1、December 2006 General Guidelines for Connecting HDPE Potable Water Pressure Pipes to DI and PVC Piping Systems TN - 36 -2006 i Foreword This technical note (TN) was developed and published with the technical help and financial support of the members of the Plastics Pipe Institute (PPI). The members
2、have shown their interest in quality products by assisting independent standard making and user organizations in the development of standards, and also by developing reports on an industry-wide basis to help engineers, code officials, specifying groups, and users. The TN has been prepared to provide
3、 those responsible for specifying, installing and connecting High Density Polyethylene (HDPE) solid wall piping systems to other Potable Water piping systems. These guidelines constitute a set of basic operations that has been demonstrated by test and experience to produce satisfactory connections w
4、ith commercially available materials. Each specific procedure must be acceptable to, and qualified by, the operator having legal responsibility for the performance of the piping system. The Plastics Pipe Institute, Inc., has prepared this technical note as a service to the industry. The information
5、in this note is offered in good faith and believed to be accurate at the time of its preparation, but is offered without any warranty, express or implied. Additional information may be needed in some areas, especially with regard to unusual or special applications. Consult the manufacturer or materi
6、al supplier for more detailed information. A list of member manufacturers is available from PPI. PPI does not endorse the proprietary products or processes of any manufacturer, and assumes no responsibility for compliance with applicable laws and regulations. PPI intends to revise this report from t
7、ime to time in response to comments and suggestions from users of this note. Please send suggestions for improvements to PPI. Information on other publications can be obtained by contacting PPI directly for visiting the web site. The Plastics Pipe Institute, Inc. (469) 499-1044 www.plasticpipe.org i
8、i Table of Content 1.0 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2.0 Connections to Ductile Iron Pipe / Fittings and PVC Pipe / Fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2.1 MJ Adapter Connections to DI Fittings . . . . . .
9、. . . . . . . . 1 2.2 Flanged Connections to DI Fittings . . . . . . . . . . . . . . . . . . . . 5 2.3 Solid Sleeve Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.4 HDPE Pipe Connection to PVC / DI Bell . . . . . . . . . . . . . . 10 2.5 HDPE Bell Adapters to PVC / DI Pipe E
10、nd . . . . . . . . . . . . 11 2.6 DI Valve with HDPE Pups . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.7 Dismantling Joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2.8 Transition Fitting HDPE to PVC . . . . . . . . . . . . . . . . . . . 14 2.9 Mechanical conne
11、ction HDPE to PVC . . . . . . . . . . . . . . . 15 3.0 Stiffener Installation Guidelines. . . . . . . . . . . . . . . . . . . . 17 4.0 Restraint Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4.1 Wall Anchors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12、 . . . . 19 4.2 Mechanical Restraint Anchor . . . . . . . . . . . . . . . . . . . . . . . 21 4.3 Buried Poly Anchor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4.4 Above Ground Pipeline Anchor . . . . . . . . . . . . . . . . . . . . . 22 4.5 HDPE to PVC Slip-Joint Anchor Fitting
13、 . . . . . . . . . . . . . . 23 5.0 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24 1 General Guidelines for Connecting HDPE Potable Water Pressure Pipes to DI and PVC Piping Systems 1.0 Introduction High Density Polyethylene (HDPE) pipe is normally connected
14、by heat fusion which creates a leak-free bond as strong, if not stronger, than the pipe itself in tensile and pressure applications. These heat fused joints are also self restrained and require no external restraining method to prevent the joint from pulling apart. In this document, we will cover th
15、e various ways to connect HDPE pipe to existing Ductile Iron (DI) and PVC piping systems. In most cases, HDPE pipe can be easily connected to standard Ductile Iron fittings. Because Ductile Iron and PVC pipe are normally joined with bell and spigot joints, the connection to these systems generally r
16、equires some sort of restraint to prevent the expansion/contraction of HDPE pipe from pulling the existing systems joints apart. Several different restraining methods will be discussed. Before using any mechanical fitting, contact the manufacturer to verify the fitting is designed for HDPE pipe. 2.0
17、 Connections to Ductile Iron Pipe / Fittings and PVC Pipe / Fittings 2.1 MJ Adapter Connections to DI Fittings MJ (mechanical joint) Adapters are manufactured in standard IPS and DIPS sizes for connecting IPS sized or DIPS sized polyethylene pipe to mechanical joint fittings and appurtenances that m
