Читать книгу The Art of Lead Burning - C. H. Fay - Страница 4
ОглавлениеCHAPTER I.
INTRODUCTION.
In compiling a treatise on the subject of lead burning too much stress cannot be laid upon the fact that the greatest care must be taken to observe the smallest details and to follow carefully every suggestion in regard to safety. I am aware of the responsibility resting upon me in placing this article into hundreds of hands, comparatively ignorant of the danger involved in handling so much hydrogen, without thoroughly instructing them in detail as to its use. I may be excused, therefore, if, for that reason, some of the explanations are so simple as to seem ridiculous; but my aim is to present to the trade a treatise that can be relied upon to be free from theory that has not been thoroughly tried and tested, so that the beginner can be sure that, if he follows directions as printed, nothing but satisfaction to him can result.
Study the Chapter on Hydrogen Gas.
I cannot too strongly recommend that the beginner study the chapter on hydrogen gas until the main points are memorized and clearly understood. The experiments should be performed and the result carefully noted for future reference before attempting to use the generator. It is time well spent to master the technical parts thoroughly before attempting the mechanical part. Then when a man takes up the mechanical he will do so with an intelligent understanding of what he is doing, and any little trouble which may then arise can be quickly overcome.
Another thing to be observed is to avoid nervousness. A nervous person cannot do this work with any degree of satisfaction, as it requires a cool head and a steady hand and a vast amount of patience to burn the upright and inverted seams.
Lead Burning Explained.
Lead burning is the process of fusing two pieces of lead together without the use of solder. The process consists in melting the edges together, a drop at a time, and when done with hydrogen gas and the blow pipe is called the “autogenous process.” Lead can be fused with gasoline or illuminating gas by the use of the compound blow pipe; but, as ordinary gases give an oxidizing flame and require a flux, it is not considered a practical method.
Fig. 1.—Lead Burning Apparatus.
Lead is used extensively in lining tanks made to contain pickle dips, hot cyanide solution, storage batteries, acid tanks for manufacturing jewelry and water closet tanks, as water in many cases contains large quantities of lime and other deposits which rapidly destroy the solder used on copper linings. Tanks used for the above purposes must be lined with lead and the seams burned, as acids attack the tin in solders and destroy them. The demand for the work is rapidly increasing where it is introduced. I have demonstrated to many manufacturers that this is the cheapest method known, as it gives a permanent solution of the problem how to keep a chemical tank tight.
Method of Making Lead Lined Tanks.
The most common method resorted to in many large factories is to make the tanks out of very heavy cypress lumber, free from any knots or blemishes. The joints are carefully dovetailed and fitted together, and long bolts are used to draw the joints and keep them from leaking. Usually it takes from three to four days to complete one small tank, only to have it leak in a few months; whereas the same tank can be built in a few hours of any cheap lumber, and then, when it is lined with lead of a proper thickness and the seams burned it will usually last for an indefinite period, thereby saving floors and, many times, costly plating solutions.
The most common argument put forth by manufacturers is that the bottoms of lead lined tanks are soon cut out, owing to dropping sharp pieces of metal into them. This difficulty can be best overcome by placing a slatted bottom of wood in the tank, holding the same in place with strips of sheet lead, one end of which has been previously burned to the bottom of the tank. These strips are to be brought up through the slats and then bent over the top of them. This will keep the wood from floating, and is the only practical way to do it, as the false bottoms soon decay, and can be easily removed and replaced by simply bending back the strips of lead.
General Remarks.
Soft solder, as referred to here, means solder that melts at a temperature of 300 degrees or less, and is so called because of the low heat required to fuse the solder. It is used almost exclusively on the quick melting metals and compositions, such as block tin pipes and Britannia metal. It is also used by pattern makers in soldering white metal, as it requires but very little heat to sweat it through heavy articles. It should not be used to join any pipes which convey hot water or other hot liquids, as it is readily acted upon and destroyed. (The composition of these solders is explained in a special chapter.)
The chapters on blow pipe work, also on bar work, will alone turn many dollars into the pockets of the plumbers who have courage and ambition to acquire this line of work. Many times small leaks occur in difficult places that can be readily repaired by the use of the blow pipe and a common candle.
The lining of bars with Britannia metal is coming more and more into general practice, and it usually requires a specialist in this line to do the work. The soldering of this metal with a blow pipe and an alcohol torch is an easy matter, and is described in a special chapter.
There is no reason why this work should not be done by a plumber, particularly in small cities and towns, and to aid such as have not had the opportunity to familiarize themselves with such work I append such diagrams as may seem useful and necessary.
