Fig. 70.--"Banjo."Fig. 70.—"Banjo."
Fig. 70.--"Banjo."Fig. 70.—"Banjo."
Piping.—From the service pipe on which there has been placed a shut-off, a line of piping, full size, is run through the basement, overhead to a convenient place, perhaps to a partition in the center of the cellar. The pipe is brought down and connected into the end of a header. This header or banjo is made of Ts placed 4 inches center to center. From each T a line of pipe is run to each isolated fixture or set of fixtures (seeFig. 70). A stop and waste cock is placed on each line at such a point that all stop cocks will come in a row near the header. A small pipe is run from the waste of each stop and discharged into a larger pipe which connects with a sink. This way of running pipes while it is expensive makes a very neat and good job. Each stop cock has a tag on it stating explicitly what it controls. If the building is a large one a number of these panelled headers are used. A less expensive way to run this pipe is to branch off from the main at points where the branch pipe will be as short as possible and use as few fittings as possible. Stop and waste cocks are then placed on eachbranch near the main.
All pipe must follow the direct line of fitting with which it is connected. The line of pipe should be perfectly straight. If it seems necessary to bend the pipe to get around an obstacle, then good judgment has not been used in placing the fitting into which the pipe is screwed. The fitting should be re-located so that the pipe can be run without bending. To have true alignment of pipes the whole job or section of the job must be drawn out on paper first and any obstacles noted and avoided before the piping is cut. This not only saves time but it is also the forerunner of a good job. When getting measurements for piping the same rule or tape should be used to get out the pipe as was used to get the measurements.
The water main and branches that run through the basement of a building are generally hung on the ceiling. Rough hangers of wood, rope, or wire are usually used to hold the pipe in place at first, then neat and strong adjustable hangers are placed every 8 feet apart. There are in use too many kinds of hangers to explain or describe them here. The essential point of all good hangers is to have them strong, neat, and so made that perfect alignment of the pipe can be had. The hangers should be so placed that no strain will come on the fitting or the valves. A hanger should be placed near each side of unions so that when the union is taken apart neither side of the pipe will drop and bend. Hooks and straps should be used to hold vertical pipes rigid and in position. A vertical pipe should be so held in place that its weight will come on the hooks and straps that hold it rather than on the horizontal pipe into which it connects. Where there are six or eight horizontal lines of pipes close together, a separate hanger for each pipe makes a rather cumbersome job and it consumes considerable time to install them properly. A hanger having one support run under all the pipes will allow space forproper alignment and adjustment for drainage. Allowance must be made on all lines of pipe for drainage. When a building is vacant during cold weather, the water is drawn off; therefore, the pipes should have a pitch to certain points where the pipes can be opened and the entire system drained of water.
Kinds of Pipe.—The kind of pipe that is used for cold-water supply depends on and varies according to the kind of water, the kind of earth through which it runs, and the construction of the building. Wrought iron, steel, lead, brass, tin-lined brass, are in use.
The supply pipe to every fixture should have a stop on it directly under the fixture. This will allow the water to be shut off for repairs to the faucet without stopping the supply of other fixtures.
The making of perfect threads on pipe is an important matter, especially on water pipes. If the pipe and the dies were perfect, and the mechanic used sufficient oil in cutting, and the fittings were perfectly tapped to correspond to the dies used on the pipe, of course a perfect union between pipe and fitting would result and the joint would be found to be perfect on screwing the pipe home. As all the above conditions are not found on the job, threads are made tight by the use of red or white lead and oil. The lead is put on the thread and when the thread is made up the lead will have been forced into any imperfection that may be in the threads and the joint will then be water-tight. White lead and oil should be used on nickel-plated pipe as other pipe compounds are too conspicuous and look badly. A pipe compound should be used with discretion, for if too much is put on a burr of it will collect in the bore of the pipe and reduce it considerably. This is not tolerated, so only a small amount is used. Water pipes should be run in accessible places, making it possible to get at them in case of trouble. In climates that have freezing weather water pipes should notbe run in outside partitions. If it is found absolutely necessary to do so, as in the case of buildings which have no inside partitions on the first floor, the pipe should be properly covered and protected. The different methods of covering pipes are described inChapter XV.
