For domestic water and chilled water applications Texas A&M University requires minimum of SDR11 and meeting the following minimum specifications:

Transcription

1 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES Design Standards High Density Polyethylene (HDPE) Piping Installations Texas A&M University has chosen HDPE pipe as the Campus standard for sanitary collection lines, domestic water lines and chilled water lines. This necessitates the following changes in Facilities Planning & Construction Facility Design Guidelines. Domestic Water and Chilled Water Applications For domestic water and chilled water applications Texas A&M University requires minimum of SDR11 and meeting the following minimum specifications: 1.0 MATERIALS 1.1 The pipe and fittings shall be made Extra High Molecular Weight (EHMW) high-density polyethylene with a standard thermoplastic material designation code of PE3608 and having a cell classification of C per ASTM D Materials used to manufacture pipe and fittings shall be listed under the Manufacturer s name in the Plastics Pipe Institute (PPI) TR-4, PPI Listing of Hydrostatic Design Basis (HDB), Strength Design Basis (SDB), Pressure Design Basis (PDB) and Minimum Required Strength (MRS) Ratings for Thermoplastic Piping Materials or Pipe. The Manufacturer shall supply a product with a standard grade HDB rating of 1600 psi (minimum) at 73 o F and 800 psi (minimum) for 140 o F. Upon request, the Manufacturer shall supply certification that the materials used to manufacture the pipe and fittings meet the above requirements. 1.3 All materials, which come in contact with water, including lubricants, shall be evaluated, tested and certified for conformance with ANSI/NSF Standard The materials shall meet the following nominal physical property requirements: Page 1 October 3, 2012

2 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES Property TEST METHOD (1) NOMINAL VALUE Material Designation PPI/ASTM PE3608 Cell Classification D C Density, Natural D gm/cc Density, Black D gm/cc Melt Index (190 C/2.16 kg) D gm/10min Flow Rate (190 C/21.6 kg) D gm/10 min Tensile Ultimate D638 5,000 psi Tensile Yield D638 3,500 psi Ultimate Elongation D638 >800% Flexural Modulus, 2% Secant D ,000 psi Environmental Stress Crack Resistance (ESCR) F, Condition C 0 D1693 >10,000 hrs. PENT F1473 >100 hrs. Brittleness Temperature D746 <-180 F Hardness, Shore D D Vicat Softening Temperature D F Izod Impact Strength, Notched D256 7 ft-lb /in f Modulus of Elasticity (short term) D ,000 psi Modulus of Elasticity (long term) D638 30,000 psi Thermal Expansion Coefficient D x 10-4 in/in/ F Average Molecular Weight GPC 330,000 PPI Hydrostatic Design Basis: (As listed in PPI TR-4) D2837 1, F F (1) Test procedures are ASTM unless otherwise specified. (PPI = Plastics Pipe Institute, and GPC = Gel Permeation Chromatography.) 2.0 POLYETHYLENE PIPE AND FITTINGS 2.1 Pipe and tubing furnished under this specification shall be manufactured from compounds in compliance with Section 1.0 above. The dimensional and performance characteristics shall conform to the requirements of the most current version of AWWA C-901 (1/2 through 3 ) or C-906 (4 through 65 ). Each lot of material shall be tested for melt index, density and % carbon. Upon request, the Manufacturer shall furnish test data. 2.2 Polyethylene fabricated fittings shall be manufactured from polyethylene pipe, sheet stock or molded fittings meeting the material requirements of this specification and all appropriate requirements of AWWA C-901 or AWWA C-906. Page 2 October 3, 2012

