Lined cylinder pipe

Containers of pyrophoric gases must be kept away from heat, sparks, and open flames in a well-ventilated area. Spark-resistant tools should be used. Use pyrophoric gases only in a closed system designed to withstand the pressure involved. All equipment should be evacuated or purged with inert gas prior to opening the cylinder valve. Use a check valve or back-flow protection device in any line or piping from the container to prevent reverse flow and potential reaction, which could cause a container failure. 

Because of the reactivity of dichlorosilane, reverse flow into the cylinder may cause it to rupture. Always use a vacuum break or other protective apparatus in any line or piping from the cylinder to prevent reverse flow. 

Ojdrovic, R.P., 2013. Asset Management and Repair Prioritization of Prestressed Concrete Cylinder Pipe (PCCP) Lines. In AWWA Distributions Systems Symposium, September 2013. 

Use compatible pipe fittings. (Flammable gas cylinders have valves with left-hand threads cylinders for oxygen and nonflammable gases, except occasionally helium, have valves with right-hand threads. Certain liquefied gas cylinders have two supply lines, one for gas and one for liquid, dependent on cylinder position.)... 

It is very important that the inert gas be available from a reliable source and that the proper pressure and flow rate are always provided. A low-pressure switch and alarm are sometimes installed in the inert gas supply line to the equipment and piping. The alarm will warn the operator that a problem may be occurring with the inert gas supply. The switch is also sometimes interlocked to open up a valve in piping from a backup inert gas cylinder bank. 

The pipe wall thickness is selected to resist the internal pressure, with an allowance for corrosion. Processes pipes can normally be considered as thin cylinders only high-pressure pipes, such as high-pressure steam lines, are likely to be classified as thick cylinders and must be given special consideration (see Chapter 13). 

Valve open too far Internal valve malfunction. Operator error. Calibration error. Operation High N2 pressure at HF cylinders, HF vaporizer - HF vaporizer vessel rupture - HF released to environment. High HF flow to HF vaporizer - high HF flow to B-l wing -potential liquid HF to B-l wing. Local pressure indication on N2 line. Local pressure indication between rupture disk and PRV-4 at vaporizer. PRV-3 at V-13 outlet. PRVs on N2 feed lines to HF cylinders. PRV-4 at HF vaporizer. ii If N2 line relief valves lift, vaporizer relief valve should not lift. Relief valve discharges piped to D-wing stack. 

In the batch process wide iron cylinders are used as chlorination vessels (of some 2.5 cubic meters content) the cylinders are rubber-lined and cooled by a coil made of rubber-lined steel or PVC. The vessels are filled with an 18% hydroxide solution and the chlorine enters the solution through PVC pipes under cooling and stirring the pipes end in distributors which are placed just above the bottom of the chlorination vessel. The vessels are closed by covers, and tail gases arc sucked off and led above the roof of the building. 

The process for manufacturing seamless line pipe is shown schematically in Figure 5.8. In this process, a heated metal cylinder is pierced and then formed into the proper diameter and wall thickness. Seamless pipe is available through 26 in. (660 mm) diameter, but it is normally used only up to 16 in. (405 mmi diameter. Although seamless line pipe is the most expensive (15 to 25% above ERW), it is the most reiitable Even so, failures do occur. Hydrostatic test records reveal that about one failure occurs every 500 mu (800 km) of test. Some mills produce seamless pipe that has a significantly higher failure rate thus, it is important to ensure adequate quality control. 

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