Plumbing - Building Water Supply Part 2

All piping from the treatment plant to the consumer: main distribution lines, trunk lines, water mains and water see vices owned and operated by a governing body.

Sources of water have almost all become polluted and must be treated to produce water fit for human consumption.

Main distribution lines are the large water conduits that connect the treatment plant to smaller trunk lines, which further distribute the water to the mains of the system.

Water main distribute water from trunk lines to the individual water services. Water services carry water from the mains directly into the building of the consumer.

Originally, distribution systems were installed primarily to furnish protection against fires. Today, fire protection has become secondary, and the primary function of distribution systems is to deliver potable water to the consumer.

1. Loop system. 2. Gridiron system. 3. Tree system.

Large feeder mains surround many city blocks, and serve smaller cross-feed lines which are connected at each end into the main loop.

The piping is laid out in checkerboard fashion with piping usually decreasing in size as the distance increases from the source of supply.

There is a single trunk main, reducing in size with increasing distance from its source of supply; branch lines are supplied from the trunk.

Dead-end system.

The grid and loop systems provide better reliability because of their multiple paths. The grid is much more likely to permit uninterrupted service in the event of a breakdown in a part of the system, and continuous circulation helps to eliminate tastes and odors that can build up in a dead-end line.

1. treatment plant. 2. Closed reservoir. 3. Trunk lines. 4. Block by block water main grid. 5. Pump station. Location differ from the system layout.

1. Water is pumped from treatment plant to a high, closed reservoir and delivered to water main grid by gravity. 2. Pressurized system fed from a closed reservoir. 3. A gravity system fed from a high tank that is, in turn, fed by pressure from a closed reservoir, that is fed by gravity from plant.

Continuous service is the purpose. In Oder to accomplish this , reserve capacity is necessary in the form of additional storage, pumping, and distribution facilities.

They are usually valves at each intersection (4 valves on cross intersection and 3 on T, one valve on each line).

1. Deliver water under pressure to higher elevation. | 2. Introduce higher pressures into system.

1. In direct system water is pumped from the treatment plant to the distribution system. 2. Indirect system use pump to deliver water to a closed reservoir or tank for distribution.

1. Direct system use positive displacement pumps: reciprocating or rotary type. 2. Indirect system use non-positive displacement pump of the centrifugal type.

Main distribution lines generally are largest lines. Trunk lines are usually smaller than the distribution lines. Mains in most cases are smaller than the trunk lines. Whenever possible, sizes are graduated to keep down the cost of installation and maintenance.

1. Safety procedures for excavating and shoring, handling pipe, making joints, and testing. 2. Proper depth of burial. 3. Proper bedding of pipe. 4. Proper placement of rods and thrust blocks to prevent rupture to joints. 5. Thorough testing to ensure against leakage or contamination. 6. Protection to prevent corrosion. 7. Care in backfilling. 8. Chlorination of pipelines after installation to prevent pollution due to unsanitary conditions in the pipe.

Lack of experience, poor attitude or for reasons of supposed economy.

They should be sloped or shored, or both. Ditches in crumbling or sandy soil should be solid sheeted. Never work alone in a ditch. Be alert at all times; there is no such thing as a completely safe ditch.

1. Be sure lifting cables and rigging equipment are in good working condition. 2. To avoid confusion, have only one competent person giving signals and giving orders. 3. Be alert at all times. 4. Never work or stand under a hoisted load. 5. Utilize proper rigging procedures.

The pressure on a dead-end or a fitting can develop into tons of thrust.. In the event of a failure, the resultant blowout can cause extensive damage and perhaps personal injury.

Clear of fittings and dead ends.

Tt = .7854xDxDxP =?.7854x10x10x100 = 7,854 lb ~ 3.5 ton. | All blocking or testing equipment must be capable of withstanding this amount of thrust.

Clay pipe.

Concrete, steel, and some types of plastic pipe.

Usually cast iron or ductile iron for ease of tapping for water services.

Generally cast iron or ductile iron for the larger services; copper, brass, galvanized steel, and some types of plastic pipes are available for smaller services.

Bell and spigot rubber gasket joints.

1. Welded joints. 2. Flanged joints. 3. Mechanical joints.

1. Push-on joints. 2. Mechanical joints. 3. Flanged joints. 4. Caulked joints.

Improper bedding (preparation of the ditch bottom) of a pipe line during installation.

Usually includes removal of the soil to a depth well below the desired pipe elevation. The ditch is then refilled with stable, compacted material such as bank run gravel.

