PRE-PRINT. IaPMo Is InstallatIon standard For CoPPEr PlUMBInG tube, PIPE, and FIttInGs

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1 InstallatIon standard For CoPPEr PlUMBInG tube, PIPE, and FIttInGs IaPMo Is scope 1.1 Installation and material of copper tube, pipe and fittings in drainage, vent, and water systems shall comply with this standard and the current edition of the Uniform Plumbing Code [UPC] TM, published by the International Association of Plumbing and Mechanical Officials (IAPMO). Note: The following sections of the Uniform Plumbing Code shall apply Testing of systems Minimum standards Workmanship Prohibited fittings and practices Protection of piping materials and structures Hangers and supports Types of joints Special joints Prohibited joints and connections Increasers and reducers Closet flanges Materials Water piping Water piping Marking of tubing Flexible water connectors Restriction of used piping Flared joints Use of joints, copper water tube Relief valve drain Installation, inspection, testing Size of potable piping Drainage and vent piping Ground joint, flared or ferrule connections Cleanouts Materials, drainage piping Chemical or industrial waste piping Materials, vent piping Use of copper tubing Materials, rain water piping Materials, roof drains Table 14-1 Standards ASME B Cast Copper Alloy Solder-Joint Pressure Fittings ASME B Wrought Copper and Copper Alloy Solder-Joint Pressure Fittings ASME B Cast Bronze Solder-Joint Drainage Fittings - DWV ASME B Wrought Copper and Copper Alloy Solder-Joint Drainage Fittings ASME B Wrought Copper and Copper Alloy Braze-Joint Pressure Fittings ASTM B 32 Solder Metal ASTM B 42 Seamless Copper Pipe, Standard Sizes ASTM B 75 Seamless Copper Tubes ASTM B 88 Seamless Copper Water Tube ASTM B 302 Threadless Copper Pipe, Standard Sizes ASTM B 306 Copper Drainage Tube (DWV) ASTM B 813 Liquid and Paste Fluxes for Soldering Applications of Copper and Copper Alloy Tube ASTM B 828 Standard Practice for Making Capillary Joints by Soldering of Copper and Copper Alloy Tube and Fittings Appendix A Chart A-4 Friction loss per 100 ft. (30.5 m) 2.0 ProdUCt requirements 2.1 Minimum standards Materials. Materials shall comply with the appropriate standard in Table 14-1 of the UPC. [UPC 301.1] Note: The nominal or standard size of copper plumbing tube is always inch (3.175 mm) or one-eighth (1/8) inch (3.175 mm) smaller than the actual outside diameter dimension of the tube. For example, 3 inch (76 mm) nominal size copper plumbing tube measures 3-1/8 inch (79 mm) O.D., 1/2 inch (12.7 mm) nominal size copper plumbing tube measures 5/8 inch (15.9 mm) O.D., etc. UnIForM PlUMBInG CodE 345

2 2.1.2 Markings. Markings shall be visible for inspection. Products that are covered by this standard shall be identified in accordance with the standard found in Table [UPC 301.1] tube and threadless Pipe. Water tube (Types K, L, M), drainage tube (Type DWV), and threadless pipe (TP), shall bear the following incised marking at not over 18 inch (457 mm) intervals: (a) Manufacturer s name or trademark; and (b) Tube type Pipe (Copper and Copper alloy) Pipe shall bear the following incised marking at not over 18 inch (457 mm) intervals: (a) Manufacturer s name or trademark; and (b) Pipe type Fittings Fittings shall bear the following markings: (a) Manufacturer s name or trademark; and (b) "DWV" on drainage fittings. 2.2 type of Joints General Information Copper tube and fittings may be joined in a number of ways, depending on the purpose of the system. Soldering and brazing with capillary fittings are the methods used most. The American Welding Society (AWS) defines soldering as a joining process which takes place below 840 F (449 C) and brazing as a similar process which occurs above 840 F (449 C) but below the melting point of the base metals. In actual practice for copper systems, most soldering is done at temperatures from about 350 F (177 C) to 550 F (288 C), while most brazing is done at temperatures ranging from 1100 F (593 C) to 1500 F (816 C). The choice between soldering or brazing will generally depend on operating conditions. Solder joints are generally used where the service temperature does not exceed 250 F (121 C), while brazed joints are used where greater tensile strength is required to resist vibration, or pressure or temperature cycling, or where system temperatures are as high as 350 F (177 C). Although brazed joints offer higher joint strength in general, the annealing of the tube and fitting which results from the higher heat used in the brazing process can cause the rated pressure of the system to be less than that of a soldered joint. This fact should also be considered in choosing which joining process to use. Mechanical joints are used frequently for some underground connections, for joints where the use of heat is impractical and for joints that may have to be disconnected from time to time. [UPC 316.1] Fittings for