The gas supply in the chamber design requires extremely high purity of gas, so it is required to ensure good connection performance, high airtightness, high strength, good control performance and high safety during construction. Therefore, the construction should be strictly in accordance with the standards, using high-quality materials.

One. technical requirements

1. Code for Design of Industrial Metal Pipelines (GB50316 -2000);

Code for Construction and Acceptance of Industrial Metal Pipeline Engineering (GB50235 -2010);

3. Code for Construction and Acceptance of Field Equipment and Industrial Pipeline Welding Engineering (GB50236 -2011);

4. Code for Design of Acetylene Station (GB50031 1991);

Code for Design of Hydrogen and Oxygen Stations (GB50177 -2005);

6. Code for Design of Oxygen Station (GB50030 2007);

7. Safety Technical Regulations for Oxygen and Related Gases (GB16912-2008;

8. Code for Design of Compressed Air Station (GB50029 -2003);

II. Engineering design

1. Design of gas cylinder room:

The gas cylinder room shall be provided with solid walls with thickness of 300 cm, explosion doors and explosion vent windows;

Indoor electrical equipment should have explosion-proof function;

Exhaust fans should be installed in the room to keep good ventilation at all times;

Epoxy resin shall be used for self-leveling on the ground to prevent static electricity from being introduced. Explosion-proof doors shall also be grounded.

2. The gas supply system is required to adopt the method of secondary decompression for gas supply. The gas supply manifold is decompressed forthe * thtime. The gas is decompressed from 150kg to less than 15kg, and then transported to each floor through BA stainless steel pipes.

The two-stage pressure reducer is installed at each terminal of each use point to control the input pressure of the instrument. The gas terminal is equipped with a medium pressure ball valve and a pressure indicator. The two-stage pressure reducer accurately adjusts the pressure to obtain stable pressure, which can meet the requirements of the instrument for different use pressures.

3. Uninterrupted gas supply with single cylinder bus or double-sided bus semi-automatic mode fully meets the use requirements of the laboratory. When replacing gas cylinders, the gas cylinders can be replaced through the card sleeve installed under the high-pressure hose;

4. Two incompatible gases (such as combustible gas H2 and combustion gas 02) are placed separately between two cylinders;

5. Hydrogen belongs to flammable gas, so design gas leakage detection alarm device, set evacuation pipeline, lead to the outside of the room, install one-way valve on evacuation pipeline to prevent open fire backflow;

6. The pipeline is laid along the ceiling of the corridor, enters the laboratory, lays along the wall exposed pipe, reaches the branch of each gas point, installs the terminal accessories device, and meets the requirements of beauty and practicality as a whole.

III. Engineering Materials

1. Pipeline, ball valve, clamping sleeve and tee are made of 316L stainless steel, pressure reducer is high purity gas pressure reducer (stainless steel valve core), high pressure hose (connecting cylinder and manifold) is stainless steel bellows,

In the high-pressure hose gas inlet end, configure one-way valve, can prevent the replacement of steel cylinders, hose gas leakage, while avoiding the outside air mixed into the gas path;

2. Pipeline system: All gas pipelines are selected from M-grade 316L stainless steel pipes, so that the gas will not be polluted by the pipeline system in the flow process to ensure the purity of the gas;

3. Terminal: equipped with stop valve and secondary pressure reducer. Stop valve is used to control the opening and closing of each gas circuit; when the instrument needs adjustment and maintenance, it can stop the gas supply of any specified instrument; pressure reducer is used to display and adjust the terminal pressure.

4. Material description of main components:

(1) High pressure relief valve

High pressure relief valve is diaphragm type alkaline pressure valve, parent material is SS-316L, diaphragm and parent adopt hard seal type, parent thread is 1/4NPT, regulating pressure is 25Mpa Mpa, output pressure is stable, suitable for gas analysis instrument, various high purity gas, corrosive gas and toxic gas.

(2) Stop valve

Globe valve, parent material SS-316L, * high operating pressure up to 3000psig, operating temperature range: -231C to 741C, parent design adopts integrated structure, handle type rotary switch, interface type GENL 0K bayonet joint.

(3) Ball valve

The parent material of ball valve adopts SS-316L, * high operating pressure reaches 3000psig, operating temperature range: -231C to 741C, parent design adopts integrated structure, handle type rotary switch, interface form is GENL0K bayonet joint, which can quickly cut off gas flow.

IV. Others

1. The main material of laboratory gas pipeline project is stainless steel seamless steel pipe of 316LBA and EP grade. Seamless welding technology shall be adopted for connection of all gas pipelines. Flange shall be prohibited. All gas pipelines shall be equipped with appropriate control valves on workbench for easy control by test personnel.

2, compressed air gas pipeline for stainless steel, after water removal, oil removal, dust removal after decompression to the laboratory to meet the needs of laboratory equipment work.

3, laboratory gas pipeline system must be equipped with safety pressure relief and regulating valves, equipped with pressure gauges to directly respond to gas inlet and outlet pressure All pressure relief and purge valves are required to be connected to the exhaust pipeline system through pipelines. Evacuation piping is flammable,

Combustion-supporting gas needs to be discharged separately. The evacuation pipeline should have enough flow space, and the pipeline with more than 1/2 diameter should be selected.

4. Safety relief valves should be marked to indicate the pressure release level.

5. All pipe fittings, valves, pressure regulating devices, switching devices, etc. are made of high-quality stainless steel materials and are standard accessories.

6. Pressure regulating device is required to be stainless steel diaphragm type, and high-quality brand products are required. Pressure relief valve for each gas Pressure gauges are special instruments for various gases.

7, all pipeline marked connection of gas and gas flow direction indicator color must be distinguished by different colors, special gas color should be bright and eye-catching.

8, the laboratory pipeline system in the gas pipeline, cylinder, etc. need to provide appropriate grounding protection. Air ducts shall not be in the same trunking bracket as electrical ducts.

9. The gas pipeline shall be fixed with pipe code brackets every 1.5m, and the appropriate bracket position shall be set according to the bending diameter of the gas pipeline;

10. After the installation of the whole pipeline is completed, the pressure test of the whole system shall be conducted according to the Code for Construction and Acceptance of Industrial Metal Pipeline Engineering. After the pipeline system is maintained for 24 hours, the pressure shall not drop as qualified.

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