Document oR9w29Nzg0Kj5zXQwEGaOnQE

PLAINTIFFS EXHIBIT JM 1071 Industry Shows Remarkable Gr Tq IMPROVE ROCK WOOL MANUFACTURE By BROR NORDBERG robably, the most rapidly growing perimentation by manufacturers and Prock products industry during the others interested has resulted in a finer past few years, and particularly in 1937,product. has been the manufacture of mineral wool--from the standpoint of increase in the number of plants, the tonnage produced, and the development of oper ating technique. Surveys of the industry, however, re veal a marked lack of standardization. Certainly a great many varieties and qualities of rock wool are now on the market. The cupola is the standard method of manufacture, but it is doubt ful if any two companies are consistent in their regulation of the wool making Production Statistics Encouraging Production of mineral wool in 1928 for the United States was 50.000 tons. In 1937, the estimated capacity was 500.000 tons. The number of plants has increased from eight in 1929 to 60 in 1937; truly a remarkable growth. A number of established stone producers are manufacturing rock wool as a by product. federal flock Wool process. Differences in the types of raw Plant ol Kansas City materials, their chemical composition Typical practices can best be treated and melting points; proportion of the by discussing operating methods of a batch; the quality and purity of fuels; new modem plant. The plant which we the melting temperatures; temperatures have chosen is that operated by the of the molten mass when "blown"; air Federal Rock Wool Co., Kansas City. Mo. and steam pressures; and structural de This plant is owned by a producer of sign of the cupola, all have their influ commercial crushed stone and its origi ence on the quality of the Anal product. nal design incorporates several interest In spite of this lack of standardiza ing features. tion, builders have created a demand for Materials from which mineral wool is an efficient insulating material, and ex made are very numerous and include calcareous shales, metallurgical slags, sand, soda ash and limestone and waste glass, combination of dolomites and limestone with shale or clay, old china or crockery, firebrick and sometimes top soil. At the plant under consideration, vari ous rocks are blended and melted to make a lightweight, white wool of low thermal conductivity, and the process has been largely developed by the "trial and error" method. The plant is within a short hauling distance from the commercial stone mines. Stone from these mines, with a calcium carbonate content of about 90 percent, makes up about 50 percent of the materials charged into the cupola. Louis Marino, president of the com pany, developed the process and de signed the plant. Several of the original features of the plant are unprotected by patents and the methods by which the process was developed were not the out come of chemical analyses but by ex perimentation. It is therefore inadvis able and Impractical to go into all de tails of the manufacture of wool at this plant. Blowiaq th* mohta reck by steam lolo the collecting chamber at the new plant of Federal Bock Wool Co. The cupola le water-lacketed to It* loll height and iteam ie generated to pressures exceeding 100 pjJ within the water lackef. When the lire is started in the cupola. throe hours are needed to reach the desired pressures. Steam is blown through a single stream of molten rock in front of the chamber opening Blend 23 Varieties ol Stone lor Feed Mr. Marino, the president of the Fed eral Rock Wool Co., has been interested in the production of stone in Jackson county for over 20 years, and has uti lized his knowledge of rocks in the sur rounding country to advantage in for mulating a proper blend for rock wool. According to Mr. Marino, some 500 dif ferent rocks, including limestone, flints and others of igneous origin, are avail able in Jackson county and his selection for the feed into the cupola has been determined by actual experimentation and without knowledge as to which are basic and which are acidic. The most successful batch of raw materials consists of 23 varieties of rock, including the Bethany stone, all of which are trucked to the plant from within a radius of 25 miles. The hair trigger control used in blending various stones has proven to be of the utmost importance. This close control results in the production of a wide variety of rock wools with considerable differences in physical properties, just by slight changes in the constituents. While about 50 percent of the feed comes from the commercial stone mines, on the other 94 ROCK PRODUCTS MTC 017199 Jflrv. /<? Z? hand, as