soldered, Brazed, and Mechanical Joints Cast fittings are available in all standard tube sizes and in a wide variety of types to cover needs for plumbing. They can be either soldered or brazed, although brazing cast fittings requires care. Wrought copper pressure fittings are also available over a wide range of sizes and types. These, too, can be joined by either soldering or brazing and wrought fittings are preferred where brazing is the joining method. Otherwise, the choice between cast and wrought fittings is largely a matter of the user s preference and availability. According to the American Welding Society, the strength of a brazed joint will meet or exceed that of the tube and fitting being joined when the joint overlap and the depth of the filler metal penetration is a minimum of three times the thickness of the thinner base metals (tube or fitting) and a well-developed fillet (cap) is present. The strength of a brazed copper tube joint does not vary much with different filler metals but depends on maintaining the proper clearance between the outside of the tube and the socket (cup) of the fitting. Copper tube and solder-type pressure fittings are accurately made for each other, and the tolerances permitted for each assure the capillary space will be within the limits necessary for a joint of satisfactory strength. However, the depths of the socket are considerable deeper than the three times required by AWS. There are standards available for the manufacture of fittings made specifically for brazing, these include ASME B and MSS SP 73. When fittings are made to these standards, they cannot be soldered. They must be brazed Mechanical Joints Flared-tube fittings provide metal-to-metal contact similar to ground joint unions; both can be easily taken apart and reassembled. Grooved end mechanical fittings are also available in sizes 2-inches to 6-inches. Mechanical joint fittings are especially useful where residual water cannot be removed from the tube and soldering is difficult. Mechanical joints may be required where a fire hazard exists and the use of a torch to make soldered or brazed joints is not allowed. Also, soldering under wet conditions can be very difficult and mechanical joints may be preferred under such circumstances. [UPC 316.0] solders Most solders referenced in ASTM B 32 can be used to join copper tube and fittings in potable water systems. 346 UnIForM PlUMBInG CodE

3 Note: Users of the Uniform Plumbing Code are reminded that provisions of the Federal Safe Drinking Water Act of 1986 (SDWA), which all must obey, forbid the use of solder which contains in excess of 0.2% of lead, in potable water systems. The provisions of the act are incorporated in all ordinances, statutes, state and municipal regulations by reference and by operation of law. [UPC 316.0] The selection of a solder depends on the operating pressure and temperature of the system. Consideration should also be given to the stresses on the joint caused by thermal expansion and contraction. However, stresses due to temperature changes should not be significant in two commonly encountered cases: when tube lengths are short, or when expansion loops are used in long tube runs. Solder is generally used in wire form, but pastetype solders are also available. These are finely granulated solders in suspension in a paste flux. These solder/flux pastes must meet the requirements of ASTM B 813. When using paste-type solders, observe these four rules: 1. Wire solder must be applied in addition to the paste to fill the voids and assist in displacing the flux, otherwise the surfaces may be well "tinned" and yet there may not be a good joint with a continuous bond. Use the same type of solder (e.g., or 95-5) as that used in the paste. 2. The paste mixture must be thoroughly stirred if it has been standing in the can for more than a very short time, as the solder has a tendency to settle rapidly to the bottom. 3. The flux cannot be depended on to clean the tube. Cleaning should be done manually as is recommended for any other flux and solder. 4. Remove any excess flux. Solders are available that contain small amounts of silver or other additives to impart special properties. Such solders may require special fluxes. The manufacturer s recommendations should be consulted regarding proper procedures and fluxes for such solders and about the expected properties soldering Flux The functions of the soldering flux are to remove residual traces of oxides, to promote wetting and to protect the surfaces to be soldered from oxidation during heating. The flux should be applied to clean surfaces and only enough should be used to lightly coat the areas to be joined. An oxide film may reform quickly on copper after it has been cleaned. Therefore, the flux should be applied as soon as possible after cleaning. CaUtIon Careless workmanship, especially during flux applications, can result in corrosion of the tube long after the system has been installed. If excessive flux is used, the residue inside the tube can cause corrosion. In an extreme case, such residual flux can actually lead to perforation through the tube wall causing leakage. To guard against this danger, it is important (1) to choose a flux that is manufactured to ASTM B 813, and (2) to use only the minimum amount actually needed to make the joint. 