INSTALLATION STANDARD FOR PVC COLD WATER BUILDING SUPPLY AND YARD PIPING IAPMO IS

Transcription

1 INSTALLATION STANDARD FOR PVC COLD WATER BUILDING SUPPLY AND YARD PIPING IAPMO IS Scope.. This standard shall govern the installation of PVC piping (with solvent cemented or elastomeric gasketed joints) in cold water building supply and yard piping. (See Section 2.7 and 2.8 for allowable location and pressure.) Installation, material and inspection shall comply with the current edition of the Uniform Plumbing Code [UPC] TM published by the International Association of Plumbing and Mechanical Officials, and shall also comply with this standard. Note: The following sections of the Uniform Plumbing Code apply to PVC water piping Definition of PVC Workmanship 32.0 Protection of Piping, Materials, and Structures 33.0 Hangers and Supports 34.0 Trenching, Excavation, and Backfill Chapter 6 Water Supply and Distribution Materials (water piping) PVC Plastic Pipe and Joints Solvent Cement Joints Plastic Pipe to Other Materials Installation, Testing, Unions, and Location Chapter 4. ASTM American Society for Testing and Materials IAPMO International Association of Plumbing and Mechanical Officials UPC Uniform Plumbing Code published by IAPMO Applicable Standards. Type of PVC for Pipe and Fittings ASTM Standard PVC 20 or 220 D 784 Pipe Bell-End Poly (vinyl chloride) PVC Pipe D 2672 PVC Schedule D 785 Type of PVC for Pipe and Fittings ASTM Standard PVC Schedule D 785 PVC 60 psi (02.4 kpa) D 224 (SDR 26) PVC 200 psi (378 kpa) (SDR 2) PVC 250 psi (722.5 kpa) (SDR 7) PVC 35 psi (270.4 kpa) (SDR 3.5) Fittings Schedule (Socket) D 2466 Schedule (Socket) D 2467 Schedule (Threaded) D 2464 Solvent Cement PVC Solvent Cement D 2564 Primers PVC Primers F Product Requirements. 2. Minimum Standards. Material. Materials shall conform to the appropriate standard in Table. of the Uniform Plumbing Code. [UPC 30.] 2.2 Pipe and Fittings. Pipe and fittings are manufactured from PVC plastic. 2.3 Markings Pipe. PVC pipe markings shall be in accordance with ASTM D 785 or ASTM D 224. [UPC 30..] Fittings. PVC fitting markings shall be in accordance with ASTM D 2464 or ASTM D 2466 or ASTM D [UPC 30..] *Note: Size and material designation may be omitted on smaller fittings Solvent Cement. Solvent cement container markings shall be in accordance with ASTM D Color. Solvent cement shall not be purple in color Primers. Primer container markings shall be in accordance with ASTM F Color. Primer shall be purple Position of Markings. The identifying markings on pipe and fittings shall be visible for inspection without moving materials. 205 MINNESOTA PLUMBING CODE 83