little as six tons of another variety is used in three weeks of opera tion, to make the best wool for domestic use. All stone is trucked to the plant bins. Truckers are hired by Mr. Marino to "pick up" the different rocks from charted locations. Stone feed is propor tioned according to exact weights. The plant itself is a new 42- x 115-ft. stone veneer building, designed for installa tion of a second cupola at a future date. Although the manufacturing process, the method of collecting the wool and its handling, in the main, are similar to those used in other plants firing cupolas, the equipment has structural features that are somewhat different. The cupola is essentially an old steam boiler, without the flues, with a 6-ft. outside diameter, and is 14 ft. in height. It Is water-jacketed to its full height with a 3- to 6-in. space between the outer wall and the jacket shell. General* Steam in Wafer Jacket Steam for blowing the molten rock into the collecting chamber is generated within the water Jacket, simultaneously with the melting of the rock and not from an outside source. When the Are is started in the cupola and coke is added, about three hours is required to develop the desired steam pressures to "blow" the wool. Steam pressures are varied between 100 and 125 p.s.i. Two reserve steam pressure tanks of 1200 Battle arrangement is tbo collecting cbambor. which successfully rtcorert macb of tbo fine product tbat would olbsrwiso pass out tbo ttack witb tbe exhaust steam Bait et rock wool an mtarurod by marking knirtt and cat to sin as (he wool It carried oror tbo coaroyor from tbo collocttno ehambor. toon wool ncorcnd In auxiliary chambort ft collected and removed by merino lb* cbambers tbroaob tbs doorways sssn on tbs right. Tbs man In tbs torsoround an boxino tbs wool product, fo tbs Istf of tbs conrsyor an /. C. Hoorsr. vice-president. Louis Marino, prssidsnf. and . /. Flinn. sscrslary-tnasurer ot Federal Rock Wool Co.. Iron left to right gal. and 400 gal. capacities are provided. Alternate beds of coke and stone are fed into the cupola in the conventional manner and the molten rock flows into the path of the steam jet from a single opening. The quality of the finished product is influenced, and its physical characteristics varied, by changes in the coke-stone ratio. Rock wool is blown into a collecting chamber 48 ft. in length, 12 ft. high and 6 ft. wide. The illustration shows the rolls which are not anchored to a fixed position, but are allowed to slide up and down through a 12-in. channel bar. The bats are cut by hand into 15- x 23-in. sizes to the desired wall thicknesses, and boxed in cardboard boxes direct from the cutting table. The conventional box contains 24-sq. ft. of rock wool in bats. Battle Arrangement To Recover Fine Wool In the accompanying sketch is shown how approximately a ton per day of fine wool, which ordinarily would be carried away with the exhaust steam out through the stack, is recovered. The mixture of steam, or air. and wool must pass through a circuitous route on its way to the stack, and the "baffle" arrange ment arrests the speed of fine particles to the point where practically all the wool in suspension is dropped into two chambers and recovered. At the point where the air exhausts to the outside. the chimney has a horizontal baffle to force much of the very fine material not already settled out in the first two chambers to fall into the third chamber. Thus far, the only test made on the insulating qualities of the rock wool was made before it was perfected to the present degree. This test, made by the Kansas City Testing Laboratory, gave a thermal conductivity of 0.26 B.t.u. per hour per sq. ft. and with a temperature gradient of 1 deg. F., per inch of thick ness. A 35a-x 15-x 23-in. bat picked at random from the commercial wool stored in cardboard containers weighed 314 lb. or 4.48 lb. per cu. ft. The methods of operation may, of course, be changed to give a wool varying widely in quality and weight. In addition to bats, loose wool and granulated wool are produced. Trim scraps are thrown into a home-made shredder and the shredded wool is car ried over a bucket elevator, 37-ft. cen ters. and chuted through a 25-ft. cir cular screen to a 6-ton bin. Shot is removed through the 14-in. screen open ings. The shredded product is packed directly out of the bin chutes into 35-lb. paper bags. Plant capacity per 24 hr. is 300 boxes or 7200 sq. ft. of bats. 3%-in. thick, a ton of granulated wool, and a ton of loose wool. Officers of the com pany, besides Mr. Marino, are J. O. Hoover, vice-president and E. J. Flinn. secretary-treasurer. JANUARY, 1938 MTC 017200 95