Chapter IX: Part 9

The implements described hereafter are called “hand-tools” to distinguish them from machine-tools. _A portable tool_ is a tool or machine-tool which can be taken from place to place, for example a riveting machine.

_Tool_, the word, comes probably from toil, signifying the thing with which one toils or labors, a hammer, file or wrench; a tool never ceases to be a tool, _i.e._, something which is applied directly to the work; generally tools in machine practice cut, abrade, like a file, or strike—as a hammer; a tool is that which is brought to bear directly on the work; again, it is any implement used by a craftsman at his work; it is any instrument employed for performing, or aiding to perform, mechanical operations by means of striking, penetration, separation, abrasion, friction, etc.

Again in practical mechanics the word tool has a restrictive meaning; a single device, as a chisel, crowbar or saw, or a very simple combination of moving parts, as tongs, shears, pincers, etc. These latter for manual use, are always called tools, although embodied in the strict technical definition of machine.

Such machines as are used in shaping materials in the construction of the parts of other machines, and also many of those which perform work, such as boring, planing, riveting, etc., formerly only done by hand, and still performed manually to a greater or less extent, are nearly always called machine tools; the term, engine tool, is more in accord with general usage when referring to large and complicated machines.

_It is by his knowledge of the application of hand-tools and their practical use, that the pump attendant is judged by those around him._ The skillful mechanic, who with many others, constructs a machine, may be neglected, but one who skillfully operates the apparatus, seldom fails of due credit and reward, hence these paragraphs are intended to emphasize the importance of these more humble implements.

Fig. 610 represents _a pipe cutter_—a hand tool specially used for cutting of wrought iron, steel or brass pipe. This tool consists of a cast steel body, tapped in one end to receive the adjusting screw or handle which also serves to rotate the tool when applied to a pipe. The cutting is generally effected by a hardened cast steel cutter with cutting edges having angles of about 60° like a V thread; an enlarged form of this cutter is shown in the engraving.

Fig. 611 shows _a ratchet drill_; this is a tool in which the rotary motion of the drill is derived from a ratchet and pawl actuated by a lever or handle. There are various forms of this class of tools. This one is the “Packer ratchet.” The thread for adjusting or feeding the drill is protected from chips and dirt by a sleeve which covers the shank.

The center is of tempered tool steel as well as the ratchet and pawl. The socket is usually made square.

_In cutting larger sizes of pipes_ sometimes a special cutting-tool is introduced in place of the circular cutter to accomplish the more difficult work; in shop practice it is customary to cut the large sizes of pipe in a lathe or screwing machine.

The three tools shown on this page are designed to prepare the pipe for the reception of the threaded end of the pipe to be joined. The upper one, Fig. 612, is _a reamer_ used to enlarge a hole, or to round up one that has been drilled or cut with a chisel, to prepare it for tapping. The lower, Fig. 614, is _the tap_ which cuts the thread. The middle, Fig. 613, is a _combined drill and tap_ which is operated by a ratchet and is used to drill and tap a hole _in water pipe_, etc., at one operation.

“_Tapping_” is the process by which the thread is formed in the interior of a hole, and is done with a tap; _screwing_ is the reverse process by which the thread is formed on the outside of a cylindrical surface, as a pipe or round bar of iron.

_A tap consists of an external screw_ of the required size, formed of steel and more or less tapered, part of the thread being cut away by longitudinal grooves in order to present a series of cutting edges. By screwing into a nut in the manner of an ordinary bolt this tap forms the thread required.

_Plug-taps_ are usually made in sets of three. The first, called _the entering tap_ or taper tap, generally tapers regularly throughout its length; the second, or _intermediate tap_, sometimes tapers, but is usually cylindrical with two or three tapering threads at the end; the third, called the plug-tap or _bottoming-tap_, is always parallel, with the full thread carried to the end.

Fig. 615 shows _a crow_. This is used to hook underneath a pipe and to support and feed a ratchet drill in cutting a hole. The sliding head is fastened by a double ended gib key which secures it in any desired position. _A swivel bench vise_ is shown in Fig. 616. This tool has cast steel jaws with a wrought iron slide and is attached to the bench with a screw so that it may be turned in any position.

_A pipe vise_ is shown in Fig. 617. This is mounted on a journal bearing so that it may be clamped in any position from a horizontal to a perpendicular.

_The pipe vise is especially a bench tool_; it is designed to “grip” pipes of various sizes while they are being threaded, cut off or otherwise operated upon.

_A parallel_ or ordinary bench vise will only grip a pipe on two opposite sides, and, if tightened, the strain will easily collapse it, owing to its hollow form; but a pipe vise is so made that it presses upon four points, as the jaws or holding portions are formed V shaped, instead of parallel.

Some pipe vises are formed of two pivoted discs instead of jaws, having semicircles or recesses, which fit all diameters of pipes up to two inches, and bear on the outside of the pipe all around.

It is an improvement to have the upper portion of the vise hinged at one side, and fixed with a pin or collar at the other, as by opening the jaws it renders more convenient the removal or insertion of the pipe to be operated upon.

The upper Fig. 618 on page 342 represents an indispensable tool for cutting pipe threads by hand; one handle—of which there are two—is shown in the figure immediately beneath _the pipe stock and die_, which is the familiar name of the combination. The _guard_ in the illustration is thrown open to allow the _die_ to be removed or exchanged. Fig. 620 represents the latter; solid steel dies are commonly used, but _adjustable dies_ are made. Figs. 621 and 622 are _bushings_ to fit in the end of the stock to guide the pipe; there is one bushing for each size of pipe.

