Installation Ⅲ

时间：2016-07-09 10:42:03点击：次

A. Characteristics
Threading of PVC or CPVC pipe  is only recommended  for Schedule 80. The wa l l thickness i s diminished at the point of  threading and  thereby  reduces  the maximum working pressure by 50%. Because of this, threaded pipe should not be used in high pressure systems nor in areas where a leak might endanger personnel. Threaded joints will not withstand constant or extreme stress and strain and must be supported or hung with this in mind. The threading of pipe sizes above 4" is not generally recommended. CAUTION: Using threaded PVC or CPVC products at or near the maximum temperature range should be avoided. Consult your HANJEWEL representative for speciic details.
B. Selection of Materials
• Power Threading Machine
• Threading Rachet and Pipe Vise (if hand pipe stock is used)
• Pipe Dies designed for plastic
• Threading Lubricant (optional)
• Strap Wrench
• Telon* Tape or an approved Telon Paste
• Cutting and Deburring Tool
• Ring Gauge (L-1)
*Trademark of E. I. Dupont
C. Making the Pipe Thread
1. Cutting and DeburringPVC or CPVC pipe should be cut square and smooth for easy and accurate threading. A miter box or similar guide should be used when sawing is done by hand. Burrs should be removed inside and out using a knife or plastic pipe deburring tool.
2. Threading
Threading Schedule 80 PVC and CPVC pipe can easily be accomplished using either a standard hand pipe stock or a power operated tool. Cutting dies should be clean and sharp.Power threading machines should be itted with dies having a 5° negative front rake and ground especially for plastic pipe. Self-opening die heads, and a slight chamfer to lead the dies will
speed the operation; however, dies should not be driven at high speeds or with heavy pressure.When using a hand held cutter,  the pipe should be held  in a pipe vise. To prevent crushing or scoring of  the pipe by the vise jaws, some type of protective wrap such as canvas, emery paper, rubber, or  light metal sleeve should be used. For hand stocks,  the dies should have a negative  front rake angle of 5° to 10°.
A cutting  lubricant such as a soap and water solution or a water soluble machine oil should be used while  the  threads are being cut. PVC and CPVC is readily threaded and caution should be taken not to overthread.

上一篇：Pressure/Temperature Relationship - PVC

下一篇：Installation