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Schedule 20 pipes (also called DWVs) are the least rigid PVC pipes. 1/2 inch (1.27 cm) plumbing grade PVC pipes are also extremely flexible, but they lack strength and can kink when bent.
They are suitable for non-pressurized or low pressure plumbing applications like irrigation systems, sanitary drainage, or for construction projects where flexibility is more important than structural strength. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/3\/3b\/Determine-PVC-Pipe-Size-for-a-Project-Step-5Bullet1.jpg\/v4-460px-Determine-PVC-Pipe-Size-for-a-Project-Step-5Bullet1.jpg","bigUrl":"\/images\/thumb\/3\/3b\/Determine-PVC-Pipe-Size-for-a-Project-Step-5Bullet1.jpg\/aid905870-v4-728px-Determine-PVC-Pipe-Size-for-a-Project-Step-5Bullet1.jpg","smallWidth":460,"smallHeight":298,"bigWidth":"728","bigHeight":"471","licensing":"<div class="mw-parser-output"><p>License: <a rel="nofollow" class="external text" href="https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/">Creative Commons<\/a><br>
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<\/p><\/div>"} They works well for kites and other light structures. The actual exterior diameter of a 1/2 inch PVC pipe is not 1/2 inches, but rather 0.840 inches (2.133 cm). {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/b\/b5\/Determine-PVC-Pipe-Size-for-a-Project-Step-6Bullet1.jpg\/v4-460px-Determine-PVC-Pipe-Size-for-a-Project-Step-6Bullet1.jpg","bigUrl":"\/images\/thumb\/b\/b5\/Determine-PVC-Pipe-Size-for-a-Project-Step-6Bullet1.jpg\/aid905870-v4-728px-Determine-PVC-Pipe-Size-for-a-Project-Step-6Bullet1.jpg","smallWidth":460,"smallHeight":298,"bigWidth":"728","bigHeight":"471","licensing":"<div class="mw-parser-output"><p>License: <a rel="nofollow" class="external text" href="https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/">Creative Commons<\/a><br>
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