Fig. 623 shows a _nipple-holder_ which is used to hold short pieces of pipe by the thread upon one end, while the die is applied to cut a thread upon the other end. This tool is generally used in a pipe cutting machine, which is operated by power, but it can also be held in a common vise.

NOTE.—The die may be centered on the nipple described above by
_placing in the die stock_ a guide bushing that will easily ride
over the nipple holder. The thread can now be cut until the die just
touches the nipple holder, and there will be practically no blank
space between the threads on the ends. After the die has been backed
off the nipple can be removed from the holder by unscrewing the
center with a monkey wrench. _A nipple holder should be made for each
size of pipe that is cut and threaded by hand._ A piece of pipe with
a coupling on its end may be used as an improvised nipple holder.

Fig. 624 shows an extension _pipe tongs_; this tool may be adjusted to fit a number of different sizes by manipulating the thumb screw, shown in the cut.

Fig. 625 represents the _Trimo pipe wrench_. This name is an abbreviation of the word Tremont from the street in Boston of that name. It is adjusted to its work by a milled nut in the pivoted jaw; the latter is brought into position at each stroke by a leaf spring attached to the main lever. In the larger sizes the steel jaws are removable or can be detached and replaced after being repaired. The lower engraving, Fig. 626, is a _chain tongs_ with removable, tool-steel jaws. The hard scale on the piping rapidly destroys the sharp edges on these jaws so that they require frequent sharpening. The links of the chain have a peculiar hook form so that they cannot slip.

_A spanner_, shown in Fig. 627, is a special form of wrench, which circles or spans around; generally used for twisting a circular-shaped portion, provided with holes in its circumference.

_Screw or monkey-wrenches_ are those which have a movable jaw, so that the tool may be adjusted to fit any sized nut within its compass; as shown in Fig. 628. There are many designs of monkey-wrenches. The one here represented is known as the “knife-handle” on account of the identical construction of the handle of this wrench and that of a pocket knife. It is strong and the shank is extra heavy so that it is hardly possible to spring the jaws in fair use.

_An interchangeable socket wrench_ is shown in Fig. 629. The handle is much like a ratchet drill, having a pawl and ratchet wheel attached to the sockets; these are for use upon various sizes of hexagon or square heads, as represented by figures underneath the handle. Some of these socket wrenches have forms of steel for insertion into the hole in the ratchet by which different shaped and sized bolt heads and nuts may be turned without changing the main socket.

_The word wrench_ which gives this term to the tools here described is one of the strong words of the English language; wrench means, primarily, “a violent twist or turn given to something,” hence, as derived, almost any instrument that causes a twist or torsional strain comes under this heading. A wrench is a tool used by hand to turn or rotate other tools, nuts or bolts.

A wrench is specially designated according to its shape and of the jaws or openings, as an open-end box-wrench, etc. If the opening is through one end, it is termed _a single-ended wrench_; if it is in the middle, _a double-ended_ or tap-wrench. If the recess is open, it is termed _an open-ended wrench_; if closed, forming a square or hexagon opening through the metal, _a box-wrench_. A solid wrench having a notched angular recess in its end, so that any nut or bolt which will enter the jaws can be grasped, is called _an alligator-wrench_.

_The hammer_ was probably the first tool used by mankind; hammers of stone are found among the remains of antiquity, and these are still in common use among barbarous races. The hammer is made in such a variety of forms that it is almost impossible to classify it; it is named not only for the use to which it is put, but after the trade-class which uses it, as the machinist hammer, the blacksmith-hammer, etc.

The hammer is made of high-grade steel, carefully tempered head and peen; the head is usually made cylindrical with slightly rounding face; the eye of the hammer is the center opening through which the handle is inserted. The peen of a hammer is the opposite end to the face, and terminates in a rounded or wedge-shaped point.

NOTE.—In its use _the hammer should be grasped near the end of the
handle_, giving it a free arm swing, and carrying the head through
a nearly vertical plane. If the plane of the swing approaches a
horizontal the weight of the hammer will produce a twisting effort
on the fore-arm, which will be very tiresome. _The handle should be
grasped with only sufficient force to safely control the blow_.

VALVES AND COCKS.

The word _valve_ comes from the Latin—_valva_—a leaf, fold or valve of a door (as of a folding door).

A valve may act automatically so as to be _opened_ by the effort of a fluid to pass in one direction and _closed_ by its effort to pass in the other direction, as a clack valve; or it may be opened or closed by hand or mechanism, as a screw valve or a slide valve. _In the glossary_ at the beginning of this work, the word has been carefully defined and several illustrations have been given of various designs of the device which have come into general use.

Valves are of several classes.

1. _Rotary_; such as _cocks_, _faucets_, _plug throttle-valves_.

2. _Lifting_; raised clear from the seat by power beneath; such as _ball_, _conical_, _cup_, _safety_, _poppet_.

3. _Hinged_; such as _clack_, _butterfly_.

4. _Sliding_; such as the _slide_, ^D^, ^B^ and _box_.

5. _Spring_; such as _some forms of safety-valves_, Snifting and Relief valves.