2.3 solder Joints Soldering and brazing both involve basic steps, based on ASTM Standard Practice B 828, which must be executed with care and craftsmanship. The steps are: (1) Measuring (2) Cutting (3) Reaming (4) Cleaning (5) Fluxing (6) Assembly and support (7) Heating (8) Applying the filler metal (9) Cooling and cleaning Each step contributes to a strong, dependable joint Measuring Measuring the length of each tube segment must be accurate. Inaccuracy can compromise joint quality. If the tube is too short it will not reach all the way into the socket of the fitting and a proper joint cannot be made. If the tube segment is too long there is a danger of cocking the tube in the fitting and putting strain on the system which could affect service life Cutting Once the tube is measured, it can be cut. Cutting can be accomplished in a number of different ways to produce a satisfactory square end. The tube can be cut with a disc-type tube cutter, a hacksaw, an abrasive wheel, or with a stationary or portable bandsaw. Care must be taken that the tube is not deformed while being cut. Regardless of the method, the cut must be square with the run of the tube so that the tube will seat properly in the fitting socket. UnIForM PlUMBInG CodE 347

4 2.3.4 reaming All pipe and tube shall be reamed to the full I.D. of the pipe and tube to remove the small burr created by the cutting operation. If this rough, inside edge is not removed erosion-corrosion may occur due to localized turbulence and high velocity. Tools used to ream tube ends include the reaming blade on the tube cutter, half-round or round files, a pocket knife, or a suitable deburring tool. With annealed tube, care must be taken not to deform the tube end by applying too much pressure. Both the inside and the outside of the tube may require removal of the burr, especially in large diameters Cleaning The removal of all oxides and surfaces soil is crucial if filler metal is to flow properly into the joint. Failure to remove them can interfere with capillary action and may lessen the strength of the joint and cause failure. Mechanical cleaning is a simple operation. The end of the tube should be lightly abraded using sand cloth or nylon abrasive pads for a distance only slightly more than the depth of the fitting socket. The socket of the fitting should also be cleaned using sand cloth, abrasive pads, or a properly sized fitting brush. Copper is a relatively soft metal. If too much material is removed, a loose fit will result and interfere with satisfactory capillary action in making the joint. The capillary space between tube and fitting is approximately inch (0.10 mm). Solder or brazing filler metal can fill this gap by capillary action. This spacing is critical for the filler metal to flow into the gap and form a strong joint. Surfaces once cleaned should not be touched with bare hands or oily gloves. Skin oils, lubricating oils, and grease impair filler metal flow and wetting Fluxing Stir the flux before use. Flux will dissolve and remove traces of oxide from the cleaned surfaces to be joined, protect the cleaned surfaces from reoxidation during heating, and promote wetting of the surfaces by the solder. A thin, even coating of flux should be applied with a brush to both tube and fitting as soon as possible after cleaning. Do not apply with fingers. Chemicals in the flux can be harmful if carried to the eyes, mouth, or open cuts assembly and support After both tube and fitting surfaces are properly fluxed, they should be assembled, making sure the tube seats against the base of the fitting socket. A slight twisting motion ensures even distribution by the flux. Remove any excess flux. Care must be taken to assure that the tube and fittings are properly supported to ensure a uniform capillary space around the entire circumference of the joint. Uniformity of capillary space will ensure good filler metal penetration if the guidelines of successful joint making are followed. Excessive joint clearance can cause the filler metal to crack under stress or vibration. The joint is now ready for soldering. Joints prepared and ready for soldering should be completed the same day and not left unfinished overnight Heating WARNING: When dealing with an open flame, high temperatures, and flammable gases, safety precautions must be observed as described in the ANSI /ASC Z49.1 Standard. Heat is generally applied using an air/fuel torch. Such torches use acetylene or an LP gas. Electric resistance tools can also be used. Begin heating with the flame perpendicular to