The problem of supplying hot water to plumbing fixtures is one that has required years of study. Each job today demands considerable thought to make it a perfect and satisfactory hot-water system. We will find installations today where the water is red from rust, where there is water pounding and cracking. There are also jobs where the fixtures get practically no hot water. As each job or individual building has its own peculiar conditions, they must be solved by the designer or the mechanic, using the fundamental principles of hot-water circulation. We must first know how much hot water is to be used, also the location of the outlets and the construction of the building; then the size of the pipes and the size of the tanks and their locations can be settled. If the job is a large one, a pump may be employed to insure the proper circulation. After this the pipe sizes and connections can be worked out. The one great enemy of hot-water circulation is air. Therefore, no traps or air pockets should ever appear in the piping system. The boiler, as it is often referred to, is the hot-water storage tank. A copper or iron tank holding sufficient water to supply all fixtures, even when every fixture demands a supply at the same time, is installed in a convenient place and the heating arrangement connected with it. A thermostat can be placed on the system and the temperature of the water controlled. According to the size of the building the problem of furnishing the plumbingfixtures with hot water increases.
Methods of Heating Hot Water.—There are a number of ways of furnishing hot water. Some of the installations are listed below.
A cast-iron or brass water back is placed on the fire pot of a stove or furnace. A separate stove with the fire pot and water jacket is used. A coil of steam pipe is placed inside a hot-water boiler or tank. Gas coil heaters are connected with hot water storage tank, also gas coil instantaneous heaters are connected with the piping direct.
Combinations of the above systems are in use and serve the purpose for which they are intended. For instance, the tank can be connected with a coal range and a gas coil heater, heat being furnished by the range alone or the coil heater alone, or both can be used at the same time. This combination can be connected with the furnace in the cellar, and during the winter months, when the furnace is in use, the water can be heated by the furnace coil. In warm weather, when the furnace is out, the range can supply the necessary heat. In hot weather the coil gas heater can supply the heat.
Connections of Tank and Heating Apparatus.—The ordinary house boiler or hot-water storage tank has four connections, two on top, one on the side, and one on the bottom. The top connections are used for the entrance of cold water into the tank and for the supply of hot water to the fixtures (seeFig. 71). The cold-water inlet has a tube extending into the tank below the side connection. This tube has a small hole filed in it about 6 inches from the top. This hole is to break any syphonic action that may occur at any time. The side connection is for the connection of the pipe coming from the top of the water back. The bottom opening in the tank is for the connection of the pipe coming from the lower water back connection, also for draining the boiler. The circulation of the water can be followed thus:cold water enters the boiler in the tube and discharges into the boiler below the side connection. From here it flows out of the bottom connection into the water back, through the upper connection into the boiler, through the side opening, then to the top of the boiler and out to the fixtures through the fixture supply opening.
Fig. 71.--Storage tank, and coil heater with thermostatic control valve.Fig. 71.—Storage tank, and coil heater with thermostatic control valve.
Fig. 71.--Storage tank, and coil heater with thermostatic control valve.Fig. 71.—Storage tank, and coil heater with thermostatic control valve.
Fig. 69shows a thermostatic control valve attached to the bottom of a heater coil, and at the side of storage tank. The best arrangement is at the bottom, for it does not shut off the gas supply until the boiler is full of hot water.
Connecting Tank and Coil Gas Heater.—The boiler and the coil gas heater have a different connection. The bottom of the tank and the bottom of the heater are connected. The top of the heater and the top of the boiler are connected. The accompanying sketch shows how thisconnection is made. If the tee on the top of the boiler into which the gas-heater connection is made is not the first fitting and placed as close to the outlet as possible, the water will not circulate freely into the boiler. This connection according to the drawing should be studied and memorized.
Fig. 72.--Instantaneous gas heater. Showing circulation heater or booster.Fig. 72.—Instantaneous gas heater. Showing circulation heater or booster.
Fig. 72.--Instantaneous gas heater. Showing circulation heater or booster.Fig. 72.—Instantaneous gas heater. Showing circulation heater or booster.
Instantaneous Gas-heater Connections.—An instantaneous gas heater is placed in the basement. The copper coil in it is connected at the bottom with the cold-water supply and the top outlet of the coil is connected with the hot-water system of piping. There is no need of a storage tank with this heater. When a faucet is opened in any part of the hot-water piping system, the water passing through the water valve at the heater causes the gas valve to open so that the whole set of burners in the heater is supplied with gas, and the burners are lighted from a pilot light. When the faucet is closed, the gas supply is shut off and the burners are put out. The pilot is lighted all the time. Space will not permit going over these connections in detail.It is a large field and requires considerable thought.