2 2.4 Protection of Piping Storage. Unprotected pipe should not be stored in direct sunlight. The pipe shall be stored in a way to protect it from mechanical damage (slitting, puncturing, etc.). Exposure to sunlight during normal construction periods is not harmful. PVC solvent cements should be stored in a cool place, except when actually in use at the job site. The solvent cement manufacturer s specific storage recommendations should be followed. [UPC 32.0] Alignment. Pipe and fittings shall be aligned properly without strain Thermal Expansion. Pipe (except pipe with elastomeric gasketed joints) shall be snaked in the trench bottom with enough slack, at least 6 inches (52.4 mm) per 00 feet (30,4 mm), to compensate for thermal expansion and contraction before stabilizing piping. Stabilize piping by bringing it approximately to operating temperature before testing and backfilling by one of the following methods: (a) Shade backfill. Leave all joints exposed so that they can be examined during pressure test. (b) Fill with water at operating temperature. (c) Allow to stand overnight Exposed Piping. Vertical piping may extend a maximum of 24 in. (60 mm) above grade when located on the exterior of the building or structure and protected from mechanical damage to the satisfaction of the Administrative Authority. Where exposed to sunlight, the pipe shall be wrapped with at least 0.0 in. (.0 mm) of tape or otherwise protected from UV degradation. 2.5 Trenching, Cover and Backfill Trenching and Cover. Trench bottoms shall be uniformly graded and shall be of either undisturbed soil or shall consist of a layer or layers of compacted backfill so that minimum settlement will take place. [UPC 34.0] Backfill. Selected backfill shall be used. Tamp the backfill that is placed around the pipe so as to provide firm continuous support and proper compaction. Backfill at least 2 inches (305 mm) over pipes, except that joints shall be left exposed. After inspection and pressure test, complete backfill. [UPC 34.4] Elastomeric Joints. Backfill immediately after installing pipe. Note: This is to maintain equal spaces within the joints for contraction and expansion. 2.6 Joints Solvent Cement Joints Selection. Follow manufacturer s recommendations for types of solvent cement for such conditions as temperature over 00 F (38 C), humidity over 60% or use of Schedule fittings. [UPC ] Handling (to maintain effectiveness). Package solvent cement in containers no larger than quart ( liter). Keep solvent cement can closed and in the shade when not in use. Keep applicator submerged in solvent cement between applications. When solvent cement becomes thicker, THROW IT AWAY. Solvent cement shall NOT be thinned Size of Applicator. Applicator should be about one half the pipe diameter. Do not use small applicator on large pipes Primers. All solvent cement PVC joints shall be made using a listed primer in compliance with ASTM F 656 and as specified in Section of the UPC Application. Solvent cement shall be applied deliberately, but without delay (two men may be needed to make large joints). Use special care when temperature is over 00 F (38 C) or humidity is over 60% Procedure. Note: Do not take SHORT CUTS. Most failures are caused by short cuts. DON T TAKE A CHANCE Safety Requirements and Precautions General. Solvents contained in PVC plastic pipe cements are classified as airborne contaminants and flammable and combustible liquids. Precautions listed in this appendix should be followed to avoid injury to personnel and the hazard of fire Safety Precautions. Prolonged breathing of solvent vapors should be avoided. When pipe and fittings are being joined in partially enclosed areas, a ventilating device should be used in such a manner to minimize the entry of vapors into the breathing areas Solvent cements should be kept away from all sources of ignition, heat, sparks, and open flame Containers for solvent cements should be kept tightly closed except when the cement is being used All rags and other materials used for mopping up spills should be kept in a safety waste receptacle which should be emptied daily MINNESOTA PLUMBING CODE

3 Most of the solvents used in PVC pipe cements can be considered eye irritants and contact with the eye should be avoided for it may cause eye injury. Proper eye protection and the use of chemical goggles or face shields is advisable where the possibility of splashing exists in handling solvent cements. In case of eye contact, flush with plenty of water for 5 minutes and call a physician immediately Repeated contact with the skin should be avoided. Proper gloves impervious to and unaffected by the solvents should be worn when frequent contact with the skin is likely. Application of the solvents or solvent cements with rags and bare hands is not recommended. Brushes and other suitable applicators can be used effectively for applying the solvent cement, thus avoiding skin contact. In the event of excessive contact, remove contaminated clothing and wash skin with soap and water. CAUTION: Primers are toxic. Don t allow them to touch skin. Suitable gloves are advised. Step Step 2 Step 3 Step 4 Step 5 Step 6 Step 7 Step 8 Cut pipe square with hand saw and miter box, mechanical cutoff saw or tube cutter designed for plastic. Ream and chamfer pipe (to eliminate sharp edges, beads, and all burrs). Clean all dirt, moisture and grease from pipe and fitting socket. Use a clean, dry rag. Check dry fit of pipe in fitting. Pipe should enter fitting socket from 3 to 3 4 depth of socket. Soften inside socket surface by applying an aggressive primer. Soften mating outside surface of pipe to depth of socket by applying a liberal coat of the (aggressive) primer. Be sure entire surface is softened. Again coat inside socket surface with the (aggressive) primer. Then, without delay, apply solvent cement liberally to outside of pipe. Use more than enough to fill any gaps. Apply a light coat of PVC solvent cement to inside of socket using straight outward strokes (to keep excess solvent out of socket). This is also to prevent solvent cement damage to pipe. For loose fits, apply a second coat of solvent cement. Time is important at this stage. See Section Step 9 While both the inside socket surface and the outside surface of the pipe are SOFT and WET with solvent cement, forcefully bottom the pipe in the socket, giving the pipe a one-quarter turn, if possible. The pipe must go to the bottom of the socket. Step 0 Hold the joint together until tight. Step Wipe excess cement from the pipe. A properly made joint will normally show a bead around its entire perimeter. Any gaps may indicate insufficient cement or the use of light bodied cement on larger diameters where heavy bodied cement should have been used. Step 2 Do not disturb joint for the following periods: 30 minutes minimum at 60 F to 00 F (6 C to 38 C). hour minimum at F to 60 F (4 C to 6 C). 2 hours minimum at 20 F to F (-7 C to 4 C). 4 hours minimum at 0 F to 20 F (-8 C to -7 C). Handle the newly assembled joints carefully during these periods. If gaps (step ) or loose fits are encountered in the system, double these periods. Step 3 The system shall not be pressurized until the joints have cured (set) at least as long as recommended by the manufacturer. If manufacturer s recommendation is not available, the following cure times are required: Threaded Joints. Joints shall be tightened approximately 2 turn past hand tight, using a strap wrench. CAUTION: Handtight refers to number of threads to reach handtight with metal pipe. Pipe can be bottomed in small sizes of PVC by hand pressure alone. Do not overtighten Elastomeric Gasketed Joints, Procedure: Step For field cuts, cut end of pipe square with handsaw and miter 205 MINNESOTA PLUMBING CODE 85

