Joining, piping

When a butt or miter groove weld joins pipe component ends of unequal wall thickness and one is more than 1V2 times the thickness of the other, end preparation and geometry shall be in accordance with acceptable designs for unequal wall thickness in ASME B16.25 and ASME B16.5. 

Integrity management processes should take into account the embrittlement effects of dry hydrogen gas on carbon steel pipeline materials and welds used to join pipe sections. 

Thermosetting resin pipe can be joined with mechanical joints or adhesive-bonded Joints. Mechanical joints are generally a variation of gasketed bell-and-spigot joints and may be either nonrestrained or self-restrained. Adhesive-bonded joints are typically bell-and-spigot or butt-and-strap. Butt-and-strap joints join piping components with multiple layers of resin-saturated glass reinforcement. 

Selection of suitable means for joining piping and sealing joints... 

REDUCING FLANGE - A flange fitting used to join pipes of different diameters. 

Union- A plumbing fitting that joins pipes end-to-end so they can be dismantled. 

A gas distribution system can be assembled using compression fittings, similar to those used on domestic water pipes, for pipes of diameter <63 mm. However, fusion joints which caimot leak, are more common. Socket fusion, used to join pipes of sizes up to 125 mm, involves the use of an injection-moulded socket that fits on the pipe ends. A simple socket allows straight continuation of the pipe, whereas 45 and 90° elbows allow sharp corners, and equal tees allow branches to be added. Butt fusion, used to make axial joints on pipes of diameter 63 mm and above, is preferred for diameters >180 mm. 

Butt fusion n. A method of joining pipe, sheet or other forms of a thermoplastic resin wherein the ends of the two pieces to be joined are heated into the lower end of the polymer s melting range, then rapidly pressed together and allowed to cool, forming a homogeneous bond. ASTM D 2657 describes a recommended practice for butt-joining polyolefin pipe by heat fusion. 

The issues affecting the long-term performance of these materials, as well as issues involved with joining pipes and risers are also covered. Finally, the recent trends related to the use of FRP for repair and rehabilitation of deteriorated metallic pipes are presented. 

LCM is found not only in paint, but also in ceramic tiles and water pipes. As stated earlier regarding the historic use of lead pipes in Roman times, the entire pipe was made of lead. In many of the older buildings and institutions in the United States, pipes used in construction were made of galvanized steel and cooper. However, some of the joint materials used to join pipes together used lead-based products. This was the case that was discovered by the Seattle Public School District in 2004 (Buchanan, 2006). 

When mechanical assistance is required to create a joint, there are a few additional considerations to keep in mind. Installers must be sure that the spigot end of a pipe is not inserted too far into the bell end of a pipe. There is some risk of existing joints being damaged if too much force is used to join pipe sections. Many problems can arise if excessive force is used to create a joint. Gaskets can roll up and cause a poor connection. The pipe beU might split. A pipeline might not pass an air test if excessive force is used to create joints. 

When lining a sewer with gasket-joined pipe, the pipe is lowered into the work pit one piece at a time. The pipe sections are joined in the pit and then inserted into the sewer. Don t allow the liner to float within the existing sewer. Equal force should be used as the insertion is made. 

The good mixing of the liquid in the plate and in the join pipe ensures equal concentrafion on the whole column cross section under the device. 

Infrared Brazing (IRB) uses quartz-iodine incandescent iamps as heat energy. For joining pipes typicaiiy. 

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