Safety and Check Valves.—When a meter is used on a water system, the water company demands that a check valve be placed on the hot-water system to prevent the hot water from being forced back into the meter in case the pressure got strong enough in the boiler. If a check valve is used for this purpose, or for any other purpose, a safety valve must be placed on the boiler piping system to relieve any excessive pressure that may be caused by having the check valve in use. There is today, with meters of modern type, no reason to use a check valve or a safety valve. If an excessive pressure is obtained in the boiler, it is relieved in the water main.
When water is heated, it expands. If the heat becomes more intense and steam is formed, the expansion is much greater, and some means must be provided to allow for it. This expansion can be allowed to relieve itself in the water main as explained above. When a check valve is placed on the piping, this means of escape is shut off and a safety valve must be employed. Without these reliefs, the pressure would be so great that an explosion would result. When steel pipe and steel boilers are used for storage tanks and connections, the pipe and tank will shortly start to rust and parts of the piping are stopped up with rust scales. The water also becomes red with rust when the water becomes hot enough to circulate. When the pipes are stopped up, steam is formed and a snapping and cracking sound is heard. To avoid these conditions, the piping should be of brass or lead and the storage tank should be of copper. The installation cost of brass and copper is greater than steel, but they will not have to be replaced in two or three years, as is the case with other material. A valve should be placed on the cold-water supply to control the entire hot-water piping system. A pipe with a stop cock should be placed underneath the boiler and should extendinto a sink in the basement so that the boiler can be drained at any time for cleaning or repairs.
Connecting with Fixtures.—To have all fixtures properly supplied with hot water it is necessary to run what is termed a circulating pipe. This circulating pipe is a circuit of pipe extending from the top of the boiler to the vicinity of the fixtures and then returning to the boiler and connecting into the pipe leading out of the bottom of the boiler. From this circuit all branches are taken to supply all fixtures requiring hot water. This circulating pipe has hot water circulating through it all the time. Therefore the fixtures are supplied with hot water very quickly. The circulating pipe and its branches are run without any traps or air pockets.
Fig. 73.--Expansion loop. Four 90° ells.Fig. 73.—Expansion loop. Four 90° ells.Fig. 74.--Expansion loop. Five 90° ells.Fig. 74.—Expansion loop. Five 90° ells.Fig. 75.--Expansion loop. Six 90° ells.Fig. 75.—Expansion loop. Six 90° ells.
Fig. 73.--Expansion loop. Four 90° ells.Fig. 73.—Expansion loop. Four 90° ells.
Fig. 74.--Expansion loop. Five 90° ells.Fig. 74.—Expansion loop. Five 90° ells.
Fig. 75.--Expansion loop. Six 90° ells.Fig. 75.—Expansion loop. Six 90° ells.
When running the piping, it should be borne in mind that not only does the water expand when heated, but the pipe expands also. Therefore due allowance must be made for this expansion. The long risers should have an expansionloop as shown in Figs.73,74and75. There are installed on some jobs what is known as an expansion joint. This will allow for the expansion and contraction of the pipe. The writer's experience with these joints has not been very satisfactory. After a while these joints begin to leak and they must have attention which in some cases is rather expensive. An expansion loop as shown in the sketch, made with elbows, will prove satisfactory. If the threads on the fittings and pipe are good, no leak will appear on this joint.
All gas heaters must be connected with a flue to carry off the products of combustion.
Pipe Covering.—Pipe covering is another important branch of plumbing. A few years ago heating pipes were the only pipes that it was thought necessary to cover. The ever-increasing demands made by the public keep the wideawake plumber continually solving problems. The water running down a waste pipe, for instance, will annoy some people, and provision must be made to avoid this noise or to silence it. This is one of the many problems that the plumber must solve by the use of pipe covering.
Pipes that Need Covering.—First of all, the covering must be put on properly to be of high service.Hot-water circulating pipesneed covering to reduce the amount of heat loss. If the pipes and the tank are not covered, considerable more fuel will be needed to supply the necessary amount of hot water than if the pipes and tank were covered with a good covering.Cold-water pipesneed covering in places to keep them from freezing. They also need covering under some conditions to keep them from sweating. They are covered also to prevent the material which surrounds them from coming into direct contact with the pipe.Waste pipesneed covering to prevent them from freezing and to silence the noise caused by the rush of water through them.Ice-water pipesare covered to prevent the water from rising in temperature and to prevent any condensation forming on the pipe. There is need for such a variety of covering that I have listed below some of them and themethods employed for putting them on the pipe.
