Pipes forming

Anon., CISHC Chem. Safety Summ., 1984, 55(218), 34-35 Diethylamine fumes from a reactor were usually absorbed in a glass scrubber through which sulfuric acid was circulated, but an unresolved fault in the level sensor caused the acid circulation pump to operate intermittently. While the pump was not running, amine fumes condensed in the dip pipe, forming a sohd crust (of the sulfate) which allowed a quantity of condensed amine to accumulate out of contact with the acid. When the pump was restarted, the neutralisation exotherm was sufficient to shatter the scrubber and distort the mesh guard around it. 

Local dissolution features are recognized in the Delaware Basin. These may be of either shallow or deep origin, and it is the latter which may pose the greater potential hazard to the repository. These features, often called collapse chimneys or breccia pipes, form when localized dissolution occurs deep in the evaporite section, possibly at the base of the salt beds, resulting in a cavern into which overlying beds... 

Proprietary process of Union Carbide, Indianapolis, IN. Not normally available in tubular or pipe form. 

The collective results from the five laboratories for the contamination by Zn from galvanized pipes formed a single group, i.e. there was no statistical difference between the values. However, this was only achieved because the very large scatter between replicates bridged the large difference between means obtained by the different laboratories, see Figure 4.2 (a). 

Only when the body is rejoined in the pressure head, is the pipe formed to a compact column. 

However, recently a biodegradable irrigation pipe formed from a renewable material has been described (7). The biodegradable irrigation pipe is formed having a pipe wall with a plurality of layers. The layers may be fabricated from a core layer sandwiched between inner and outer protective layers. 

The separation column was prepared using a pair of eccentric cod assembhes, which were made by winding a 1 mm l.D. polytetrafluoroethylene (PTFE) tubing onto 7.6 cm long, 5 mm O.D. nylon pipes forming a series of tight left-handed cods. A set of these cod units was symmetrically arranged around the holder hub of 7.6 cm diameter in such a way that the axis of each cod unit is parallel to the axis of the holder. A pair of eccentric coil assemblies was mounted on the rotary frame, one on each side, and seriaUy connected with a flow tube. 

The separation column was prepared by means of a pair of eccentric coil assemblies, which were made by winding a single piece of 1 mm l.D. polytetrafluoroethylene (PTFE) tubing onto 7.6 cm long, 5 mm O.D. nylon pipes forming 20 units of serially connected left-handed coils. 

A number of other polymers are used in pipe form for small markets. Polymethylmethacrylate (PMMA) is popular where high transparency pipe is required for purposes such as demonstration display equipment. PC materials have high strength and stiffness and find some application for short-term pipe-work applications but the material can fail in brittle fashion because of notch sensitivity and crack growth when exposed to hydrocarbons. It therefore finds no long-term, large scale applications. 

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