18、eet AWWA C111/ANSI A21.11. When connected, they seal against leakage and restrain against pullout. No additional external clamps or tie rod devices are required unless connected to an existing piping system. In that case, refer to Section 4 on restraint recommendations. In water systems that use duc
19、tile iron pipe (DIP), many valves are connected to pipe using MJ Adapters. A typical MJ Adapter Kit is shown below in Figure 1. Refer to the fitting manufacturers installation instructions for joining a MJ Adapter to a DI Fitting. In general, the procedure is to first attach the HDPE MJ Adapter to t
20、he HDPE pipe line. Slip the Gland Ring over the pipe end and then butt fuse the HDPE MJ Adapter to the end of the pipe using the PPI Generic Butt Fusion Joining 2 Procedure TR-33. Install the Gasket over the MJ Adapter and align the fitting with the socket hub of the ductile iron fitting. Lubricate
21、the gasket, the end of the MJ adapter, and the inside of the socket hub with an approved pipe lubricant meeting AWWA C111. Do not use soapy water. Insert the MJ Adapter into the socket hub. Make sure it is evenly and completely seated in the socket hub. The MJ Adapter and the socket hub must be alig
22、ned straight into each other. Insert the gland bolts, and run the nuts up finger-tight. Tighten the gland bolts evenly to the fitting manufacturers recommended procedures. This connection is used with a large number of DI fittings, some of which are shown in Figure 4. When connecting to a valve with
23、 an MJ connection, longer T-Bolts may be required. If the T-Bolts that come with the kit are not long enough for the assembly, use a coupling nut and Grade 5 all thread to make up the length required (Figure 5). Figure 1 HDPE MJ Adapter Kit 3 Figure 2 MJ connection to typical gate valve with MJ ends
24、 Figure 3 MJ Connection to DI fitting 4 Figure 4 Ductile Iron Fittings MJ Connection 5 Figure 5 T-Bolt Extension 2.2 Flanged Connection to DI Fittings It is common to use a flanged connection to join HDPE pipe to HDPE pipe in a close quarter tie-in or when a piping section will require removal in th
25、e future. Flanged joints are also used to attach HDPE pipe to valves or DI fittings. The parts for a flange connection are the HDPE Flange Adapter, Back-Up Ring, Gaskets and Bolts, Nuts and Washers. This connection is made by first sliding the Back-Up Ring over the pipe end and then butt fusing the
26、HDPE Flange Adapter to the end of the pipe using the PPI Generic Butt Fusion Joining Procedure TR-33. Then align the flanges and back-up rings and follow the fitting manufacturers recommended procedures for bolting the flanges together. The service pressure rating for the back-up ring should meet or
27、 exceed the service pressure in the pipe. Gaskets may not be required, depending on the pressure in the pipeline. Gaskets are usually used for higher pressure application (over 100 psi) and must be used for connections between polyethylene and non-polyethylene flanges. If gaskets are used, the gaske
28、t manufacturer should recommend the gasket to use with polyethylene pipe. This is considered a “fully restrained joint” and should not need external restraint devices. 6 Figure 6 Flange Adapter Assembly Figure 7 Fused Manifold Assembly with Flange Adapters And Back Up Rings 7 Figure 8 Flange Adapter
29、 Bolted Assembly Cross Section Figure 9 Ductile Iron Tee with Flanged Outlet 8 2.3 Solid DI Sleeve Connections to HDPE pipe Solid Sleeves are ductile iron fittings designed to connect DI / PVC pipe to other piping materials including HDPE pipe. They come in a variety of configurations depending on t
30、he application. Most solid sleeves have a flange or MJ hub to attach to the HDPE pipe. On the ductile iron pipe side, a Megalug flange is attached to the pipe and a gasket is installed over the pipe and into the sleeve before bolting the Megalug to the Sleeve flange. A standard HDPE MJ Adapter kit i
31、s used on the HDPE pipe side to complete the assembly. Be sure to use the manufacturers recommended bolting procedures for this assembly. (see Figure 10) Figure 10 Solid DI Sleeve Connections to HDPE pipe 9 Another solid sleeve design is called a “One Bolt” Solid Sleeve and can be used to connect HD
32、PE pipe to PVC or DI pipe. This is similar to a standard HDPE mechanical connector but has a special locking ring that grips the HDPE pipe to prevent pullout. It is recommended to use a stiffener inside the HDPE pipe, especially if the DR is more than 11. This connection can be installed very quickl
33、y in the field and may also be used for repair. Consult with the sleeve manufacturer for application and restraint advice. Figure 11 One Bolt Solid Sleeve Connection 10 2.4 HDPE Pipe Connection to DI or PVC Bell End Another method of restraining the above mentioned connection would be the use of a r
