Ensure the construction team holds all the required certificates and have the rich experience in simillar projects.
Before installation, the oxygen pipline should be strictly processed through acid cleaning, degreasing, according to GB 16912, "Safety technical regulations for oxygen and related gases". Subsequently, purge the pipeline with oil-free dry air or nitrogen.
In case that the pipelines are not to be put into use for a long time after installation, the pipelines should be filled with dry nitrogen for protection against moisture entry and rusting.
Strictly purging, pressure test and air tightness test should be carrid out after the completion of pipeline installation. Purging gas flow rate shall be not less than 20 m/s. Use of oxygen for purging is forbidden.
Welding method for oxygen pipeline shall be argon arc welding, with higher standard than GBJ 235, GBJ 236.
2. During design phase.
When expansion joints are selected for pipeline expansion compensation, measures to reduce radial vibration or displacement during pipeline operation should be fully considered in the design of pipeline direction.
A filter should be designed in front of the constant pressure regulating valve to prevent rust and debris from clogging the regulating valve. After the valve, a section of copper-based alloy or stainless steel pipe with a length not less than 5 times the pipe diameter and not less than 1.5 m, should be connected to prevent fire.
Oxygen pipelines should have as few elbows and bifurcations as possible, and the elbows and reducers of oxygen pipelines with a working pressure greater than 0.1 MPa should be made of stamping flanges. The air flow direction of the bifurcations should be at an angle of 45°~60° with the main air flow direction.
The flange sealing o-ring should be made of red copper or PTFE material.
The oxygen pipeline should be equipped with a static elimination device, the grounding resistance should be less than 10 Ω, and the resistance between flanges should be less than 0.1 Ω.
3. Precautions during the operation.
The oxygen valves shall be operated slowly and thoroughly at one time, the operator standing on one side of the valve.
Use of oxygen for purging and testing is forbidden.
Detailed explanations and regulations on the operation purpose, method and conditions shall be provided in advance.
Manual oxygen valve with a diameter larger than 70 mm is only allowed to be operated when the pressure difference is lower than 0.3 MPa.
4. Precautions during maintenance.
The oxygen pipeline should be inspected and maintained once every 3-5 years to have the rust removed and paint repaired.
Safety valves and pressure meters on the pipeline shall be inspected at least once every year.
Grounding system shall be perfected.
Before commissioning, purging the system until the outlet gas has an oxygen content of 18-23% (deemed qualified).
All valves, flanges, gaskets, pipes and fittings shall be selected in compliance with relative standards such as GB 16912.
5. Other safety precautions.
Raise the attention of construction workers, maitenance personnel and operators on safety issues.
Raise the vigilance at the management level.
Improve the level of science and technology.
Improve the oxygen delivery scheme.