the tube on the bottom. The copper tube conducts the initial heat into the fitting socket for even distribution of heat in the joint area. The extent of this preheating depends upon the size of the joint. Experience will indicate the amount of time needed. Preheating of the assembly should include the entire circumference of the tube in order to bring the entire assembly up to a suitable preheat condition. However, for joints in the horizontal position, avoid directly preheating the top of the joint to avoid burning the soldering flux. The natural tendency of heat to rise will ensure adequate preheat of the top of the assembly. Next, move the flame onto the fitting socket. Sweep the flame alternately from the fitting socket back onto the tube a distance equal to the depth of the fitting socket. Touch the solder to the joint. If the solder does not melt, remove it and continue the heating process. Be careful not to overheat or to direct the flame into the fitting cup. This could cause the flux to burn and destroy its effectiveness. When the solder begins to melt, the heat should be directed to the base of the cup to aid capillary action in drawing the molten solder into the fitting socket towards the heat source applying the Filler Metal For joints in the horizontal position, start applying the solder slightly off-center at the bottom of the joint. When the solder metal begins to melt from the heat of the tube and fitting do not use 348 UnIForM PlUMBInG CodE

5 the torch to melt the solder; push the solder straight into the joint while keeping the torch at the base of the fitting socket and slightly ahead of the point of application of the solder. Continue this technique across the bottom of the fitting and up the side to the top of the fitting. Return to the beginning, overlapping slightly by re-melting the solder at the point and proceed up the other side to the top, again overlapping slightly. For joints in the vertical position, a similar sequence of overlapping passes should be made, starting wherever is convenient. Molten solder will be drawn into the joint by capillary action regardless of whether the solder is being fed upward, downward or horizontally. IMPOR- TANT: Always remember to let the heat lead the alloy. Do not apply the filler metal in front of the heat Cooling and Cleaning After the joint has been completed, natural cooling is best. Shock cooling with water may cause unnecessary stress on the joint and result in eventual failure. When cool, clean off any remaining flux with a wet rag testing Test all completed assemblies for joint integrity following the procedures described in the body of this code. Completed systems should be flushed to remove excess flux and debris as soon as possible after completion. 2.4 Brazed Joints Brazing is another commonly used method for joining copper tube. Making brazed joints is similar to making soldered joints with respect to measuring, cutting, reaming, cleaning, assembly, and support. And as in soldering, the brazing filler metal is melted by the heat of the tube and fitting and drawn into the joint by capillary action. The major differences between soldering and brazing are the: Type of flux used; Composition of filler metal; and Amount of heat required to melt the filler metal Brazing Flux The fluxes used for brazing copper joints are different in composition from soldering fluxes. The two types cannot be used interchangeably. Unlike soldering fluxes, brazing fluxes are water based. Similar to soldering fluxes, brazing fluxes dissolve and remove residual oxide from the metal surfaces, protect the metal from reoxidation during heating and promote wetting of the surfaces to be joined by the brazing filler metal. Fluxes also provide the craftsman with an indication of temperature. Application of the flux is the same as when soldering. If the outside of the fitting and the heat-affected area of the tube are covered with flux (in addition to the end of the tube and the cup), oxidation will be prevented and the appearance of the joint will be greatly improved Brazing Filler Metals Brazing filler metals suitable for joining copper tube systems are of two classes. Classified according to their components, they are: BCuP (Brazing-Copper-Phosphorus) and BAg (Brazing-Silver). BCuP filler metals are preferred for joining copper tube and fittings if codes and construction specifications allow it. The phosphorus in them acts as a fluxing agent and the lower percentage of silver makes them relatively low cost. When using copper tube, wrought copper fittings, and BCuP brazing filler metal, fluxing is optional. However, when cast fittings are brazed, flux must be used Heating WARNING: When dealing with an open flame, high temperatures, and flammable gases, safety precautions must be observed as described in the ANSI/ASC Z49.1 Standard. Oxy/fuel torches are generally used for brazing because of their higher temperatures. However, recent