US1686197A - Impervious chemical material and method of its production - Google Patents

Description

patented @ch 2, ll2

stares resale-r WAR/BEN F. BLEEGKER, 01E BDULDER, COLORADO.

'Jl-EPEEVIOUS GEEMICAL MATERIAL AND METHOD ()IFITS BBQDUGTION.

i io Drawing.

' gases and proof against the corrosive action object of the invention,

of acids and other chemicals and which owing to a high degree of tensile strength and elasticity, is particularly adaptedas a substitute for other materials heretofore used for sumlar purposes.

The material is of a composite character and its principal and essential constituent elements are sulfur and a chemically-rcsistant bodyiorming substance, and it is a further to provide in the production of material of a molten mixture of the above stated substances, certain means and treatments which prevent the growth of large sulfur crystals and promote the formation of small crystals desirably to or near the point of being amorphous, and vvhich cause the partic es and molecules of the ingredients to he compacted so as to form a dense and substantially non-porous body devoid of voids gas holes. I

The means above referred to may consist of'a substance which it added to the mixture opposes the formation of large crystals by reaction with the molten sulfur, and the treatn'ients productive of a similar result, may consist in any action which decreases the cooling period of the molten mixture, after it has 7 been termed into the desired shape, to a point of solidification, or in any action prod active 01 an intermolecular movement, and it should he understood that any two or more of the above mentioned exoedients may be combined for co operative action, it sodesired.

Among the substances best adapted to promote the formation of sniallcrystals by reaction with the sulfur, as hereinbefore explained, are those capable of supplying hydrocarbons the required Working temperriod of the molten sulfur nurture and ellect n intermolecular movement in the same,

..t in i pidly coolin by Application filed January 13, 1923. Serial No. 612,514.

artificial means, in agitating or stirri ng the mass to a point of solidification, or'in the proper application of pressure during the cooling period, each action having for its purpose to separately or in conjunction with others, prevent the formation of large sulfur crystals and the occurrence of voids due to gasiiication of the molten sulturyas hereinbe'l'ore explained- An important function of the body giving chemically-resistant substance intermixed with the sulfur, is to give to the material the necessary tensile strength, increase its elastic limits and decrease its co-ellicient of expansion, and among the materials best suited for the purpose may be mentioned artificial graphite, sand, coke and pulverized slate, it being evident that the physical charaeteris-- tics of the material may be varied by the use of different substances of the above type, and

that'their selection is for this reason, governed to a large extent by the particular use or action for which the material or the article produced therefrom is intended and designed.

Inasmuch as artificial graphite is most suitable for the greater number of uses for which the material is intended, the following description Will be limited toits'employment with the understanding that other materials of the above described character may be substituted therefor in the same or ditierent pro--.

portions according to varying requirements and Wrthin the scope oi the present invention.

QillClGD'C method of reducing the solidilieation period of the molten sulfur mixture consists in rapidly cooling a surface With which the fluid mass engages, preferably While the mass is under pressure, which causes the fluid -matter to be compacted and restrained under gradual and progressive solidii'ication.

in the production of pipe linings,the above described action may he obtained by introducing the mixture in a molten condition into a pipe which is heated above the melting tom-- perature and importing to the pipe in a substantially horizontal position, revolving motion about its longitudinal axis which forces the fluid. material to the interior sun face or? the pipe under the influence of corn trifngal force. "While the pipe is thus revolved, its outer surface is cooled by any suit able means such as a continuous application of? cold water or other cooling; fluid, With the till .tlill result that the fluid matter is rapidly solidified progressively from its outer strata which engages with the surface of the pipe, inwardly, while at the same time the inner portion of the liquid mass is continuously fed to the cooling vsurface by the centrifugal pressure.

A microscopic examination of a lining thus produced, reveals a total absence of large crystals and a compact arrangement of molecules without noticeable void-s or crevices. In fact, the crystals are so small as to approach an amorphous condition and the formation is so dense as to be substantially non-porous.

While the above method of forming eonduits and pipe-linings of limited thickness is both practical and effectual, it Will be evi dent that other means may be employed to obtain a similar result and that in the production of machine parts of different character which do not permit of the employment of centrifugal force or of rapid cooling in the aforesaid manner, other methods must be resorted to to obtain the required movement of the molecules in the fluid mixture and oppose the tendency of forming large crystals.