Magnesia, asbestos air cell, molded asbestos, wool felt, waterproof paper and wool felt, cork, hair felt. These coverings come in the form of pipe covering with a cloth jacket. They also come in the shape of fittings as well as in blocks and rolls of paper, and in powdered form. Any thickness that is desired may be had. The pipe covering is readily put on the pipe. The cloth jacket is pulled back a short distance and the covering will open like a book. It can then be clamped on the pipe and the jacket pulled back and pasted into place. Brass bands, 1 inch wide, come with the pipe covering. These are put on and the pipe covering is then held securely in place. Practically all the coverings are applied in this manner and are made up in 3-foot lengths to fit any size pipe. To cover the fittings and valves, the same kind of sectional covering can be obtained and applied in the same manner as the pipe covering. Plastic covering is often applied to the fittings and molded into the shape of the fitting. The plastic covering comes in bags and is dry. It is mixed with warm water to the consistency of thick cement and applied with a trowel. When the covering is put on the pipes and fittings, it should be done thoroughly to get satisfactory results. Each section of the covering has on one end an extra length of the jacket. This is to allow a lap over on the next section to make a tight joint. If the sections need fitting, a saw can be used and the covering cut to any desired length.
Magnesiacovering is employed mostly on steam pipes, especially high-pressure. This material can be had in the shape of pipe covering, in blocks, or cement.Asbestos air cellcovering is employed to cover hot-water circulating pipes. It is constructed of corrugated asbestos paper. This material is manufactured in the sectional pipe covering or in corrugated paper form.Molded asbestoscovering is also used on hot-water pipes,and is manufactured in pipe covering or in blocks.Wool feltcovering is used mostly on hot-water pipes and makes one of the best coverings. It is lined with asbestos paper and covered with a cloth jacket.Waterproof paper and wool feltis used on cold-water pipes and is made in 3-foot lengths. The covering is lined with waterproof paper and covered with a cloth jacket.Cork.—A heavy cork covering is one of the best coverings for ice-water pipes, and a light cork covering is used for cold-water pipes. This covering comes in sections as other coverings, also in blocks and sheets.Hair feltis used to prevent pipes from freezing. It comes in bales containing 150 to 300 square feet of various thicknesses.
Magnesiacovering is employed mostly on steam pipes, especially high-pressure. This material can be had in the shape of pipe covering, in blocks, or cement.
Asbestos air cellcovering is employed to cover hot-water circulating pipes. It is constructed of corrugated asbestos paper. This material is manufactured in the sectional pipe covering or in corrugated paper form.
Molded asbestoscovering is also used on hot-water pipes,and is manufactured in pipe covering or in blocks.
Wool feltcovering is used mostly on hot-water pipes and makes one of the best coverings. It is lined with asbestos paper and covered with a cloth jacket.
Waterproof paper and wool feltis used on cold-water pipes and is made in 3-foot lengths. The covering is lined with waterproof paper and covered with a cloth jacket.
Cork.—A heavy cork covering is one of the best coverings for ice-water pipes, and a light cork covering is used for cold-water pipes. This covering comes in sections as other coverings, also in blocks and sheets.
Hair feltis used to prevent pipes from freezing. It comes in bales containing 150 to 300 square feet of various thicknesses.
"Durham" or "screw pipe" work is the name used to denote that the job is installed by the use of wrought-iron or steel screw pipe. We speak of a "cast-iron job" meaning that cast-iron pipe was used for the piping. A completely different method of work is used when screw pipe is employed for the wastes and vents. When screw pipe is to be used or considered for use, it is well to know something concerning the various makes of screw pipe. Nothing but galvanized pipe is ever used. The value of steel screw pipe and wrought-iron screw pipe should be studied, and every person interested should, if possible, understand how these different pipes are made and how the material of which they are composed is made. In some places one pipe is better than another and a study of their make-up would enlighten the user and allow him to use the best for his peculiar conditions. The maker's name should always be on the pipe. The following table shows the sizes, weights, and thicknesses of screw pipe:
SizeThicknessNo. threadsper inch11⁄40.140111⁄211⁄20.145111⁄220.154111⁄221⁄20.204830.217831⁄20.226840.237850.259860.2808
Screw pipe work came into common use with the advanceof modern steel structures. Some difficulty had been experienced in getting the cast-iron pipe joints tight and to keep the pipe so anchored that it would not crack. The screw pipe was found to answer all of the requirements of modern structures and therefore has been used extensively. The life of screw pipe is not as long as extra heavy cast-iron pipe. This is the only serious objection to screw pipe, which must be renewed after a term of years, while extra heavy cast iron lasts indefinitely. Screw pipe is never used underground. When piping is required underground, extra heavy cast-iron pipe is used.