innovations in tip design make air/fuel torches useful for brazing on a wide range of sizes for brazing. The heating operation is the same as for soldering. Heat the tube first, beginning about one inch from the edge of the fitting, sweeping the flame around the tube in short strokes at right angles to the axis of the tube. It is very important that the flame be in motion and not remain on any one point long enough to damage the tube. Switch the flame to the fitting at the base of the fitting socket. Heat uniformly, sweeping the flame from the fitting to the tube. Avoid excessive heating of cast fittings or they may crack applying Brazing Filler Metal Apply the brazing filler metal at the point where the tube enters the socket of the fitting. When the proper temperature is reached, the filler metal will flow readily into the space between the tube and fitting socket, drawn in by the natural force of capillary action. UnIForM PlUMBInG CodE 349

6 Keep the flame away from the filler metal itself as it is fed into the joint. The temperature of the tube and fitting at the joint should be high enough to melt the filler metal. Keep both the tube and fitting heated by moving the flame back and forth from one to the other as the filler metal is drawn into the joint. When the joint is properly made the filler metal will be drawn into the fitting socket by capillary action, and a continuous fillet (cap) of filler metal will be visible completely around the joint. To aid in the development of this fillet during brazing, the flame should be kept slightly ahead of the pint of filler metal application. When brazing horizontal joints, it is preferable to first apply the filler metal slightly off-center of the bottom of the joint, proceeding across the bottom of the joint and continuing up the side to the top of the joint. The return to the beginning point, overlapping slightly. This procedure is identical to that used for soldering. Also, similar to the soldering process, make sure the operations overlap. On vertical joints, it is immaterial where the joint is made. If the opening of the fitting socket is pointing down, care should be taken to avoid overheating the tube, as this may cause the brazing filler metal to run down the outside of the tube. If the filler metal fails to flow, or has the tendency to ball-up, it indicates either that there is oxide on the surfaces being joined or that the parts to be joined are not hot enough. If the filler metal refuses to enter the joint, the fitting cup is not hot enough. Most poorly made braze joints result from either the tube or the fitting not being hot enough. If filler metal tends to flow over the outside of either part of the joint, it indicates that part is overheated in comparison to the other. When the joint is completed, a continuous fillet should be visible completely around the joint. Larger diameter tube is more difficult to heat to the desired temperature. The use of a heating tip or rosebud may be necessary to maintain the proper temperature over the area being brazed. Once total heat control is attained, follow the same procedures used for smaller tube Cooling and Cleaning When the brazed joint is finished, allow it to cool naturally. Flux residues and some oxides formed by heating can be removed by washing with hot water and brushing with a stainless steel wire brush testing Test all completed assembles for joint integrity following the procedures described in the body of this code. Completed systems should be flushed to remove excess flux and debris as soon as possible after completion Purging Some installations, such as medical gas, highpurity gas, and ACR systems, require the use of an inert gas during the brazing process. The purge gas displaces oxygen from the interior of the system while it is being subjected to the high temperatures of brazing and therefore eliminates the possibility of oxide formation on the interior of the tube surface. 2.5 Flared Joints Flared Joints with Impact Flaring tools Step 1 Cut the tube to the required length. Step 2 Remove all burrs. This is very important to assure metal-to-metal contact. Step 3 Soft temper tube, if deformed, should be brought back to roundness with a sizing tool. This tool consists of a plug and sizing ring. Step 4 Slip the coupling nut over the end of the tube. Step 5 Insert flaring tool into the tube end. Step 6 Drive the flaring tool by hammer strokes, expanding the end of the tube to the desired flare. This requires a few moderately light strokes. Step 7 Assemble the joint by placing the fitting squarely against the flare. Engage the coupling nut with the fitting threads. Tighten with two wrenches, one on the nut and one on the fitting Flared Joints with screw-type Flaring tools Steps 1-4 Same as for impact flaring previously described. Step 5 Clamp the tube in the flaring block so that the end of the tube is slightly above the face of the block. Step 6 Place the yoke of the flaring tool on the block so that the beveled end of the compressor cone is over the tube end. Step 7 Turn the compressor screw down firmly, forming the flare between the chamber in the flaring block and the beveled compressor cone. Step 8 Remove the flaring tool. The joint can now be assembled as in Step 6 for impact flaring. 2.6 sizing, Velocity To avoid excess system noise and the possibility of erosion-corrosion, flow through copper tube 350 UnIForM PlUMBInG CodE