6. _Inverted-cup_; such as _quicksilver valve_, _air trap_, etc.

7. _Key_; such as those of the _organ_, _flute_, etc.

Other names are derived from peculiar shape, application, mode of actuation, etc.

_A cock_ is a faucet or rotary valve usually taking its name from its peculiar use or construction, as:—

Blow-off cock,
Cylinder-cock,
Feed-cock,
Four-way cock,
Gage-cock,
Oil-cock,
Self-closing cock,
Steam-cock,
Stop-cock,
Three-way cock,
Try-cock,
Water-cock, etc.

NOTE.—The above classification is that made by E. H. Knight, Civil
and mechanical Engineer, etc., and author of Knight’s Mechanical
Dictionary. He adds: “The heart is created upon the principles
of hydraulics, and is furnished with a valve. Harvey deduced the
circulation of the blood from Aquapendente’s discovery of the _valves
in the veins_.”

As may be judged by the preceding paragraphs, giving the names derived from their mechanical and other uses of several only, of a great many varieties of valves, it were vain to attempt a complete list of these devices; it may be said however that the whole system of modern mechanism would be, almost, if not quite, a failure, if they were not used.

Hence, the student will do well to familiarize himself with the valve movements sure to be found in every combination of industrial and mechanical forces.

A few illustrations of the adaptation of valves of various designs to useful purposes now follow.—

_A combined throttle and quick closing trip valve_ is shown in Fig. 609, page 336; this is made by Schutte & Koerting Co., Philadelphia; this apparatus is designed to fill the requirements of _an emergency shut-off; the valve is balanced_ and operates as stop and throttle. The object of balancing the valve is to remove the strain from the spindle, so that its operation can be effected quickly and with the least effort. The piston above the valve is not tight fitting, and contains _a small auxiliary or pilot valve_ attached to the spindle, which opens in advance of the opening of the main valve; thus the pressure above the piston and below the valve is equalized; little effort is now required to lift the main valve, at the same time the pilot valve, E, answers the purpose of a by-pass.

The several proportions are such that a slight over-pressure is maintained above the piston to give the valve, at all times, a tendency to close. This over-pressure should be but slight, and to regulate it at will there is (besides the leak around the piston) _a separate steam admission above the piston, regulated by the plug, C_.

Depending on the fit of the piston, this plug is opened more or less, or entirely closed, when valve is first put in operation, and then locked in that position.

Ordinarily the construction of this valve demands the application of a screw-spindle to actuate it; _it is also made in angle form and can be placed with spindle upward or horizontal_. In all positions, globe, inverted and angle valves, steam must always enter above the disc, viz., in the direction of the arrows.

_The operation by lever is demanded when a valve is used as a quick emergency shut-off_, either by hand or in connection with automatic appliance of governor, electrical cut-off or auxiliary, steam, air or hydraulic cylinder.

The valve itself is of the balanced form, except that in this valve _the spindle carries at the bottom a small piston or sleeve, F_, shown in the figure. The valve is locked open by moving hand lever up till the catch on same engages with the lever, G, supported on the upright bar.

The valve being then open, steam pressure acts on the area of the piston, F, with continuous downward force, which will cause the valve to close as soon as the latch is released. Thus, by connecting the rod on the outer end of lever, G, with a hand lever, at any desired location, the operation is had without effort and promptly.

_A pressure reducing valve_ is shown in outline and a side view in Figs. 633 and 634; this is in effect a (Mason) pump pressure regulator and it is applicable for fire, tank, elevator, air and water works pumps, or any class of pumping machinery where it is necessary to maintain a constant pressure. The regulator may be quickly adjusted to any pressure desired by turning the key as shown in Fig. 633.

The especial feature of this regulator is that the pressure chamber into which the water enters is entirely removed and separate from the steam and all working parts.

The long cylinder at the bottom of the regulator is a dashpot, the piston of which is connected with the main valve of the regulator, thereby preventing sudden and violent “jumping” of the pump when the pressure suddenly changes. These valves are made in all the pipe sizes; those up to and including 2-inch of the best steam metal; the largest sizes of cast iron, lined with steam metal. _The springs are made of the finest tool steel, tempered._

The Mason Regulator Co., Boston, are to be credited with the following directions:

The regulator is placed in the steam pipe leading from the boiler
to the steam pump and as near the pump as possible. The connection
with the water system is made either from the tank or from the water
system, at some little distance from the pump. Brass pipe should be
used if possible, for this connection. The drip should be connected
to some pipe where there is no back pressure. The steam from the
boiler enters at the point marked “steam inlet from boiler,” and
thence through the passage, X, through the port, which is kept
open by the tension of the spring, 79, upon the auxiliary valve,
80. It continues down through the passage, Z, to the under side of
the differential piston, 70, and raises the valve, 16, so that the
boiler pressure is admitted to the pump through the passage marked
“steam outlet to pump.” This starts the pump, which continues in
motion until the required water pressure is obtained in the system
and acts through the connection marked “water pressure inlet” on
the diaphragm, 74. This diaphragm is raised by the excess of water
pressure, and carries with it the auxiliary valve, 80, which closes
the port for steam pressure. By the closing of this valve, the boiler
pressure is shut off through the passage, Z, from the differential
piston, 70, and the steam pressure from the boiler immediately
closes the main valve, 16, so that no more pressure is admitted to
the pump, which remains inactive until the water pressure in the
system drops below the normal joint and relieves the water pressure
in the chamber, O, which causes the auxiliary valve, 80, to open
again, and starts the pump as before described. The check valve, 71,
which is placed in the bottom of the piston, 70, allows the pressure
regulator to open easily, but stops the pump quickly. This is a great
advantage, as the pump will not start with a jump, the moment the
water drops. By changing the tension of the spring, 83, through the
key stem, 85, the amount of water pressure can be regulated.

