Requirements for oxygen pipe

Oxygen pipe requirements:1. The pipe material.Oxygen pipe materials should be determined by the pressure of oxygen, temperature, oxygen flow velocity in the pipe and other conditions.Oxygen pipeline besides meeting the strength condition same as other pipe, it also needs to have the requirement of anti-corrosion, rust prevention and fire prevention.A. Considering the temperature, oxygen pipe under the condition of normal temperature generally USES steel pipe.But in oxygen generating device, due to the steel under -40  has cold brittleness, so for the pipeline working under low temperature should adopt the aluminum alloy, copper alloy or stainless steel, these materials still have good strength and toughness at low temperature.B. Considering the stress condition, oxygen pipeline working pressure greater than 3 million MPa uses brass tube or copper tube.Pressure less than 3 million MPa generally adopts seamless steel pipe, in order to avoid the hyperbaric oxygen flow in the pipes in high-speed flow of wall friction and the possible existence of tiny air pipe causing burning, therefore the oxygen flow rate on carbon steel pipe should be limited.Oxygen under certain conditions, especially under high pressure, friction, impact and spark are likely to react with carbon in the steel and for oxygen pipe, according to the pressure and ways of laying on the downstream side of the pressure or flow control valve group, a length of more than five times the pipe diameter should be adopted, not less than 1.5 m stainless steel tube (GB2270-80) or copper alloy tube; On the downstream side of the oxygen tossing in the working pressure is greater than 0.1 MPa oxygen radiation section, also should use stainless steel pipe.

2. Control flow within 6 - 8 m/s.About the oxygen flow rate control, GB50030 are prescribed in the specification of oxygen plant design:Oxygen working pressure ≥ 10.0 MPa, velocity ≤ 6 m/s;Oxygen working pressure 0.1 ~ 3.0 MPa or below, velocity less ≤ 15 m/s;Oxygen working pressure ≤ 0.1 MPa, the velocity is determined by the pressure drop allowed by the pressure piping.

3. Ungrease treatment of related equipment, pipelines, valves and pipe fittings.Oxygen pipe and accessories, valves should take ungrease treatment processing.Degreasing method is as follows: carbon steel pipe, stainless steel pipe with trichloroethylene skim, skim the thick cloth degreasing agent in tube cleaning or irrigation, into the solvent to more than 50%, and constantly rolling for 15 minutes, fill in defatted record after degreasing qualified.After preview of qualified professional inspectors, with supervisory selectiving examination, spot-check qualified after pipe installation. After degreasing, blow dry the inner pipe with nitrogen or dry air.Ungrease inspection methods: irradiation with ultraviolet lamp pipe wall, if no purple blue fluorescence, qualified.Instruments used: 12W mobile UV lamp, 3650A UV U-shaped tube.Degreasing agent oil content requirements: oil 100 ~ 500 mg/l only for rough skim, > 500 mg/l may not be used, use degreasing agent must use analysis of oil content less than 0.03%.Oil content inspection: not regular sampling sent to special inspection department testing.After descaling, degreasing pipeline application of the plastic will be sealed tube end, to prevent contamination.

4. Electrostatic grounding.Flammable and combustible gas pipelines, in order to eliminate the gas flow in the tube wall due to the pipe friction caused by static electricity, need to be earthed.