Contouring the ditch bottom to fit the pipe and then tamping the backfill.

Pipe clamps sometimes called friction clamps and tie rods sometimes called rodding.

A pipe clamps are placed on either side of the joint and they are tied together by means of threaded rods that pass through the clamps on either side of the joint. Washer and nuts then secure the threaded rods.

Two pipe clamps are placed on the pipe at angles f stress opposite to one another in front of the joint. Threaded rods are then inserted through the holes of the mechanical joint flanges at two locations. One rod connects to the first clamp and the other rod connects to the second clamp. The threaded rods and mechanical joint flanges are then secured by washers, nuts, and spacers.

If section are to be subjected to very high pressure or if the pipe joints must be deflected slightly to follow ground contours, continuous rodding may be required

Two rods run from flange to flange, using alternating bolt holes at each joint.

Each length of pipe can be back filled and compacted between joints on straight runs of underground piping installed horizontally prior to testing. The area around each joint or point of connection must be left exposed for visual inspection.

Restraining devices are available for both push-on and mechanical joint piping installations.

With the FIElD LOK gasket and push-on joint ductile iron TYTON pipe or fitting the joints are restrained without thrust blocks, bolts, grooves, rods,clamps or retainer glands.

Loop the gasket for insertion.

Make the loop between the locking segments to prevent damage to the rubber to metal bond.

Place the gasket into the socket with the heel of the gasket in the retainer seat of the socket.

Seat the gasket evenly around the inside of the socket with the heel of the gasket fitted snugly in the retainer seat and at or below the level of the throat of the bell socket.

Apply a thin film of TYTON JOINT lubricant to the exposed surface of the gasket that will come into contact with the entering pipe spigot end.

The outside of the cut end of pipe should be beveled about 1/4" at an angle of about 30* and the leading edge should be rounded with a coarse file or a portable grinder.

Clean the last 6" or7" of the end of the pipe. Make an assembly mark infield cut pipe at a location in accordance with the pipe size.

Apply a thin film of lubricant around the outside circumference of the spigot end for a distance of about 1".

Insert the end of the pipe into the socket until it contacts the gasket.

Assemble the joint until the inside edge of the first painted stripe is flush with the bell face.

Feeler gauge can be inserted into the socket to verify the proper installation of the joint.

To restrain field cut pipe (pipe without weld meant) inside ductile iron pipe and fittings.

1. clean the socket and the gasket. 2. Loop the gasket and place it in the socket with the rounded bulb end entering first. 3. Apply a thin film of TYTON JOINT lubricant to the exposed sur face of the gasket.

Proper tie rodding.

Kick blocks are pads of concrete mix poured behind a fitting or a dead-end for the same reason that rods are used to prevent joints from blowing out.

Not leaner than 1 part cement 2 1/2 part sand, and 5 parts stone or gravel.

A 12" 90* elbow develops 216 lb thrust at 1 psig of water pressure. Tt = 90x216 = 19,440 pounds of horizontal thrust at 90 psig.

In the event of negative pressure in an underground pipeline, contamination may enter through the leak or crack.

Hydrostatically at pressures equal to at least one and one half times the normal working pressure.

No. The extent of the damage depends on the soil and water conditions and types of piping materials. Metallic pipelines maybe subjected to corrosion. Plastic piping, although non-corrosive.

Electrochemical process in which the metal to be protected is made the cathode in a galvanic cell.

1. The impressed circuit process. | 2. Use a sacrificial anode.

Connect the positive terminal of a source of direct current to scrap iron while the negative terminal is connected to the pipeline.

The magnesium becomes the sacrificial anode because it is more active than the pipeline. The positive electricity leaves magnesium, flows through the electrolyte ( soil) to the pipelines, and returns through the wire.

The pipelines should be flushed thoroughly and then disinfected by inserting liquid chlorine compound into the system. The pipeline is then filled slowly with water and the co cent ration of chlorine checked for disinfecting strength. The full line should be allowed to stand for at least 12 hours and then be thoroughly flushed with potable water.

As residential and commercial.

1. Type of use. 2. Number of people using the water. 3. Type of fixtures. 4. Maximum demand at peak use. 5. Pressure loss. 6. Friction loss.

1. By installing a tee in the main . | 2. By tapping a main and installing a valve.

With the use of a yapping machine which strapped to the water main.

Drill a hole in the main, tap the hole, and screw in the valve (usually called a corporation cock or stop).