3 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES 2.3 Pipe shall be pressure rated using the certified HDB from Section 1.2 and shall be determined in accordance with the following formula: Where DR = Dimension Ratio = D/t P = Internal pressure, psi S = Long term hydrostatic strength, psi (1,600) D = Actual outside diameter, inches t = Minimum wall thickness, inches DF = Design Factor, dimensionless (0.5 for 73.4ºF) The Pressure Class (PC) of the polyethylene pipe and fittings shall be specified on the basis of the Working Pressure Rating (WPR) of the water system as defined in AWWA C-906. Recurring pressure surges (RS) are those that occur frequently and are inherent in the design and operation of the system such as normal pump startup or shutdown and normal valve opening and closing. Occasional pressure surges (OS) are those that occur infrequently and are usually the result of a malfunction such as pump seize-up, valve stem or pressure relief valve failure. The WPR shall be the lesser of the following: (a) WPR = PC (b) WPR = 1.5PC RS (c) WPR = 2.0PC OS The pipe s DR and WPR shall be as specified by the project design engineer. The WPR as determined above must be equal to or greater than the working pressure of the system. 2.4 Polyethylene fittings, including custom fabrications, shall have the same internal pressure rating as the mating pipe. At the point of fusion, the wall thickness and outside diameter of the fitting shall be in accordance with AWWA C-901 or AWWA C-906 for the same pipe size. 2.5 The pipe Manufacturer s Quality system shall be certified to be in accordance with ISO 9001:2000. Page 3 October 3, 2012

4 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES 3.0 JOINING 3.1 HEAT FUSION Pipe and fittings shall be joined by one of the following types of thermal fusion per the Manufacturer s recommended procedures: Butt fusion, Saddle fusion or Socket fusion Upon request, the Manufacturer shall provide fusion training by authorized personnel or an authorized Representative. The Contractor shall be responsible for ensuring that personnel have received proper training per the Manufacturer s recommended procedure. Records of training shall be maintained by the Contractor and should not exceed 12 months from date of construction Butt fusions performed between pipe ends or pipe ends and fitting outlets shall be within the following allowable wall mismatches: a. 2 DR difference for pipe and fitting diameters 6 IPS and smaller. b. 1 DR difference for above 6 through 18. c. No difference for diameters above 18. The difference in DR s is determined from the following DR values: 7.3, 9, 11, 13.5, 17, 21, 26 and OTHER METHODS OF JOINING Polyethylene pipe and fittings may be joined together or to other materials through the use of electrofusion fittings, flange adapters with back-up rings, mechanical couplings designed for connecting polyethylene pipe and fittings to itself or to another material, or MJ adapters. The Manufacturer of the joining device shall be consulted for proper installation procedures. Page 4 October 3, 2012

5 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES 4.0 MARKING 4.1 Pipe and tubing shall be permanently marked in accordance with all applicable standards per this specification. Marking shall be heat stamped indent print and shall remain legible under normal handling and installation practices. 4.2 Fittings shall be marked on the body or hub. Marking shall be in accordance with the applicable standard depending upon the fitting type. Mechanical fittings shall be marked with size, body material designation code, pressure rating and the Manufacturer s name or trademark. 5.0 WORKMANSHIP 5.1 Pipe, tubing and fittings shall be homogenous throughout, and free of visible cracks, holes, foreign inclusions, blisters, dents or other injurious defects. The pipe, tubing and fittings shall be as uniform as commercially practicable in color, opacity, density and other physical properties. 6.0 TESTING 6.1 The Contractor shall be responsible for field set-up and performance of the fusion equipment and the fusion procedure used by the operator. Upon request, the Contractor shall verify the fusion quality by making and testing per the Manufacturer s recommended qualification procedure. The Contractor shall be responsible for the necessary adjustments to the set-up, equipment, operation and fusion procedure. Fusions that fail the qualification procedure shall be remade. 6.2 Hydrostatic testing shall be conducted in accordance with the Manufacturer s recommended testing procedures. 6.3 Low pressure pneumatic testing may be conducted on gravity sewer lines in accordance with ASTM F1417. Other methods of pneumatic testing are not recommended. Page 5 October 3, 2012

