Use the photos on these pages to identify the plumbing fittings specified in the project how-to directions found in this book. Each fitting shown is available in a variety of sizes to match your needs. Always use fittings made from the same material as your pipes.
Pipe fittings come in a variety of shapes to serve different functions within the plumbing system. DWV fittings include:
Vents: In general, the fittings used to connect vent pipes have very sharp bends with no sweep. Vent fittings include the vent T and vent 90º elbow. Standard drain pipe fittings can also be used to join vent pipes.
Horizontal-to-vertical drains: To change directions in a drain pipe from the horizontal to the vertical, use fittings with a noticeable sweep. Standard fittings for this use include waste T-fittings and 90º elbows. Y-fittings and 45º and 22 1⁄2º elbows can also be used for this purpose.
Vertical-to-horizontal drains: To change directions from the vertical to the horizontal, use fittings with a very pronounced, gradual sweep. Common fittings for this purpose include the long-radius T-Y-fitting and some Y-fittings with 45º elbows.
Horizontal offsets in drains: Y-fittings, 45º elbows, 221⁄2º elbows, and long sweep 90º elbows are used when changing directions in horizontal pipe runs. Whenever possible, horizontal drain pipes should use gradual, sweeping bends rather than sharp turns.
Basic DWV tree shows the correct orientation of drain and vent fittings in a plumbing system. Bends in the vent pipes can be very sharp, but drain pipes should use fittings with a noticeable sweep. Fittings used to direct falling waste water from a vertical to a horizontal pipe should have bends that are even more sweeping. Your local plumbing code may require that you install cleanout fittings where vertical drain pipes meet horizontal runs.Water supply fittings are available for copper (top), CPVC plastic (center), and PEX (bottom). Fittings for CPVC and copper are available in many shapes, including: unions (A), reducers (B), 90º elbows (C), reducing elbows (D), 45º elbows (E), T-fittings (F), reducing T-fittings (G), drop-ear elbows (H), threaded adapters (I), and caps (J). Common PEX fittings (bottom) include unions (K), PEX-to-copper unions (L), 90º elbows (M), T-fittings (N), plugs (O), drop-ear elbows (P), and threaded adapters (Q).Water supply valves are available in brass or plastic and in a variety of styles, including: drain-and-waste valves (A), gate valve (B), full-bore ball valves (C), fixture shutoff valve (D), vacuum breaker (E), and hose bib (F).Support materials for pipes include: plastic pipe hangers (A), copper J-hooks (B), copper wire hangers (C), riser clamp (D), plastic pipe straps (E), copper pipe straps (F), flexible copper, steel, and plastic pipe strapping (G, H, I). Do not mix metal types when supporting metal pipes; use copper support materials for copper pipe, and steel for steel and cast-iron pipes.Support materials for pipes include: plastic pipe hangers (A), copper J-hooks (B), copper wire hangers (C), riser clamp (D), plastic pipe straps (E), copper pipe straps (F), flexible copper, steel, and plastic pipe strapping (G, H, I). Do not mix metal types when supporting metal pipes; use copper support materials for copper pipe, and steel for steel and cast-iron pipes.Fittings for DWV-pipes are available in many configurations, with openings ranging from 1 1⁄4" to 4" in diameter. When planning your project, buy plentiful numbers of DWV and water supply fittings from a reputable retailer with a good return policy. It is much more efficient to return leftover materials after you complete your project than it is to interrupt your work each time you need to shop for a missing fitting.
From: The Complete Guide to Plumbing, 978-1-58923-378-2