of these Cooper, and there is little doubt that beautifully proportioned houses were they were originally painted with pure white lead and oil paint which is still ihe standard paint maintenance mate rial specified for use on many ot them today. Prentice Cottage, built in 1801, another oj ihe Cooperstown landmarks painted with pure white lead and ou paint. The John Worthington house, built in 1802. is one oj ihe earliest examples of the Greek revival in America. Familiarly known as "The White House'' for manv years it is still painted utirn lead paint. t-1 5945 Lead Reducing Bends Ideal For Large Housing Projects ONE of the larger privately fi nanced apartment building pro grams m recent years has been under lay for some time in New York City. L oon completion of this program, there will be available a total of 12.500 multi-story apartment units divided into three projects. The largest of these is Stuvvesant Town with 3.755 units, followed by Peter Cooper \ iilage with 2.495 units and Riverton Apartments with 1.232 units. All are located in the borough of .Manhattan. N. Y., and all are being financed by the Metropolitan Life In surance Co. As can be imagined, the installation of utilities in these projects was a tremendous undertaking. An example of the quantitv of materials that tvas needed in just the plumbing waste and vent systems, was the use of over ing materials ready for installation, 12.500 lead bends and stubs for con completely equipped plumbing shops necting the water closets to the cast- were set up to service each of the proj iron stacks. In projects of this size ects and the lead work was prefabri and height the use of lead connections cated in these shops. Extra-heavy lead between fixtures and rigid piping pro reducing bends with -Ain. inlets and vides the safety factor that prevents 3-in. outlets were used on all but the the destruction of these materials in basement floors; here. 4-in. lead stubs the event of building movement or were used. All upper floor bathrooms settlement. wasted into 3-in. connections to cast To keep a constant flow of plumb iron stacks. To avoid a pocket for substances passing through the lead reducing bends, the reduction in diameter from 4 in. to 3 in. occurs near the outlet end and only on the top and sides, leaving the bottom, when in an in stalled position, perfectly smooth and straight. The plumbing contractor on all three of these projects was the J. L. Murphv Co. of New York Citv. vroy BEQUEST, THE LEAD INDUSTRIES ASSOCIATION WILL BE GLAD TO MAIL '`LEAD" REGULARLY, FREE OF CHARGE. TO THOSE INTERESTED, AND WILL COOTERATE WITHOUT OBLIGATION IN TI1E SOLUTION OF YOCB LEAD PROBLEMS PBINTUJ IN V. 5. A. iY PUBUSHP.15 PRINTINC COMPANY SIW YORK CITY LIA25946