6 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES 7.0 THIRD PARTY CERTIFICATION 7.1 The performance requirements of the pipe and fittings shall comply with the most current version of AWWA C-901 or AWWA C-906. The Manufacturer shall be listed with NSF- 61 certification and include the third party certification within the print line of the product. Installation Installation of HDPE SDR11 Pipe shall be in accordance with AWWA M55 (Chapter 8). Notes: (1) Minimum compaction shall be to 85% Standard Proctor Density unless under a where a minimum compaction shall be to 95% Standard Proctor Density. roadway (2) Due to the potential for ring buckling of empty pipe during roadway construction installation must have a minimum cover of 1.5 feet for pipe sizes up to 18-inches and 2 feet of cover from pipe sizes 18 to 24-inches. Refer to Vertical Soil Pressure Calculations (Appendix A attached). (3) For chilled water applications fill material around pipe shall be a material such as DriTherm, Gilsulate or equivalent type material that will provide both insulating characteristics, support the pipe segment and be compactable to the desired conditions. Refer to HDPE SDR11 Heat Loss/Gain Calculation Table (Appendix B attached). Sanitary Collection Applications For sanitary collection applications Texas A&M University believes that HDPE has advantages in given situations that make it more suitable product that traditional materials. Situations such mall areas, heavy traffic areas, areas covered by decorative pavers, masonry or concrete or under roadways are examples of such applications. Texas A&M recommends a minimum of SDR17 and meeting the following minimum specifications for these applications: 1.0 MATERIALS 1.1 The pipe and fittings shall be made using Extra High Molecular Weight (EHMW) highdensity polyethylene with a standard thermoplastic material designation code of PE3608 and having a cell classification of C, D or E per ASTM D3350. Page 6 October 3, 2012

7 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES 1.2 The Manufacturer shall provide a product supplying a minimum Hydrostatic Design Basis (HDB) of 1,600 psi at 73.4 F. The stress regression testing shall have been performed in accordance with ASTM D2837. Upon request, the Manufacturer shall supply certification that the materials used to manufacture the pipe and fittings meet the above requirements. 1.3 The materials shall meet the following nominal physical property requirements: PROPERTY TEST METHOD (1) NOMINAL VALUE Material Designation PPI/ASTM PE3608 Cell Classification D C Density, Natural D gm/cc Density, Black D gm/cc Melt Index (190 C/2.16 kg) D gm/10min Flow Rate (190 C/21.6 kg) D gm/10 min Tensile Ultimate D638 5,000 psi Tensile Yield D638 3,500 psi Ultimate Elongation D638 >800% Flexural Modulus, 2% Secant D ,000 psi Environmental Stress Crack Resistance (ESCR) F, Condition C 0 D1693 >10,000 hrs. PENT F1473 >100 hrs. Brittleness Temperature D746 <-180 F Hardness, Shore D D Vicat Softening Temperature D F Izod Impact Strength, Notched D256 7 ft-lb /in f Modulus of Elasticity (short term) D ,000 psi Modulus of Elasticity (long term) D638 30,000 psi Thermal Expansion Coefficient D x 10-4 in/in/ F Average Molecular Weight GPC 330,000 PPI Hydrostatic Design Basis: (As listed in PPI TR-4) D2837 1, F F (1) Test procedures are ASTM unless otherwise specified. (PPI = Plastics Pipe Institute, and GPC = Gel Permeation Chromatography.) 2.0 POLYETHYLENE PIPE AND FITTINGS 2.1 Pipe and tubing furnished under this specification shall be manufactured from compounds in compliance with Section 1.0 above. The dimensional and performance characteristics shall conform to the requirements of ASTM F714 for sizes 4 IPS and larger and to ASTM D3035 for sizes smaller than 4 IPS. Each lot of material shall be tested for melt index, density and % carbon. Upon request, the Manufacturer shall furnish test data. Page 7 October 3, 2012