4 Step 2 Step 3 box, mechanical saw or a tube cutter designed for plastic. Ream and bevel end of pipe (unless already done by manufacturer). If dirty, remove gasket, clean gasket and groove and replace ring. Step 4 Mark pipe in a contrasting color to indicate the proper insertion depth as recommended by the manufacturer (unless already done by manufacturer). Step 5 Apply lubricant recommended by pipe manufacturer to end of pipe. Do not apply lubricant to gasket or the groove unless otherwise specifically recommended by the manufacturer. Step 6 Insert pipe into fitting until mark on pipe is even with fitting. Note: This depth of insertion is required to properly allow for thermal expansion and contraction. During joint assembly, the previously installed length of pipe should be held so that the existing joints are not pushed together or pulled apart. DO NOT USE METAL STRAPS, CHAINS (OR THE LIKE) FOR ASSEMBLY. 2.7 Material Location. PVC piping shall be installed only outside the foundation of any building or structure or parts thereof. It shall be buried in the ground for its entire length except vertical piping may be extended above grade per Section It shall not be installed within or under any building or structure or mobile home or commercial coach or parts thereof. The term building or structure or parts thereof shall include structures such as porches and steps, whether roofed or not, roofed porte-cocheres, roofed patios, carports, covered walks, covered driveways and similar structures or appurtenances. [UPC 604.] 2.8 Installation, Testing, and Identification Deflection. Elastomeric gasketed pipe may be deflected in accordance with the manufacturer s recommendations provided that it shall not be permanently staked or blocked to maintain this deflection. [UPC 609.0] Maximum Working Pressure. Maximum working pressure shall be as follows (see chart on following page) Saddles. PVC pressure pipe saddles are limited to underground use outside the building. The branch of the saddle shall be a minimum of two pipe sizes smaller than the main. Saddles shall be installed as required by their listings Thrust Blocking. In lines with rubber gasketed joints, thrust blocks shall be installed at all: (a) Changes in direction, as at tees and bends (b) Changes in size, as at reducers (c) Stops, as at dead ends (d) Valves, where thrusts may be expected. Thrust block sizes shall be based on the maximum line pressure, pipe size and kind of soil. Refer to Table 2 for thrust at fittings for a pressure of 00 psi (689 kpa). TABLE MINIMUM CURE TIME, IN HOURS* TEST PRESSURE FOR PIPE SIZES 2 TO 4 SIZES 2 TO 3 SIZES 3 2 TO 8 (2.7 mm) (32 mm) (38 mm) (76 mm) (89 mm) (203 mm) TEMPERATURE RANGE DURING CURE PERIOD 60 F-00 F (6 C-38 C) F-60 F (4 C-6 C) 0 F- F (-2 C+4 C) UP TO psi (2.2 kpa) ABOVE TO 370 psi (2.2 TO kpa) UP TO psi (2.2 kpa) ABOVE TO 35 psi (2.2 TO kpa) UP TO psi (2.2 kpa) ABOVE TO 35 psi (2.2 TO kpa) hr 6 hr 2 hr 2 hr 6 hr 24 hr 2 hr 2 hr 4 hr 24 hr 2 hr 48 hr 8 hr 48 hr 6 hr 96 hr 48 hr 8 days * If gaps or loose fits are encountered in the system, double these cure times MINNESOTA PLUMBING CODE