The pipe used in Durham work is galvanized extra heavy, or standard wrought-iron, or steel pipe. It is almost impossible to recognize wrought-iron from steel pipe without the aid of a chemical or a magnifying glass. To test the pipe to distinguish its base, take a sharp file and file through the surface of the pipe that is to be tested. If the pipe is steel, under a magnifying glass the texture of the filed surface will appear to be smooth and have small irregular-shaped grains, and there will also be an appearance of compactness. If the pipe is iron, the texture will have the appearance of being ragged and will show streaks of slag or black. When screw pipe is cut there is always left a large burr on the inside of the pipe. This burr greatly reduces the bore of the pipe and is a source of stoppage in waste pipes. After the pipe is cut this burr should be reamed out thoroughly. One of the strong points of screw pipe is the strength of each joint. Care should therefore be taken to see that perfect threads are cut on the pipe and that the threads of the fittings are perfect. The dies should be set right and not varied on each joint. There should be plenty of oil used when threads are cut so that the threadwill be clean and sharp. The follower or guide on stocks should be the same size as the pipe that is being threaded, otherwise a crooked thread will result. If a pipe-threading machine is used, the pipe is set squarely between the jaws of the vise that holds the pipe in place. When cutting a thread on a long length of pipe, the end sticking out from the machine must be supported firmly so that no strain will come on the machine as the pipe turns. It is necessary to cut crooked threads sometimes on the pipe to allow the pipe pitch for drainage or to bring the pipe into alignment where fitting would take up too much room. To cut a crooked thread on a piece of pipe, simply leave the follower out of the stock or put in the size larger. The dies not having a guide will cut a crooked thread. Piping should be run with as few threads as possible. With a thorough knowledge of and the intelligent use of fittings, a minimum number of threads will result.
The pipes in a building are run in compact parallel lines in chases designed especially for them. The tendency is to confine the pipes to certain localities as much as possible. This makes a very neat job and in case repairs are needed, the work and trouble incurred will be confined to one section.
The fittings used in screw pipe work are cast-iron recess type (seeFig. 54). The fittings are so made that the inside bores of the pipe and the fittings come in direct line with each other, thus making a smooth inside surface at all bends. The fittings are all heavily galvanized. All fittings should be examined on the inside for any lumps of metal of sufficient size to catch solid waste matter, and these must be removed or the fitting discarded. All 90° bends, whether Ts or elbows, are tapped to give the pipe that connects with them a pitch of at least1⁄4inch to the foot. Except whereobligatory, 90° fittings should not be used. To make a bend of 90° a Y-branch, a nipple and a 45° bend should be used, or two 45° bends will make a long easy sweep of the drainage pipes and reduce the possibility of stoppage.
Y-branches are inserted every 30 feet at least to allow for a clean-out which can be placed in the branch of the fitting. When a clean-out is placed an iron plug should not be used. These plugs are not removed very often and an iron plug will rust in and be almost impossible to get out. Brass clean-out plugs are used and are easily taken out.
At times it is necessary to connect cast iron and wrought iron, or in a line where a union could be used if the pipe were not a waste pipe, a tucker fitting is used. This fitting is threaded on one end and has a socket on the other to allow for caulking. To get a good idea of all the fittings in general use, the reader should get a catalogue from one of the fitting manufacturers and a survey of it will give the names and sizes of the fittings. However, I show a few common ones. In the writer's opinion, the studying of the catalogue would be of more benefit than a description of fittings at this point. The sizes used and the methods employed to vent the waste-pipe systems are the same as in cast-iron work.