8 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES 2.2 Polyethylene fabricated fittings shall be manufactured from polyethylene pipe, sheet stock or molded fittings meeting the material requirements of this specification. 2.3 Pipe shall be pressure rated using the HDB from Section 1.2 and shall be determined in accordance with the following formula: Where DR = Dimension Ratio = D/t P = Internal pressure, psi S = Long term hydrostatic strength, psi (1,600) D = Actual outside diameter, inches t = Minimum wall thickness, inches DF = Design Factor, dimensionless (0.5 for 73.4 F) 2.4 Polyethylene fittings, including custom fabrications, shall have the same internal pressure rating as the mating pipe. At the point of fusion, the wall thickness and outside diameter of the fitting shall be in accordance with ASTM F714 or D3035 for the same pipe size. 2.5 The pipe Manufacturer s Quality system shall be certified to be in accordance with ISO 9001: JOINING 3.1 HEAT FUSION Pipe and fittings shall be joined by one of the following types of thermal fusion per the Manufacturer s recommended procedures: Butt fusion, Saddle fusion or Socket fusion Upon request, the Manufacturer shall provide fusion training by authorized personnel or an authorized Representative. The Contractor shall be responsible for ensuring that personnel have received proper training per the Manufacturer s recommended procedure. Page 8 October 3, 2012

9 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES Butt fusions performed between pipe ends or pipe ends and fitting outlets shall be within the following allowable wall mismatches: a. 2 DR difference for pipe and fitting diameters 6 IPS and smaller. b. 1 DR difference for above 6 through 18. c. No difference for diameters above 18. The difference in DR s is determined from the following DR values: 7.3, 9, 11, 13.5, 17, 21, 26 and OTHER METHODS OF JOINING Polyethylene pipe and fittings may be joined together or to other materials through the use of electrofusion fittings, flange adapters with back-up rings, mechanical couplings designed for connecting polyethylene pipe and fittings to itself or to another material, or MJ adapters. The Manufacturer of the joining device shall be consulted for proper installation procedures. 4.0 MARKING 4.1 Pipe and tubing shall be permanently marked in accordance with all applicable standards per this specification. Marking shall be heat stamped indent print and shall remain legible under normal handling and installation practices. 4.2 Fittings shall be marked on the body or hub. Marking shall be in accordance with the applicable standard depending upon the fitting type. Mechanical fittings shall be marked with size, body material designation code, pressure rating and the Manufacturer s name or trademark. 5.0 WORKMANSHIP 5.1 Pipe, tubing and fittings shall be homogenous throughout, and free of visible cracks, holes, foreign inclusions, blisters, dents or other injurious defects. The pipe, tubing and fittings shall be as uniform as commercially practicable in color, opacity, density and other physical properties. Page 9 October 3, 2012

10 DIVISION OF ADMINISTRATION UTILITIES & ENERGY SERVICES 6.0 TESTING 6.1 The Contractor shall be responsible for field set-up and performance of the fusion equipment and the fusion procedure used by the operator. Upon request, the Contractor shall verify the fusion quality by making and testing per the Manufacturer s recommended qualification procedure. The Contractor shall be responsible for the necessary adjustments to the set-up, equipment, operation and fusion procedure. Fusions that fail the qualification procedure shall be remade. 6.2 Hydrostatic testing shall be conducted in accordance with the Manufacturer s recommended testing procedures. 6.3 Low pressure pneumatic testing may be conducted on gravity sewer lines in accordance with ASTM F1417. Other methods of pneumatic testing are not recommended. 7.0 THIRD PARTY CERTIFICATION 7.1 This section shall apply when the application references high-density polyethylene, EHMW, PE3608 suitable for potable water. The product shall be manufactured per AWWA C- 901 (1/2 through 3 ) or AWWA C-906 (4 through 63 ). The Manufacturer shall be listed with NSF-61 certification and include the third party certification within the printline of the product. Installation Installation of HDPE SDR11 Pipe shall be in accordance with AWWA M55 (Chapter 8). Notes: (1) Minimum compaction shall be to 85% Standard Proctor Density unless under a roadway where a minimum compaction shall be to 95% Standard Proctor Density. (2) Due to the potential for ring buckling of empty pipe during roadway construction installation must have a minimum cover of 4 feet for pipe sizes up to 24-inches. Refer to Vertical Soil Pressure Calculations (Appendix A attached). Page 10 October 3, 2012

11 APPENDIX A VERTICAL SOIL PRESSURE CALCULATIONS

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17 APPENDIX B HEAT LOSS/GAIN CALCULATIONS