_Mason water reducing valve._ Fig. 635 is designed to reduce the water pressure from the street water mains to a low pressure, for houses and buildings. The body or valve portion is fitted with couplings, so that it may be easily attached to a pipe. That part of the valve above the diaphragm, and which comes in contact with the water, is made of the best steam metal, thus preventing corrosion. The long spring case is made of heavy iron pipe, at the end of which is an iron bracket, suitably drilled, so that the valve may be securely bolted either to the floor or to a beam overhead. The tension of the main spring is adjusted by means of a small rod inserted in a nut at the end of the spring case. The diaphragm is very strong and will hold several times the pressure required. The working of this regulator is very simple. The water enters through the inlet coupling, 45, and passes through the chamber, 68, into the low pressure side of the regulator, the valve, 43, being held open by the tension of the spring, 53. When the low pressure has attained the desired limit, which is also felt in the diaphragm chamber through the hole which communicates with the chamber, 68, it forces down the diaphragm and seats the valve, 43. When the pressure again drops in the system, the diaphragm is forced up by the spring, 53, and the valve, 43, again opens.

_An automatic throttle valve_ for a boiler feed pump is shown perspective and outline in Figs. 636 and 637; this is a governor for the pump, controlled by the relative pressures of steam and water. It is known as _Mullin’s automatic controller_ and is made at Seattle, Wash., and has the following features:

It is simply a balance valve and differential piston; it is in a class by itself, both as to its construction and operation in regulating feed water pressure in connection with steam boilers.

The initial steam pressure being on the ends of the valve, has access, through the neck, to the full area of the piston, and will force it into a position that gives the full valve opening, where it will remain until overcome by water pressure from the pump, acting against the opposite side, which is of reduced area.

It is necessary in operating this valve to have _an excess of water pressure over the steam pressure_ in the boiler. The excess of the water pressure is obtained by the reduction of the area of the water side of the piston—thus to illustrate—if the total area were 10 square inches, and the reduction was one inch or 10 per cent., it would require that the water pressure should be 10 per cent. greater than steam pressure, to give the same thrust on the piston, then until the water has reached a pressure 10 per cent. in excess of the steam, the valve would be held open, but thereafter it is held open only wide enough to admit steam to the pump to keep up this 10 per cent. excess pressure. Should the excess pressure attempt to rise above this, it immediately forces the steam valve nearly shut, thus nipping the cause of the rise, namely, too great a piston speed.

NOTE.—“In starting the pump, ‘stand by’ until it has caught suction,
and accumulated nearly the correct water pressure, now open the
valve on the pulse, or pressure pipe to the controller and open pump
throttle wide, thus giving the controller free action.

“Suppose the boiler pressure is 100 pounds, the water pressure will
be 10 per cent. higher or 110 lbs. Carrying an even fire, with
water at second gauge, feed valves properly set, the load suddenly
increases, which pulls steam down to 99 pounds, the water does not
remain at 110 lbs. as before, but is now 10 per cent. in excess of 90
lbs. or 99 lbs., thus in place of 10 lbs. excess water pressure there
is but 9 lbs., which means there will be less water delivered through
the feed valves, which will hardly ever have to be touched.

“Next the load will lighten—steam will rise, and the excess pressure
will automatically increase, thus restoring the water used at a time
when it was most necessary to lighten the feed to temporarily favor
the fire.

“Suppose the load continues light, with good fires, steam rises to
110 pounds, the water will rise to 10 per cent. more pressure or 121
pounds, thus automatically giving more pressure to ‘feed up’ on high
steam, and store away the heat that would be wasted by radiation,
absorption, or perhaps blowing off.”

The water pressure will vary only as the steam pressure varies, always keeping the same per cent. of excess. The results are directly opposite to what would or does occur where feed water is delivered at a stated pressure. On a battery of boilers, during the cleaning of fires, the closing of feed valves on one, two or more boilers, does not affect the feed of those already set in the least, the pump will simply make less strokes necessary to properly feed the others.

The regulating is done by the feed valves at the boilers; if it is desired, all feeds may be closed, and the pressure will not rise, the pump will stop; if its plungers need packing it will be detected by the fact that the pump will creep, to keep up the required pressure. When feed valves are once regulated to admit the required amount of water, to replace the evaporation, _they may be marked_, and when in this position, they, with an even steam pressure, will always admit the same amount of water to the boilers.

It is understood that this valve is placed between the ordinary throttle valve and the pump.

_The Bordo blow-off valve_ is shown in Figs. 638 and 639; it consists of a brass or iron body which resembles the shell of a plug-cock, but with this difference, it has a sharper taper than the regular plug-cock; in this device the plug is usually made of brass—tinned on the outside. In process of making and while hot a sheath of babbitt metal or its equivalent is cast upon the plug; the metals amalgamate and practically become one casting.