The hanging of screw pipe is a very essential point. The taking of the strain off from a fitting or line of pipe by the use of a hanger is the means of avoiding serious trouble after a job is completed. On horizontal runs hangers are placed not more than 8 feet apart. In a building constructed of wood, the hangers are secured to the joists. In a building constructed of steel beams and concrete the hangers are secured to the steel beams by means of I-beam hangers that clamp on the beams; also in the case of concrete the hangers are extended through the floor and a Tis put on the hanger on top of the cement floor; an iron bar or a short piece of smaller pipe run through the T holds the hanger in place and secures it rigidly. The finished floor is laid over the hanger so that it does not show from the top. Hangers on the vertical lines should be placed at every joint and under each fitting. To have the pipe in true alignment, the hangers must be hung and placed in line. Every riser line must have an extra support at the base to avoid any settling of the stack which will crack the fittings and break fixture connections.
The proper installation of screw pipe work requires getting correct and accurate measurements. Every plumber is or should be able to get correct center to center, center to end, end to end, center to back, and end to back measurements. In Durham work 45° angles are continually occurring. To get these measurements correctly, the following table has been compiled as used by the author and found to be correct. The reader should memorize it so that it may be used without referring to the book.
Soil pipeScrew pipeMultiplier1⁄6bend601.151⁄8"451.411⁄12"302.001⁄16"221⁄22.611⁄32"111⁄45.121⁄64"55⁄810.22
Before any measurements are taken, the lines of pipe are laid out and the position of each fitting known. As I have stated before, the plumber must look ahead with hiswork. He must have the ability of practically seeing the pipe in place before the work is started. This requires experience and judgment. Before the measurements are taken and the pipe cut consideration must be given to the fact that the fittings and pipes must be screwed into position. Therefore, "can the fitting on the pipe be placed where it is laid out when this is considered?" must be one of the many questions a plumber should ask himself. Allowance must be made for the chain tongs to swing. Whenever possible, a fitting is made up on the pipe while the pipe is in the vise.
Fig. 76.--The offset is B or 12 inches center to center. The offset is made using 45 degree fittings. Therefore the length of A from the center of one fitting to the center of the other is B × 1.41 = 12 × 1.41 = 16.92 inches.Fig. 76.—The offset is B or 12 inches center to center. The offset is made using 45 degree fittings. Therefore the length of A from the center of one fitting to the center of the other is B × 1.41 = 12 × 1.41 = 16.92 inches.
Fig. 76.--The offset is B or 12 inches center to center. The offset is made using 45 degree fittings. Therefore the length of A from the center of one fitting to the center of the other is B × 1.41 = 12 × 1.41 = 16.92 inches.Fig. 76.—The offset is B or 12 inches center to center. The offset is made using 45 degree fittings. Therefore the length of A from the center of one fitting to the center of the other is B × 1.41 = 12 × 1.41 = 16.92 inches.
The fixture connections when screw pipe is used are necessarily different than when cast-iron pipe is used. A brass nipple is wiped on a piece of lead pipe and then screwed into the fitting left for the closet connection. The lead is flanged over above the floor and the closet set on it. The lead is soldered to a brass flange. The brass flange is secured to the floor and then the closet bowl secured to the brass flange. Another method employed is to screw a brass flange into the fitting so that when it is made up the flange will come level with the floor; the closet bowl is then secured to this flange. There are a number of patented floor flanges for closet bowl connections that can be used toadvantage. Slop sinks have practically the same connections as the closets. Other fixtures such as the urinal, lavatory, and bath, can be connected with a short piece of lead wiped on a solder nipple, or the trimmings for the fixture can be had with brass having iron pipe size threads, and the connection can then be made directly with the outlet on the waste line. This is a very general way to describe the connections, but space will not allow a detailed description of these connections. It is always well to allow for short lead connections for fixtures so that the lead will give if the stack settles.
Gas is in common use in all classes of buildings today. Dwellings use it for cooking and illuminating, factories, office buildings, and public buildings for power. In some parts of the country natural gas is found. In these places it is used freely for heating fuel. The actual making of gas is something that every plumber should understand. If space permitted I would describe a gas plant with all of its by-products. However, we shall deal only with the actual installation of gas piping in buildings. Gas mains are run through the streets the same as water mains are run. Branches are taken off these mains and extended into the buildings requiring gas. The gas company generally installs the gas service pipe inside of the basement wall and places a stop cock on it free of charge. This stop that is placed on the pipe is a plug core type, the handle for turning it off is square, and a wrench is required to turn it. The square top has a lug on it. There is also a lug corresponding to it on the body of the valve. When the valve is shut off, these two lugs are together. Each lug has a hole in it large enough for a padlock ring to pass through. This gives the gas company absolute control of the gas in the building.