An effectual method of producing the desired result in the production of articles of different forms and proportions consists in subjecting the liquid mass to an agitative or stirring action until it has cooled to a point of solidification. During this action artificial cooling means may be applied to the matrix in which the material is formed, it being understood that in this method as well as in the first described process, rapid cooling of the material from one side to another is highly advantageous. I

Different methods of subjecting the material to pressure while it cools in the required form may be availed of where the employment of centrifugal force is not feasible or practical, and conduits or pipe-linings mayif so desired, be formed by ramming or pressing the fluid matter into a space between the pipe and a therewith concentric core and cooling the exterior surfacethereof as before, or by pouring the molten mixture. into the pipe with a header of sufficient size to forcibly feed the liquid mass to the interior surface of the pipe during the cooling action.

The pressure to which the material is subjected, should always be sufficient to cause the liquid portion of the material to enter into the pores of that which is already partially.solidified by the cooling action upon the surface of the mold and that in the formation of pipe linings and conduits, it is advisable that their thickness should be maintained within certain definite limits on account of the poor conductivity of the sulfur mixture.

In all of the above described actions, the exact nature of the mixture is of secondary consideration provided that it contains an adequate percentage of sulfur, it being evident that the character and proportions of the other ingredients are subject to variation in accordance with different requirements.

It is, however, as stated hereinbefore, Within the scope of the present invention to add to a mixture of sulfur and a finely divided bodygiving substance, other ingredients which aid in adapting it for the purpose of producing an' impervious and chemically-resistant material of the desired degree of density, tensile strength and elasticity, and to form the material from said mixtures by any one or more of the above described actions, and I desire it understood that my invention as herein disclosed, includes the composition of the chemi cally-resistant sulfur mixture as well as the methods of forming it into an impervious material, and that either expedient may be employed separately or in conjunction with the other, as may be desirable to expediently and expeditiously produce a material impervious to liquids and gases, having the desired degree of resistance to the corrosive action of acids and other chemicals.

A hydrocarbonaceous substance such as pitch, if added to the sulfur mixture not only aids in opposing the formation of sulfur crystals, but also prevents the occurrence of voids and the development of cracks by temperature variations, increases the modulus of elasticity and otherwise improves the character of the material and generally enhances its adaptability for the purposes for Which it is intended.

In order to produce the desired chemical combination of the sulfur and the hydrocarbons, the mixture is heated to a point where chemical action takes place, which under ordinary conditions is indicated by frothing and by the evolution of poisonous gases.

The temperature has been found to be above the melting point of sulfur and although at the present time no definite percentage of hydrocarbons can be given, principally owing to the differences in the materials adapted for their provision, it appears that less than thirty per cent of the sulfur content of the mixture produces satisfactory results.

The hydrocarbons by chemically combining with the sulfur, reduce the' size of the sulfur crystals and at the same time permit of admitting to the mixture more hydrocarbons for further chemicalcombination or mere addition, it being understood that aside from the results obtained by chemical re-action, the size of the sulfur crystals will be restricted in inverse ratio to the percentage of hydrocarbons in the mixture.

In reducing the period of solidification of the molten sulfur mixture by rapid artificial cooling, a ratio may be maintained between the temperature of the cooling medium, the time of applicat ion and the percentage of hydrocarbonsin the mixtlu'e, it being apparent that owing to their similar functions in the production of the material, the factors should be proportioned so as to co-operate without waste of time, labor or material, toward the production of a material of the required character.

lVhile in the foregoing description, hydrocarbons have been mentioned as best adapted to produce the desired action upon the sulfur, it should be remembered that as mentioned hereinbefore, other materials having similar functions, may be employed within the spirit of my invention.

What I claim and desire to secure by Letters Patent is:

1. An impervious chemically-resistant material having in intermixture with artificial graphite, sulfur and solid hydrocarbons'chemically combined.

2. An impervious chemically-resistant material consisting of artificial graphite intermixed with a chemical combination of sulfur and a hydrocarbon having a high melting point.

3. An impervious chemically-resistant material consisting of artificial graphite intermixed with a chemical combination of sulfur I and pitch.

In testimony whereof'I haveaflixed my signature.- v

WARREN F. BLEEOKER.