The parts of valve are as follows, 1, the body, 2, the plug, 3, the packing and lifting gland, 4, the lifting cam, 5, lock-nut, 6, two brass rings of equal size, with a special gasket between them—all as shown in the engravings.

_The valve is operated_ with a wrench on the square of the plug. The lifting gland when adjusted is permanently held by a lock-nut. By releasing the lock-nut with the wrench and turning the gland to the left, the plug is lifted so that it will turn easily. When the lock-nut is moved up, the lifting cam (which couples the packing gland to the plug) can be pulled out; the gland is then free to be removed for repacking. In use the best method of handling is to open and close the valve slowly—never with a jerk.

_The tendency toward higher pressure_ steam boiler installation has made apparent the need of a blow-off, like this one described, made of strong material and correct in principle; in fact the high steam pressures now carried have almost made a revolution in boiler appliances.

The Fig. 640 represents two valves applied to the end of a blow-off pipe. The valve next to the boiler is open at all times excepting when the operating valve, next to the sewer is to be attended to for repairs, etc.

_The table below is_ intended to correspond with the letters to be seen in the illustration, Fig. 640.

TABLE.

====================================================================
Size | Diam.|Centre|Centre|Centre|Centre| Diam. | No. |Diam.|Thick.
in | of | to | to | to | to |of Bolt| of | of | of
Inches|Flange| Face |Bottom| Top |Bottom|Circle |Bolts|Bolts|Flange
+------+------+------+------+------+ | | +------
| A | B | C | D | E | | | | I
======+======+======+======+======+======+=======+=====+=====+======
1 |4-1/2 |2-1/2 |4-1/2 |4-1/2 |2-1/8 |3-1/4 | 4 | 1/2 |11/16
------+------+------+------+------+------+-------+-----+-----+------
1-1/4| 5 |2-3/4 |5-1/8 |5-1/4 |2-1/2 |3-3/4 | 4 | 1/2 | 3/4
------+------+------+------+------+------+-------+-----+-----+------
1-1/2| 6 |3-1/4 |5-7/8 | 6 |2-3/4 |4-1/2 | 4 | 5/8 |13/16
------+------+------+------+------+------+-------+-----+-----+------
2 |6-1/2 |3-3/4 | 7 |7-1/4 |3-3/8 | 5 | 4 | 5/8 | 7/8
------+------+------+------+------+------+-------+-----+-----+------
2-1/2|7-1/2 |4-1/4 |8-1/4 |8-5/8 | 4 |5-7/8 | 4 | 3/4 | 1
------+------+------+------+------+------+-------+-----+-----+------
3 |8-1/4 | 5 |9-1/2 | 10 |4-5/8 |6-5/8 | 8 | 5/8 | 1-1/8
------+------+------+------+------+------+-------+-----+-----+------

One cock of this pattern is usually employed, but to use two (as shown in the figure) is the best practice especially for high steam service.

NOTE.—It will be easily understood that the B. O. is an abbreviation;
it stands for Bordo. The makers claim for the device that, 1, it will
not stick or jam, 2, it keeps it seat under pressure, 3, it has full
pipe area in ports, 4, it is easily adjusted to take up wear and, 5,
it opens and closes with a quarter turn and with a very short wrench.

PIPES, JOINTS
AND FITTINGS

PIPES AND FITTINGS.

_A pipe_ was originally a wind instrument of music, consisting of a _tube or tubes_ of straw, reed, wood or metal; in the literature of hydraulics this wind instrument becomes “_a long tube or hollow body of wood, metal, earthenware, or the like_; especially, one used as a conductor of water, steam, gas, etc.”

_A pipe fitter_ is one who fits pipes together, or applies pipes, as to an engine or pump. A pipe fitter uses all the tools already described and in addition several others, as stretched lines, the spirit level and plumb-bob; he also uses special devices to aid in special cases; these are sometimes invented by himself and sometimes belong to “the trade-lore” transmitted in the long and varied operations of every successful shop. _A pipe fitting_ is a piece, as a coupling, a valve, etc., used for connecting lengths of pipe or as accessory to a pipe. _Joint_ comes from the word join and means the place or part where two things or parts are joined or united as a joint in a pipe. See note below.

Narrow surfaces make better and safer joints than wide ones; they are more quickly repaired with file or scraper, and they are less liable to catch dirt at the moment of making a joint. The limit of narrowness is that required to resist strains that might crush the metal and spoil the face of the joint.

Unless the joint is made metal to metal, fitting without any orifice, the jointing material is always softer than the pipes or other things to be joined. In this way the jointing need not have dead-true surfaces, but, yielding under pressure, it adapts itself to the space it has to fill. It must be dense enough and hard enough to resist all the working strains and influences that are likely to act upon it. The jointing of a steam pipe must resist the temperature of the steam, the water it carries with it, the changes of temperature when the pipe cools during intervals of work, and the strains due to the weight of the pipe, and also the internal pressure of the steam. If it expands differently from the metal in the pipe, it must be sufficiently elastic to compensate for this expansion, otherwise it will leak each time the pipes cool down.

NOTE.—In proportion as steam pressure gets higher joints are made
thinner and flanges smoother. In the past rough turning succeeded
chipping, rough filing followed with an application of the surface
plate, and finally the scraper was used to produce a dead-true
surface, which is now only cleaned and wet with heavy mineral oil to
withstand any pressure whatsoever.

