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1. It is recommended that no dry hydrants be constructed of less than 6" piping and fittings.
2. No piping or fittings of less than schedule 40 should be considered.
3. All piping or fittings exposed to sunlight should be primed and painted.
4. A minimum number of 45° or 90° elbows, preferably two, are suggested to be used in the total system.
5. All connections should be cleaned and properly cemented so as to have all connections airtight.
6. The strainer is formed in the end of the pipe by drilling 1,140 3/8" chamfered holes along piping. One half the radius should be reserved on the pipe to eventually be installed on top to reduce the possibility of whirlpool during drought periods.

Installation is Made Easy by Some Simple Preplanning

1. Consider average water level at piping entry location.
2. Lift in excess of 15' needs to be avoided (22' maximum). This is measured from surface of water to centre of pumper suction on apparatus.
3. It is recommended that a backhoe or similar ditching equipment be utilized to excavate entire ditch to a horizontal elevation 3' below water level.
4. The ditch should be excavated beginning at the furthest point away from the water. The ditch would then be flooded, after a reasonable level has been maintained throughout.
5. The horizontal and vertical portion should be assembled and lowered in one piece, as ditch should now have water its entire length.
6. Back-filling should begin at point of vertical piping. It is suggested that the vertical pipe be tamped to assure rigid support with surrounding soil.
7. The ditch water is automatically forced back to the water source as back-filling is completed. This should be firmly packed so as not to have low areas occur at a later date, due to the settling of the soil.
8. At this point it is necessary to have personnel enter the water and place permanent supports underneath pipe out in the water. The support should be of rugged design and prevent piping from coming in contact with bottom of water source. The supports should be 1" pipe or tubing.
9. The vertical portion can now be cut approximately 12" above that final grade.
10. The elbow with threaded adapter can now be attached so as to select the most desirable position.

The Dry Hydrant is Now Ready for Use

1. Attach pumper hard hose using 4½" x available hose adapter. It is recommended that a department shall begin the procedure using two lengths of hard hose, so as to achieve initial apparatus hookup with ease.
2. The Dry Hydrant should be initially back-flushed, simply by opening pump to tank valve, allowing booster tank water to force out any silt or mud which has been trapped in pipe during installation. You should observe turbulence on surface immediately above capped pipe in water. Close tank valve; you are now ready to draft.
3. Close all discharge openings on apparatus, except suction inlet attached to Dry Hydrant. Engage priming device and observe discharge gauge and primer noise. Draft can usually be obtained in 20 seconds or less.
4. Slowly open a discharge opening and raise engine's RPM.
5. If Dry Hydrant has not been installed an excessive distance from the water, a source of flow of 600 to 1000 gpm or more can be produced (NOTE: Check on FL in 6" piping to ensure a minimum of 600 gpm).
6. Two lines can be extended from a pumper to fill tankers simultaneously creating a resupply water point.

1. It is suggested that a record of inspection be maintained with a separate card for each Dry Hydrant.
2. Initial rated capacity flow should be recorded with each installation.
3. Dry lubricant can be used to reduce grit on hydrant threads.
4. The Dry Hydrant Cap is available in the same non-corrosive alloy as the 4½" adapter. It should be secured to Dry Hydrant to discourage vandalism.

Some Final Suggestions

General Installation Recommendations

1. Handling
   Compared to steel, iron or copper pipe, PVC pipe and fittings have a lower impact resistance (especially at low temperatures). Care should be exercised during transportation and installation of PVC.
2. Solvent Cement Welding
   This method of joining is very simple and reliable if it is followed correctly, but any deviations from the recommended basic steps may reduce the strength and integrity of the joint. The procedures for preparation, insertion, and curing should be followed very carefully.
3. Expansion and Contraction
   The coefficient of linear expansion of PVC pipe is greater than that of metallic piping, therefore take this factor into consideration when designing and installing a PVC piping system.
4. Trench Preparation
   When laying PVC pipe below the ground, care should be taken to remove all rocks, boards, bottles and other debris from the trench. Smaller diameters of pipe should be snaked in the trench to allow for expansion and contraction. If solvent cement welding is used as the method for joining, snaking, pressure testing, and pipe movement should not be done until after the joints have been given sufficient time to dry.
5. Temperature/Pressure
   PVC pipe cannot be used where temperatures exceed 140°F. The working pressure of PVC pipe, fittings, and valves varies with changes in temperature. Before putting a piping system into service, the maximum working temperature and the maximum working pressure should be verified.