Setting of the Meter.—Every building that is supplied with gas has a meter that registers the amount of gas consumed. This meter is placed on the service pipe on thehouse side of the above-mentioned stop cock. This meter is furnished free of charge with a trivial charge made for setting up. The actual setting of this meter is not made until the piping throughout the building has had a thorough and satisfactory test and is found free from all leaks. The meter must be set level on a substantial bracket and in a place, if possible, where it will not require an artificial light to read its dial. The dry meter is usually used in dwellings. The interesting construction and mechanism of this meter cannot be discussed here.
Fig. 77.--Gas-meter dials.Fig. 77.—Gas-meter dials.
Fig. 77.--Gas-meter dials.Fig. 77.—Gas-meter dials.
The reading of the dials on a gas meter comes in the province of the plumber and he should be able to read them. The sketch shows the dial plate of a meter. The ordinary house meter has only three recording dials. Large meters have five or more. To read the amount of gas consumed according to the meter we will read the dials as they are indicated onFig. 77. We will call the four dials No. 1, No. 2, No. 3 and No. 4. In each of these dials a complete revolution of the index hand denotes 1,000, 10,000, 100,000 and 1,000,000, cubic feet respectively. The index hands on No. 1 and No. 3 revolve in the same direction, while No. 2 andNo. 4 revolve in the opposite direction. Two ciphers are added to the figures that are indicated on the dials and the statement of the meter will be had. To tell just how much gas has been consumed in a given time, the statement of the meter is taken at the beginning of this given time and at the end of the time. The difference in the figures indicates the number of cubic feet of gas that have been consumed. A gas cock should be placed on the house side of the meter. The dials of meter read 658,800 cubic feet. The dial having the highest number is read first No. 4 dial points to 6, this indicates that No. 3 dial has revolved 6 times. Dial No. 3 reads 5, therefore the reading of dial No. 3 and No. 4 is 65. Dial No. 2 reads 8 making the readings of the three dials 658. Dial No. 1 reads 8 making the readings of the four dials 6588 add two ciphers to this figure and 658,800 is the correct reading.
Fig. 78.Fig. 78.Fig. 79.Fig. 79.
Fig. 78.Fig. 78.
Fig. 79.Fig. 79.
Pipe and Fittings.—The pipe used in gas fitting is wrought iron or steel. In special places, rubber hose is used. Brass pipe is occasionally used to advantage. The fittings used in iron pipe gas work should be galvanized. No plain fittings should be allowed. The plain fittings very often have sand holes in them and a leak will result. Sometimes this leak does not appear until after the piping has been in use some time and the expense of replacing the fitting can only be guessed at. By using galvanized fittings, this trouble will be eliminated. All fittings used should be of the beaded type. The fitting and measurement of this work is practically the same as described under iron pipe work. To have the beginner get a clearer idea of gas-piping a building, the piping of the small building sketched will be gone over in detail and studied. One of the first important steps that a gas fitter is confronted with is the locating of the various lights and openings. With these located as shown on the plan, Figs.78,79and80, we will proceed to work out the piping. The first floor rise will be1-inch, the second floor will be 1-inch. The horizontal pipe supplying the first floor outlets will be3⁄4-inch pipe. The horizontal pipe on the second floor will be3⁄4-inch. The balance of the pipe will be3⁄8- or1⁄2-inch. At this point your attention is called to the sketch of piping, sizes, and measurements. This sketch should be studied and understood in detail. The good mechanic will employ a sketch of this kind when installing any piping. The poor mechanicwill take two or three measurements and get them out, put them in, and then get some more. This method is extremely costly and unworkmanlike. There is no reason, except the ability of the workman, why he cannot take a building like the sketch and get all the piping measurements for the job, then get them out, go to the job and put them in. The amount of time saved in this way is so great that a workman should not consider himself a full-fledged mechanic until he can get the measurements this way, and get them accurately. With a tape line, gimlet, and plumb-bob, a mechanic is fully equipped with tools to get his measurements. If the measurements are taken with a tape line, the same tape line should be used when measuring the pipe and cutting it. When laying out the piping, never allow a joist to be cut except within 6 inches of its bearing. It is good policy never to cut timber unless absolutely necessary and then only after consulting with the carpenter. When joists have to be notched they should be cut only on the top side. The pipe as it is put in place should be braced rigidly. Wherever there is an outlet pipe extending through the wall, the pipe should be braced from all sides so that when the fixture is screwed in it willbe perfectly rigid.