By strapping a saddle to the pipe. The valve is screwed into the saddle to make a water tight joint. A hole is drilled into the pipe through the valve.

By drilling through a valve that has been connected to the water main by means of a saddle or a split tapping sleeve (T).

By manifold tapping - several smaller taps joined together by means if a yoke or fittings and then be connected to the service piping.

1. Corporation cock or stop. 2. Curb cock or stop. 3. Curb box. 4. Meter and meter yoke. 5. Shutoff valve immediately inside the structure being served.

These practices include safety, bedding, protection and testing.

Swing joint following a corporation stop. | A sleeve at point of entry to the structure.

Cast iron, copper, brass, galvanized, and plastic.

1. For cast iron and ductile iron - mechanical, caulked, push-on, and flanged joints. 2. For copper pipe - flared, sweat, flanged and braced joints. 3. For brass pipe - screwed, braced and flanged joints. 4. For galvanized pipe - screwed and flanged. 5. For plastic pipe - bonded, welded, compression, solvent cement or clamped.

By the local water purveyor, usually at a fixed rate for the number of gallons or cubic feet of water used.

1. Positive displacement - register small amount of flow. | 2. Turbine and compound are used for registering large flows.

1. Positive displacement meters. | 2. Oscillating-piston and nutating- disc meters.

As water passes through the chamber, the piston or disc makes one complete cycle. Each rotation is transmuted to a recording dial by means of a gear train.

When a building requires large and constant volumes of flow with a minimum loss of line pressure.

Water entering the turbine meter is divided into two equal streams and passed through impellers. The rate of velocity is translated into gallons per minute by means of a series of gears connected to a recording dial.

In hospitals or apartment houses when rates of flow will vary greatly because of low and peak load periods.

It is a combination of a disc or oscillating piston meter and turbine meter. A compound valve closes off flow to turbine during low flow and to the disc portion during peak flow.

By means of a special device or piping arrangement called a meter yoke.

An arrangement of pipe and unions or flanges that will permit the meter to be removed without interruption of service.

A pipe nipple with washers can be installed in its place.

Yokes.

In a meter vault.

Lower weight and cost and greater ease of installation in a large service (8" and lager).

No extra space can be built into the meter assembly. The only extra space available is the thickness of two extra gaskets (about 1/4").

Disc meters, oscillating piston meters, turbine meters, turbo meters, single register compound meters.

Rotation of a spindle drive magnet. It transmit rotation through the wall of a meter to a second magnet which operates the meter register.

1. Chamber. 2. Disc. 3. Spindle. 4. Chamber magnet. 5. Second magnet. 6. Register.

1. A bronze case. 2. A sealed register. 3. Heat-treated glass. 4. Piston type measuring chamber. 5. A oscillating piston. 6. Permanent magnets. 7. A magnetic coupling. 8. Follower magnet. 9. Register reduction gearing. 10. A cylindrical strainer. 11. A built-in register retainer. 12. An interchangeable bottom plate.

1. Housing - cast iron. 2. Cover - bronze. 3. Nuts - bronze. 4. Test plug - bronze. 5. Screen - bronze. 6. Turbine cage - bronze. 7. Spindle - stainless steel. 8. Turbine wheels - hard rubber. 9. Bushing - hard rubber. 10. Adjustable bearing - agate.

1. A rotor. 2. Magnetic coupling. 3. A vertical spindle. 4. Gears. 5. The meter's register. 6. Straightening vanes. 7. A nose cone.

1. A single hermetically sealed totalizer. 2. Magnetic couplings. 3. A measuring chambers. 4. A reduction gear trains. 5. Turbine chamber. 6. A positive displacement (bypass) measuring chamber. 7. A swing action valve .

For protection against breakage because curb valve is usually shut off conterclockvice.

1. Main distribution lines. 2. Trunk lines. 3. Water mains. 4. Water service.

The piping within a building which conveys water from the water service pipe to the point of use .

1. Provides an adequate supply of water. 2. Provides necessary safeguard to protect the system from contamination from both inside and out side the building. 3. Maintains suitable pressure for usage demands in the building. 4. Is quiet and relatively maintenance free. 5. Supplies adequate amounts of water to the hot water generation system.

1. Design. 2. Layout. 3. Installation.

Success will depend on how well the basic principles are understood and applied to meet the needs of a particular job.

Because of wide variations in responsibilities: a very carefully designed system to install, including drawing and specifications, or no information other than location of plumbing fixtures.

1. The architect allocates the space or location of its components. 2. A mechanical or civil engineer does the actual piping arrangement.