The joint should be always inside the line of bolts, and if any joint material extends beyond, it would only help to support the flange in case it should spring. This, of course, indicates faulty design, for flanges ought to bear the strains of jointing without perceptible spring. Male and female flanges are best for high pressures.

A very popular joint is made with a planed or turned surface and a sheet of paper of the quality used to wrap bales of paper. This is the last survival of the millboard. Rubbed over the flange with a dirty hand and cut out with a penknife on a board, this is one of the cheapest jointings known. This paper has no lumps or grit in it, and if smeared with mineral cylinder oil it may be separated several times before it is spoiled. It is largely used on the faced joints of small engines and steam pumps. The mineral oil increases the life of the paper when exposed to high steam. Sheet asbestos is better.

_Hydraulic joints for high pressure_ require greater rigidity than those of steam, but they do not have to bear high temperatures. The jointing material may be more or less plastic, such as leather, rubber or gutta percha. It is generally inclosed in a groove in the flange, and compressed by a projection fitting the groove, so that expansion of the jointing is arrested and the space is completely filled. There is no better principle for joints than this where packing is used between flanges. At a pressure of three tons to the inch, every square sixteenth of an inch must resist a power equal to twenty-six pounds; the joint must therefore be non-porous.

_There are compounds used for making joints_ on which the plastic matter, which is subject to much change of volume between the liquid and solid state, is mixed with a neutral substance, like sand, which, combining mechanically with it, replaces from 90 to 95 per cent. of the total mass, and reduces its shrinkage to an inappreciable quantity.

Another class of joints is that into which the jointing material is poured in a liquid state. Most of those liquids, such as lead, pitch, putty, sealing-wax, beeswax, or clay, shrink when they dry or cool. Others, like _Portland cement_ and certain metallic alloys, do not change in volume. Others, again, like sulphur and plaster of Paris, increase in volume in setting. These substances all vary in their elasticity, qualities of density, hardness, and powers of resisting heat, cold and moisture. The duty of a joint must, therefore, be well considered before the material is chosen, after which the recess in which it is to lie must be carefully designed so as to firmly hold the material and with the least possible waste.

_Kerosene_, from its solvent powers, will destroy joints of rubber or of cements compounded with oils. Kerosene tanks are, therefore, rust-jointed and calked. As kerosene does not dissolve anything that is soluble in water or alcohol, kerosene casks are coated with glue to make them tight. India rubber may be used as a kerosene joint if inclosed like the hydraulic joint, and prevented from swelling. It is then unable to absorb the liquid. But leather is very much better.

_In making up a piece of piping_ in which several fittings are quite close together, each fitting is tightened separately; do not follow the common practice of making up loosely at first and then tightening all together by applying a wrench to the fitting farthest from the main connection, as this process does not insure tight joints and the intermediate fittings, nipples, etc., are subjected to an unnecessary torsional strain.

The proper arrangement of pipe connections have already been alluded to in Part One, page 222; it is a subject whose importance can scarcely be magnified for if any difficulty is experienced in making a pump work properly when first started, it will generally be found to proceed from imperfect connections, and this remains true quite to the end of the usefulness of the pump. By a careful study of the illustration above mentioned, a good degree of attention will be repaid.

Figs. 641 and 642 represent pipes which are specially intended for _mine pump columns_ or discharge pipes. They are made in sizes from six inches to thirty inches outside diameter; they are of wrought iron, lap welded and tested to a pressure of five hundred pounds to the square inch; they are fitted with cast iron or steel flanges, bolts and gaskets which face square with the center line of the pipe.

These flanges are shrunk on the pipe as shown in the figures, expanded and flared inside.

Fig. 643 represents a male and female flange joint metal to metal combined with and forming a part of the pipe; it is used for special work and conditions. Fig. 644 is the usual screwed sleeve threaded connection with right hand coupling. Fig. 645 is a much used male and female _flange union_ screwed for the reception of standard wrought iron pipe. Fig. 646 illustrates the common threaded malleable iron union and Fig. 647 the plain light _malleable iron tee_.

NOTE.—Attention of the reader is directed to that part of the
Glossary in the opening pages of Part One which relates to pipe and
fittings as being closely related to this division of the work and
which may be considered as an introduction to what is now added.

_Steam Pipe Lines._ These are constructed of cast iron or wrought iron and used for conveying a supply of steam from the boilers to engines, pumps, turbines and other machines driven by steam. Usually these lines are built up with straight pipe and “fittings.” The names of the latter are as follows: elbows; forty-fives (45°); tees; plugs; caps; reducers (or bushings); nipples; valves; unions (with ground, perishable, and flange joints); couplings (reducing and right and left); crosses; special fittings, such as elbows and tees of a nominal size reduced at some point to a smaller size to avoid the use of reducers; angle, check, and gate valves, and plug cocks; lock-nuts.

NOTE.—Cast iron was formerly entirely employed for steam pipe, but
now it is never used for high pressures.

While lead and iron pipe have taken the place of the old log pipes
of former days for carrying water and sundry purposes, there are
still uses for which wooden pipe is better adapted than any of the
metal pipes; a new kind of wire wound wooden pipe has been made. Each
length is built up of staves, wound with galvanized steel wire under
tension. The sizes are made 2 to 8 inches internal diameter. The
staves are kiln-dried, 7/8 inch to 1-1/2 inch thick. Joints are made
with a male and female socket on the small sizes, and a sleeve and
butt joint on the larger sizes, 8-inch pipe of this type, wound with
No. 4 copper wire, has been tried, where acid water rapidly destroys
ordinary pipes, with excellent results. This pipe has been tested to
500 pounds pressure, it is lighter to handle and is not so liable to
burst as cast iron.