5 PIPE SIZE Inches TABLE 2 THRUST AT FITTINGS IN POUNDS AT 00 psi 90º 45º 22 2º DEAD ENDS AND TEES , , ,0 PIPE SIZE mm TABLE 3 THRUST AT FITTINGS IN PASCALS AT 689 kpa OF WATER PRESSURE 90º 45º 22 2º DEAD ENDS AND TEES , , , , , , , , , , , , ,753.0, , , , ,960.0 Example for Table 2: For a pressure of 50 psi (,033.5 kpa) on a 4 inch (02 mm) tee, Table 2 indicates,620 pounds (7,209 N) for 00 psi (689 kpa). Therefore, total thrust for 50 psi (033.5 kpa) will equal 2 times 620 pounds (7,209 N) for a total thrust of 2430 pounds (0, N). To determine the bearing area of thrust blocks, refer to Table 4 for the safe bearing load of the soil and divide the total thrust by this safe bearing load. Example: TABLE 4 SAFE BEARING LOADS OF VARIOUS SOILS SAFE BEARING LOAD SOIL Lbs./sq. ft. kpa Mulch, Peat, etc. 0 0 Soft Clay Sand ,7 Sand and Gravel ,670 Sand and Gravel Cement with Clay 00 27,360 Hard Shale 0,000 68,900 Assume a 4,000 pound (7,0 N) total thrust was computed. The soil condition is sand. The required bearing area of the thrust block is 4,000 lbs. (7,0 N) divided by 2,000 lbs. (3,7 kpa) or 2 square feet (0.9 m 2 ). 2.9 Testing Rubber Gasketed Joints. Properly sized thrust blocks, either permanent or temporary, shall be installed at all required points before testing. See Section When concrete thrust blocks are installed, wait at least 24 hours before pressure testing Solvent Cement Joints. The entire system shall be purged before testing to eliminate all solvent cement vapors and air. CAUTION: Water test only Identification. A label shall be fastened to the main electrical meter panel stating, This structure has a nonmetallic water service. 2.0 Sizing Piping shall be sized in accordance with UPC Section When UPC Appendix A is applicable, use UPC Chart A 4.() (Fairly smooth). Flow velocity shall not exceed 8 fps (2.4 m/s). [UPC 60.0] This standard is a combination of sections from the previous standards IS 8 and IS 4. IS 8 was originally adopted in 968 and revised in 97, 972, 973, and 975. IS 4 was originally adopted in 972 and revised in 975. Upon adoption of this rewrite, IS 4 was deleted. Rewrite ratified by membership: 978 Revised: 9, 98, 984, 986, 989, 99, 992, 995, 2003, 2006 Appendix XI, Safety Requirements and Precautions from ASTM D 2564 Solvent Cements for Poly (Vinyl Chloride) (PVC) Plastic Pipe and Fittings is reprinted with permission from the American Society for Testing and Materials, 96 Race Street, Philadelphia, PA 903, copyright. 205 MINNESOTA PLUMBING CODE 87

6 TABLE 5 PIPE 60 psi (SDR 26) (02.4 kpa) SCHEDULE FITTINGS SIZES 2 thru 8 incl. (2.7 mm mm) 2 thru 8 incl. (2.7 mm mm) MAXIMUM WORKING PRESSURE 60 psi kpa 60 psi kpa 200 psi (SDR 2) (378 kpa) 2 thru 4 incl. (2.7 mm - 02 mm) 2 thru 8 incl. (2.7 mm mm) 200 psi kpa 200 psi kpa 250 psi (SDR 7) (722.5 kpa) 2 thru 3 incl. (2.7 mm - 76 mm) 2 thru 8 incl. (2.7 mm mm) 250 psi kpa 250 psi kpa 35 psi (SDR 3.5) (270.4 kpa) 2 thru 2 incl. (2.7 mm - 38 mm) 2 thru 4 incl. (2.7 mm - 02 mm) 35 psi kpa 35 psi kpa Schedule Schedule 2 thru 2 incl. (2.7 mm - 38 mm) 2 thru 4 incl. (5 mm - 02 mm) 5 thru 8 incl. (27 mm mm) 2 thru 2 incl. (2.7 mm - 38 mm) 2 thru 4 incl. (5mm - 02 mm) 5 thru 8 incl. (27 mm mm) 2 thru 4 incl. (2.7 mm - 02 mm) 5 thru 8 incl. (27 mm mm) 320 psi kpa 220 psi kpa 60 psi kpa 320 psi kpa 220 psi kpa 60 psi kpa 320 psi kpa 250 psi kpa MINNESOTA PLUMBING CODE

7 LOCATION OF THRUST BLOCKS (STANDARD AND METRIC COMBINED) A COMPARISON OF THRUST-BLOCK AREAS FIGURE 205 MINNESOTA PLUMBING CODE 89

8 4 sq. ft. (0.37 m 2 ) sq. ft. (.02 m 2 ) 6 Class 00 (52 mm) 0 Class 00 (254 mm) 6 sq. ft. (0.56 m 2 ) 6 sq. ft. (.49 m 2 ) 6 Class 50 (52 mm) 0 Class 50 (254 mm) FIGURE MINNESOTA PLUMBING CODE