7 systems should not exceed velocities of 8 feet per second for cold water and 5 feet per second in hot water up to approximately 140 F (60 C) [UPC 610.0] In systems where water temperatures routinely exceed 140 F (60 C), lower velocities such as 2 to 3 feet per second should not be exceeded. In addition, where 1/2-inch and smaller tube sizes are used, to guard against localized high velocity turbulence due to possible faulty workmanship (e.g. burrs at tube ends which were not properly removed) or unusually numerous, abrupt changes in flow direction, lower velocities should be considered. Due to constant circulation and elevated water temperatures, particular attention should be paid to velocities in circulation hot water systems. Both the supply and return piping should be sized such that the maximum velocity does not exceed the above recommendations. Care should be taken to ensure that the circulating pump is not oversized and the return piping is not undersized, both common occurrences in installed copper piping systems. 3.0 GEnEral InForMatIon 3.1 It is not possible to cover all the variables of a plumbing system; however, the following information may prove helpful: Expansion loops Copper tube, like all piping materials, expands and contracts with temperature changes. Therefore, in a copper tube system subjected to excessive temperature changes, the line tends to buckle or bend when it expands unless compensation is built into the system. Severe stresses on the joints may also occur. Such stresses, buckles, or bends are prevented by the use of expansion joints or by installing offsets, U bends, coil loops, or similar arrangements in the tube assembly. These specially shaped tube segments take up expansion and contraction without excessive stress. The expansion of a length of copper tube may be calculated from the formula: Calculations for expansion and contraction should be based on the average coefficient of expansion of copper, which is per F (1.692 x 10-5 per C), between 70 F (21 C) and 212 F (100 C). For example, the expansion of each 100 feet (3048 mm) of length of any size tube heated from room temperature (70 F) (21 C) to 170 F (77 C) (a 100 F (38 C) rise) is inches (28.7 mm). 100 x 100 ft x 12 in./ft x in./in./ F = in., or 55.6 x m x 1000 mm/m x x 10-5 mm/mm/ C = 28.7 mm 3.2 tube supports - See Table 3-2 and Section in the Uniform Plumbing Code. 3.3 Bending Copper tube, properly bent, will not collapse on the outside of the bend and will not buckle on the inside of the bend. Tests demonstrate that the bursting strength of a bent copper tube can be greater than it was before bending. Because copper is readily formed, expansion loops and other bends necessary in an assembly are quickly and simply made if the proper method and equipment are used. Simple hand tools employing mandrels, dies, forms, and fillers, or power-operated bending machines are used. Both annealed tube and bending-temper tube can be bent with hand benders. The proper size bender for each size tube must be used. Usually the size of the tool corresponds to the nominal outside diameter of the tube, not the standard tube size. For a guide to the typical bend radii, see the following bending guide for copper tube. adopted: 1969 revised: 1973, 1975, 1987, 1989, 1993, 2000, 2003, 2006 Temperature Rise ( F) x Length (feet) x 12 (inches per foot) x Expansion Coefficient (in. per in. per F) = Expansion (inches), or Temperature Rise ( C) x Length (meter) x 1000 (mm per meter) x Expansion Coefficient (mm per mm per C) = Expansion (mm). UnIForM PlUMBInG CodE 351

8 BEndInG GUIdE For CoPPEr tube Minimum tube size, tube type temper Bend radius, type of Bending Inches (mm) Inches (mm) Equipment 1/4 (6.4) K, L Annealed 3/4 (19.1) Lever type 3/8 (9.5) K, L Annealed 1-1/2 (38) Lever or gear type 3 (76) None; by hand* K, L, M Drawn 1-3/4 (44) Gear type 1/2 (12.7) K, L Annealed 2-1/4 (57) Lever or gear type 4-1/2 (114) None; by hand* K, L, M Drawn 2-1/2 (64) Gear type 3/4 (19.1) K, L Annealed 3 (76) Lever or gear type K 4-1/2 (114) None; by hand* L 6 (152) None, by hand* K Drawn 3 (76) Gear type K, L 4 (102) Heavy-duty gear type 1 (25.4) K, L Annealed 4 (102) Gear type 7-1/2 (191) None; by hand* 1-1/4 (32) K, L Annealed 9 (229) None; by hand* * When bending by hand, without the use of bending equipment, a circular wooden disc is used. The radius of the disc should be about 1/4 to 1/2 inch less than the minimum bend radius shown. 352 UnIForM PlUMBInG CodE