_The proper anchoring and supporting of large steam mains is important._ It is preferable to allow the system to expand in the proper direction without stress and at the same time avoiding vibration. The illustrations will give an idea of the method used in supporting pipes and allowing for expansion. Fig. 657 shows a wall bracket upon which the rollers supporting the pipe and allowing for the expansion and contraction are attached. Fig. 655 shows a bracket with an adjustable single roll, which may be adjusted to suit the pitch of the pipe at the same time allow the pipe to expand.

_Fig. 655 shows a bracket_ with one adjustable roll designed for main steam pipes. This is an elaborate device but would be appreciated in buildings where everything is wanted to make up a strictly first class line of details.

Fig. 657 represents an extension of the same idea in which one bracket is made to carry two lines of pipe smaller than the one shown in the preceding illustration. Fig. 656 is a support made of one inch round iron and answers every purpose where all of these designs of pipe hangers permit of free expansion and contraction of the pipes.

It is bad practice to support the main steam pipes over boilers by hangers from the building as the building may settle in a different degree from the boiler hence the steam pipes are not properly supported, _i.e._, they are either strained unnecessarily by the strain upon the hangers or they are permitted to support themselves; it is better to support them by iron props underneath, made by screwing a flange upon the end of a piece of pipe of proper length and having a wrought iron crotch with thread and nut for adjustment inserted in the upper end.

The flange on the prop rests upon the boiler walls while the crotch fits the pipe and by means of the nut any desirable elevation of the steam pipe may be secured. For when the boilers settle as they will the pipes and connections all settle together.

Fig. 648 shows the common wrought iron _right-hand sleeve coupling_ and Fig. 649 a plain lock nut.

Fig. 650 shows _the bell and spigot connection_ commonly used for joining cast iron water or soil pipes, the joint being formed by pouring melted lead into the cavity inside the bell. The melted lead is prevented from escaping by damming up the opening with a turn of oakum at the bottom and fire clay at the top of the joint. After the lead cools it is calked with a calking tool. Fig. 651 is similar to Fig. 643 only the latter has plain flanges with a gasket, A, B, inserted.

Fig. 652 represents an improvement on the union shown in Fig. 646. It is known as _the Dart-union_. The improvement consists in the substitution of a ball and socket joint made of composition brass or bronze ground joint and enclosed within the malleable iron case; unions are particularly desirable for inaccessible locations where it would be next to impossible to reach the union to renew the gasket.

Fig. 653 is an extra heavy _beaded malleable iron tee_, while Fig. 654 shows a common threaded _cast iron pipe plug_.

The figures on page 366 are one half end views, divided on the center line, of brass and iron tubing; they are reduced in size, but show their relative thickness, from one eighth inch up to four inches inclusive.

The “_Standard_” sizes are shown in Figs. 663 and 664.

The “_extra strong_” are represented in Figs. 658, 661 and 662.

The _double extra strong_ is shown in Figs. 659, 660, 665 and 666.

All “tubing,” including boiler tubes, is measured by the _outside diameters_, while gas and steam pipe, including cast iron water pipe is designated by the inside diameter.

NOTE.—The best way of jointing hydraulic pipes has been the
subject of much practical experiment. A gutta percha ring has been
universally adopted as the best means of preserving the joint
watertight. Modified form of this joint is made by casting a
projection on the pipe beyond the flange, the bell and spigot being
formed on this projection. The effect is to increase the depth and
the strength of the flange, without an increase of its section at the
junction between the flange and the pipe.

Much might be said regarding duplicate pipe systems, both for and against. The general practice is coming to be that of subdividing into units, while in smaller plants the duplicate system is used. The service and conditions govern the method of piping, which should be such in every instance as to prevent a shut down due to accident in some part of the system.

All the fittings in the pipe system of a plant should be of the best quality, and the piping for high pressures should be extra heavy to withstand the test of time and usage. Water pipes, when of commercial wrought iron, should be galvanized.

In laying out a line of piping or in replacing a portion of an existing line _the measurements should be taken from center to center_ of the various fittings; the allowance for the threaded part of the pipe can be made after the center-to-center and over-all measurements have been made and before the pipe is cut. Experience teaches what to allow for the threaded part on different sizes of pipe. The accompanying engraving gives an illustration of how the measurements on a pipe system are made.

As, for example, A represents the distance, center-to-center, from
elbow to tee; B, from the starting place to center of elbow; C, the
distance, center-to-center, of the two elbows; D, from the starting
place to the center of the globe valve; E, the center of the globe
valve to the center of the tee, and F, from the center of the tee to
the center of the elbow.

G shows the center of the elbow to the center of the union; H, from
the center of the union to the center of the tee, and I, from the
center of the tee to the center of the elbow; J, from the center of
the elbow to the center of the coupling, and K, from the center of
the coupling to the final tee; all as indicated by the arrow heads
and crosses.

USEFUL NOTES

“_There are many fingers pointing to the value of a training in science, as the one thing needful to make the man, who shall rise above his fellows._”—FRANK ALLEN.