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20 HDPE SDR11 Heat Loss / Gain Calculation Summary Nominal Pipe Diameter Depth = 1 ft Depth = 2 ft Depth = 3 ft Depth = 4 ft Depth = 5 ft Depth = 6 ft (in) No Insulation Wash Sand Gilsulate No Insulation Wash Sand Gilsulate No Insulation Wash Sand Gilsulate No Insulation Wash Sand Gilsulate No Insulation Wash Sand Gilsulate No Insulation Wash Sand Gilsulate 4-4, , , , , ,405-1, , , , , ,938-1, ,771-1, , , , , ,137-1, ,038-1, , , , , ,288-1, ,253-1, , , , , ,413-1, ,546-1, , , , , ,592-1, ,701-1, , , , , ,691-1, ,839-1, , , , , ,783-1, ,079-2, , , , , ,951-1, (-) Negative Q value indicates a heat gain Assumptions/Exclusions: 1. Assumed the chilled water is a constant 42 F. 2. Assumed moisture will migrate toward a chilled pipe, therefore using a thermal conductivity value of 1.25 BTU/hr-ft- F for chilled water systems in the absence of any site-specific soil data as stated in 2004 ASHRAE HVAC Systems & Equipment Handbook, Chapter Assumed the annual soil temperature is 60 F. 4. Assumed soil moisture content is greater than 20 percent (worst case). 5. Assumed wash sand and gilsulate envelopes are 1 foot on all sides of the chilled water pipe. 6. Thermal conductivity of the HDPE pipe was 3.2 BTU-in/hr-ft^2-F defined in Piping Handbook Seventh Edition. Heat Loss / Gain per 100 ft. (BTU/hr)

21 JOB NO.: PAGE NO.: 1 COMPUTED BY: A. Welch-Castle DATE: 8/10/09 SUBJECT: HDPE SDR11 CHECKED BY: J. Cabrera DATE: 8/19/09 Heat loss Calculations with No Insulation APPROVED BY: DATE: SHEET NO. 1 of 1 Chilled Water Temperatures Depth (ranges) Soil Temperature Soil Thermal Conductivity=k soil Pipe Thermal Conductivity=k pipe 42 F 1 to 6 ft 60 F 1.25 BTU/hr-ft- F BTU/hr-ft- F Nominal Pipe Diameter Inside Diameter Outside Diameter Inside Radius Outside Radius Depth (ft) D i D o r i r o (in) (in) (in) (ft) (ft) d/r o R soil R pipe R total Q BTU*100 ft d/r o R soil R pipe R total Q BTU*100 ft d/r o R soil R pipe R total Q BTU*100 ft d/r o R soil R pipe R total Q BTU*100 ft d/r o R soil R pipe R total Q BTU*100 ft d/r o R soil R pipe R total Q BTU*100 ft , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,951 (-) Negative Q value indicates a heat gain Assumptions/Exclusions: 1. Assumed the chilled water is a constant 42 F. 2. Assumed moisture will migrate toward a chilled pipe, use a thermal conductivity value of 1.25 BTU/hr-ft- F for chilled water systems in the absence of any site-specific soil data as stated in 2004 ASHRAE Systems & Equipment Handbook, Chapter Assumed the annual soil temperature is 60 F. 4. Assumed soil moisture content is greater than 20 percent (worst case) 5. Depth measured to top of pipe. Equations: Thermal Resistance of pipe material, h-ft- o F/Btu: Thermal Resistance of soil, h-ft- o F/Btu: Rate of Heat Transfer, Btu/h-ft:

22 JOB NO.: PAGE NO.: 1 COMPUTED BY: A. Welch-Castle DATE: 8/10/09 SUBJECT: HDPE SDR11 CHECKED BY: J.Cabrera DATE: 8/19/09 Heat loss Calculations with Washed Sand APPROVED BY: DATE: SHEET NO. 1 of 1 Chilled Water Temperatures Depth (ranges) Soil Temperature Washed Sand Thermal Conductivity=k sand Soil Thermal Conductivity=k soil Pipe Thermal Conductivity=k pipe 42 F 1 to 6 ft 60 F 0.2 BTU/hr-ft- F 1.25 BTU/hr-ft- F BTU/hr-ft- F Nominal Pipe Diameter Inside Outside Inside Outside Diameter Diameter Radius Radius D i D o r i r o Equivalent Diameter of Equivalent Radius of Depth (ft) Washed Sand Envelope D e Wash Sand Envelope r e (in) (in) (in) (ft) (ft) (in) (ft) d/r e R soil R pipe R sand R total Q BTU*100 ft d/r e R soil R pipe R sand R total Q BTU*100 ft d/r e R soil R pipe R sand R total Q BTU*100 ft d/r e R soil R pipe R sand R total Q BTU*100 ft d/r e R soil R pipe R sand R total Q BTU*100 ft d/r e R soil R pipe R sand R total Q BTU*100 ft , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,766 (-) Negative Q value indicates a heat gain Assumptions/Exclusions: 1. Assumed the chilled water is a constant 42 F. 2. Assumed moisture will migrate toward a chilled pipe, use a thermal conductivity value of 1.25 BTU/hr-ft- F for chilled water systems in the absence of any site-specific soil data as stated in 2004 ASHRAE Systems & Equipment Handbook, Chapter 11. Equations: 3. Assumed the annual soil temperature is 60 F. 4. Assumed soil moisture content is greater than 20 percent (worst case); sand is 1 ft on all sides of chilled water pipe. 5. Depth measured to top of pipe. Thermal Resistance of pipe material, h-ft- o F/Btu: Thermal Resistance of sand, h-ft- o F/Btu: Thermal Resistance of soil, h-ft- o F/Btu: Rate of Heat Transfer, Btu/h-ft:

23 JOB NO.: PAGE NO.: 1 COMPUTED BY: A. Welch-Castle DATE: 8/12/09 SUBJECT: HDPE SDR11 CHECKED BY: J.Cabrera DATE: 8/19/09 Heat loss Calculations with Gilsulate APPROVED BY: DATE: SHEET NO. 1 of Chilled Water Temperatures Depth (ranges) Soil Temperature Gilsulate Conductivity = k i Soil Thermal Conductivity=k soil Pipe Thermal Conductivity=k pipe 42 F 1 to 6 ft 60 F 0.05 BTU/hr-ft- F 1.25 BTU/hr-ft- F BTU/hr-ft- F Nominal Pipe Diameter Inside Diameter Outside Diameter Inside Radius Outside Radius Equivalent Diameter of Equivalent Radius of D i D o r i r o Gilsulate Gilsulate Envelope D e Envelope r e (in) (in) (in) (ft) (ft) (in) (ft) d/r e R soil R pipe R i R total Q BTU*100 ft d/r e R soil R pipe R i R total Q BTU*100 ft d/r e R soil R pipe R i R total Q BTU*100 ft d/r e R soil R pipe R i R total Q BTU*100 ft d/r e R soil R pipe R i R total Q BTU*100 ft d/r e R soil R pipe R i R total Q BTU*100 ft (-) Negative Q value indicates a heat gain Assumptions/Exclusions: 1. Assumed the chilled water is a constant 42 F. 2. Assumed moisture will migrate toward a chilled pipe, use a thermal conductivity value of 1.25 BTU/hr-ft- F for chilled water systems in the absence of any site-specific soil data as stated in 2004 ASHRAE Systems & Equipment Handbook, Chapter 11. Equations: 3. Assumed the annual soil temperature is 60 F. 4. Assumed soil moisture content is greater than 20 percent. 5. Assumed Gilsulate is 1 foot on all sides of the chilled water pipe. 6. Depth measured to top of pipe. Thermal Resistance of pipe material, h-ft- o F/Btu: Depth (ft) Thermal Resistance of insulation, h-ft- o F/Btu: Thermal Resistance of soil, h-ft- o F/Btu: Rate of Heat Transfer, Btu/h-ft:

24 High Density Polyethylene Pipe - HDPE SDR11 Thermal Conductivity = k p = 3.2 BTU-in/hr-ft^2-F defined in Piping Handbook Sixth Edition,Table D1.9, p. D.31 Pipe Size (in) Thickness (in) Outside Diameter (in) Inside Diameter (in)