34、estraint harness and the attachment of flex restraint sections to the HDPE pipe. These flex restraint pieces are electro-fused to the HDPE pipe to achieve the proper stab depth in the PVC or DI bell and the restraint harness plate is attached behind them. The opposite end of the restraint harness is
35、 attached behind the DI /PVC hub. Install the HDPE pipe in the PVC/DI bell until it bottoms out on the flex restraints and tighten the tie rods to prevent the assembly from pulling apart. As discussed above: to maintain proper contact with the seal in the DI /PVC fitting, it is recommended that a st
36、iffener be installed in the HDPE pipe end. Figure 12 HDPE pipe connection to DI / PVC bell end using Flex Restraints on the HDPE pipe 11 2.5 HDPE Bell Adapters to DI or PVC Pipe End There are HDPE Bell Adapters available, up to 24” IPS, that are machined to the standard MJ Adapter internal configura
37、tions and have an external stainless steel backup ring installed to ensure positive seal contact. This connection incorporates a back-up flange behind the HDPE Adapter and a Mega-Lug flange on the PVC or DI pipe. Standard MJ seals and bolts are used to connect the assembly. Figure 13 HDPE Bell Adapt
38、er to DI or PVC Pipe End 12 2.6 DI Valve with HDPE Ends In most potable water systems, a valve is installed between the main and the hydrant. This can be fused in line using this special valve assembly with HDPE pipe installed on each side and available up to 12” pipe size. It has an HDPE ends insta
39、lled on each side of the valve. Figure 14 Ductile Iron Gate Valve with HDPE Ends 13 2.7 Dismantling Joint Dismantling joints simplify installations and replacement of flanged fittings in retrofitting applications. Dismantling Joints provide the solution for adding, repairing or replacing flanged fit
40、tings within a flanged pipe system. In all applications, a restrained dismantling joint is required unless otherwise specified. (see Section 4). Adjustable, slip joint design accommodates either wide gaps or close quarter installations and eliminates the need for precise measurements between flange
41、connections. Available in sizes 2” and larger, for ductile iron or flanged HDPE piping systems. Standard flanges AWWA C207 Class D Flange. Other flanges are available upon request. Figure 15 Dismantling Joint 14 2.8 Transition Fitting HDPE pipe to DI / PVC pipe A transition fitting is a mechanical a
42、ssembly of HDPE and PVC or DI pipe. The resulting product will allow a butt fusion joint on the HDPE end and standard PVC or DI mechanical connection on the other end. (See Figures 17, 18 the OD rings prevent the pipeline from moving in expansion or contraction in either direction. The width of the
43、center groove can be made as wide as required so as to get sufficient grip on the HDPE pipe for the thermal excursions expected. 23 4.5 HDPE to PVC Slip-Joint Anchor Fitting Figure 29 HDPE to PVC Slip-Joint Anchor Configurations A gasketed PVC pipe bell to plain end HDPE pipe should be restrained ag
44、ainst HDPE thermal contraction and pressure thrust, to avoid possible long-term joint separation. The PVC-Bell slip-Joint Anchor Fitting (PVC-SJA Fitting) with internal stiffener to support gasket load, provides the restrained connection from HDPE pipe to bell-end PVC pipe. (For plain-end PVC, refer
45、 to Section 2.5: the HDPE Bell-Adapter Fitting). When the restraint rings with tie-rod option is specified, the rods and rings are supplied separately from the SJA fitting. 24 5.0 References: Plastics Pipe Institute - www.plasticpipe.org PPI Polyethylene Pipe Handbook Technical Report TR-33 “Generic
46、 Butt Fusion Procedure” Technical Report TR-41 “Generic Saddle Fusion Procedure” Technical Note TN-34 “Installation Guidelines for Electrofusion Couplings 14“ and Larger (2004)” Technical Note TN-35 “General Guidelines Repairing Buried HDPE potable Water Pressure Pipes” AWWA - PE Pipe- Design and in
47、stallation, M55, www.awwa.org ASTM - F1025 “Selection and Use of Full-Encirclement-Type Band Clamps for Reinforcement or Repair of Punctures or Holes in Polyethylene Gas Pressure Pipe” Fusion Equipment Manufacturers Connectra Fusion Fast Fusion McElroy Manufacturing, Inc. Ritmo America Electro-F
48、usion Fitting and Equipment Manufacturers Central Plastics Co. Friatec Kerotest-Innogaz Polyethylene Fitting Manufacturers Central Plastics Independent Pipe Products, Inc. ISCO Industries www.isco- Industrial Pipe Fittings KWH Pipe www.kwhpipe.ca Poly-Cam Pipe Manufacturers ARNCO Charter Plastics Endot Industries Independent Pipe Products, Inc. J-M Manufacturing KWH Pipe www.kwhpipe.ca Lamson and Sessions Performance Pipe PolyPipe, Inc. Silverline