“_The motto marked upon our foreheads, written upon our door-posts, channeled in the earth, and wafted upon the waves is and must be ‘Labor is honorable and Idleness is dishonorable.’_”—CARLYLE.

“_A heavy wager has been laid
That there are tricks in every trade._”

USEFUL NOTES

RELATING TO PUMPS AND THEIR MANAGEMENT

_It happens at times_ that a pump, with the full pressure against which it is expected to work, resting upon the discharge valves, refuses to lift water for the reason that air within the pump chamber is not dislodged, but only compressed by the motion of the plunger. It is well, therefore, to arrange for running without pressure until the air is expelled and water follows. This is done by _placing a check valve in the delivery pipe, and providing a waste cock in the discharge chamber to be closed after the pump has caught water_. A stop valve is also required for shutting off the back pressure when the pump can be opened for examination of the valves.

* * *

If any difficulty is experienced in making a pump work properly when first started, it will generally be found in leaks through _imperfect connections_, or from the temporary stiffness to be expected in a new machine, or perhaps leaky valves.

* * *

If, when standing at the suction end of a centrifugal pump, looking over pump shell toward pulley, the top of shaft revolves from right to left, or against the sun, _the pump is right hand_, and if from left to right, or with the sun, _it is left hand_.

* * *

_A pump should be located in a convenient_ as well as a clean place. It should be well set upon a suitable foundation, so that it may be free from vibration or jar; this “note” applies to direct-acting, self-contained pumps, as well as to others.

* * *

The economical operation of a pump depends, to a great extent, upon the kind and condition of the packing in the stuffing-boxes and pistons, its quality, adaptability to particular requirements, and the method of placing it in the stuffing-boxes and plungers.

* * *

Almost all the stuffing-boxes on pumps are too shallow and the glands too short. To keep a rod tight under these conditions the packing must be of the proper size and quality, and it must be put in with a view to securing the greatest possible degree of elasticity, so that the rod may be kept tight with the least pressure on the packing.

* * *

To do this, it is best to select packing which will permit a number of narrow rings to be used instead of a few wide rings. The rings next to the bottom will become dry and hard before those next to the glands of the box are half worn out. If a number of narrow rings are used, the dry ones may be removed and duplicated by new ones and replacing the rest of the packing in the stuffing-box. This method economizes packing and secures a tight yet freely working rod.

* * *

When patent square packings are used, it makes less difference whether the rings are narrow or wide, because the surface in contact with the rod will be nearly continuous in either case.

* * *

When cutting packing rings, the length should be such that the ends do not come together within 1/8 inch when put into the stuffing-box, and the rings are put in to break joints, which prevents leakage through them.

When inserting this packing, the rings are put in one at a time, using a piece of hard wood to push them to the bottom of the stuffing-box and firmly against one another. The stuffing-box should be filled as full as it can be, and start the nuts on the studs by hand. Screw up the nuts with the hand and then start the pump slowly. If leakage occurs do not attempt to tighten the nut while the rod is in motion, and in all cases tighten it only enough to stop the leakage. A slight leakage at the water end is not harmful. A little cylinder oil and graphite occasionally applied to the rod will tend to keep it smooth and bright, which condition is favorable to the durability of the rod and of the packing.

* * *

When cutting rings of packing for the water piston or plunger, the rings should be 1/8 inch short, as previously described, page 372.

* * *

Packing should fit the grooves in solid pistons moderately tight, so that the packing can be pushed into the grooves with the fingers. The depth of the packing should be such that the piston will fit the bore of the water cylinder snugly when first put in. If packing of the proper depth cannot be obtained, it is better to have the grooves turned to receive standard sizes of packing and not require special sizes. Cutting hydraulic packing is a tedious job, consuming a great deal of unnecessary time.

* * *

_It takes less power to feed into the bottom of a tank than it does into the top_, on account of the weight of water in the tank. The bottom of the tank holds up all the water except the column directly over the opening of the delivery pipe, so that the additional pressure on the pump is due only to the depth of water in the tank, not to the size of the body, and it is impossible to feed into the top without increasing the height of the column fully as much. It makes no difference whether the height is due to the depth of the water inside the tank or an additional length of pipe outside.

* * *

_The duty of the air pump is solely to get rid of the water and air in the condenser._ It adds to the efficiency of the condensing apparatus, and renders its operation continuous; its valve being thrown by the action of its own piston, it must complete its stroke in length whether the piston is moving in air, water or vapor.

_Pumps should be kept clean internally and externally._ In order to keep a pump clean internally it must be inspected and oiled internally at regular intervals the same as it is externally.

* * *

When pumps fail to work properly the difficulty is generally located in one of three places, viz.: _the water end, the steam end or the suction pipe_.

* * *

The several parts of the valve gear of a single cylinder pump _should be marked when the pump works properly_, then any trouble due to the slipping of the collars or tappets can readily be remedied; if the nuts and set screws are kept tight, derangements occur only at long intervals.

* * *

The principal difficulties encountered with steam pumps are not generally due to improper steam distribution, but to wear, as may be seen; hence by inspecting pumps at regular intervals many unpleasant occurrences and accidents can be avoided.

* * *

_The steam pipe leading to a pump_ should be so arranged that the water of condensation, while the pump is idle, may not pass through the steam chest and cylinders, and wash off the lubricating oil. Drip cocks should be attached to steam pipes and all large pipes should have separators and steam traps.

* * *