Rules & Guidelines for Solvent Welding of PVC Pipe & Fittings

1. Make sure the solvent cement you are planning to use is designed for the specific application you are attempting.
2. Know the physical and chemical characteristics and limitations of PVC piping materials that you are about to use.
3. Know the reputation of your manufacturer and their products.
4. Know your own qualifications or those of your contractor. The solvent welding technique of joining PVC pipe is a specialized skill just as any other pipe fitting technique.
5. Closely supervise the installation and check the finished job before start-up.
6. Contact WFR Wholesale Fire & Rescue, or competent consulting agency if you have any questions about the application or installation of PVC pipe.
7. Take the time and effort to do a professional job. Shortcuts will only cause you problems and delays in start-up. By far, the majority of failures in PVC piping systems are the result of shortcuts and/or improper joining techniques.

B. Tools & Materials Needed

1. Cutting Device--Saw or pipe cutter
2. Deburring Tool or knife
3. Brush--Pure Bristle
4. Rag--Cotton (not synthetic)
5. Solvent Cement--PVC for PVC Components of the proper type and viscosity.
6. Containers--Metal or glass to hold primer. Select the type of PVC materials to be used on the basis of their application with respect to chemical resistance, pressure rating, temperature characteristics, etc.
7. Primer--It is recommended that Tetrahydrofurance (THF) be used to prepare the surfaces of pipe and fittings for solvent welding. Do not use water, rats, gasoline, sandpaper or any other substitutes for cleaning PVC surfaces.
8. Cement--The cement should be a bodied cement of approximately 800 to 1000 centipoise viscosity containing 10-20% (by weight) virgin PVC material solvated with Tetrahydrofuran (THF). Small quantities of dimethyl formamide (DMF) may be included to act as a retarding agent to extend curing time. Select the proper cement. Schedule 40 cement should be used for Schedule 40 and SDR pipe sizes 2" diameter or less. For Schedule 40 and SDR over 2" and all sizes of Schedule 80 pipe, Schedule 80 cement is recommended. Never use all-purpose cements, commercial glues and adhesives or ABS cement to join PVC pipe and fittings.
9. Applicators--Select a suitable pure bristle type paint brush. Avoid using a synthetic brush such as nylon that will be dissolved by the primer and cement. Use a proper width brush or roller to apply the primer and cement (3-5" for 6" pipe). Speedy application of cement is important due to its fast drying characteristics.

C. Making the Joint

1. Cutting
   Pipe must be squarely cut to allow for the proper interfacing of the pipe end and the fitting socket bottom. This can be accomplished with a miter box saw or wheel type cutter. Wheel type cutters are not generally recommended for larger diameters since they tend to flare the corner of the pipe end if this type of cutter is used, the flare on the end must be completely removed.
2. Deburring
   Use a knife, plastic pipe deburring tool, or file to remove burrs from the end of teh pipe. Be sure to remove all burrs from around the inside as well as the outside of the pipe. A slight chamfer (bevel) of about 10° to 15° should be added to the end to permit easier insertion of the pipe into the fitting.
3. Inspection, Cleaning, Priming
   Visually inspect the inside of the pipe and fittings sockets and remove all dirt, grease or moisture with a clean dry rag. Check for possible damage such as splits or cracks and replace if necessary. Apply primer to the surface of the pipe and fitting socket with a natural bristle brush. This process softens and prepares the PVC for the solvent cementing step. Move quickly and without hesitation to the cementing procedure.
4. Application of Solvent Cement
   Apply the solvent cement evenly and quickly around the outside of the pipe at a width a little greater than the depth of the fitting socket. Apply a light coat of cement evenly around the inside of the fitting socket. NOTE: Cans of cement and primer should be closed at all times when not in use to prevent evaporation of chemicals and hardening of cement.
5. Joint Assembly
   Working quickly, insert the pipe into the fitting socket bottom and give the pipe or fitting a ¼" turn to evenly distribute the cement. a good joint will have sufficient cement to make a fillet all the way around the outside of the fitting hub. The fitting will have a tendency to slide back on the pipe while the cement is wet, so hold the joint tightly together for about 15 seconds. For pipe sizes over 4" it may be necessary to hold the joint together for up to 3 minutes. NOTE: Always wait at least 24 hours before pressure testing a piping system to allow cemented joints to cure properly. For colder temperatures, it may be necessary to wait a longer period of time.
6. Cleanup & Joint Movement
   Remove all excess cement from around the pipe and fitting with a dry cotton rag. This must be done while the cement is still soft. The joint should not be disturbed immediately after the cementing procedure and sufficient time should be allowed for proper curing of the joint. Exact drying time is difficult to predict because it depends on variables such as temperature, humidity, and cement integrity.

D. Helpful Hints

1. Work quickly and carefully.
2. Use liberal amounts of fresh cement.
3. Do not attempt cementing in the rain or in the presence of moisture.
4. Do not cement when the temperature is below 40°F or above 90°F under direct sunlight.
5. Do not take shortcuts or bypass recommended steps.

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