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Precautions before installation: 1. Before installing the instrument, the process pipelines should be purged to prevent ferromagnetic substances remaining in the pipes from adhering to the instrument, which could affect its performance or even damage it. If unavoidable, a magnetic filter should be installed at the inlet of the instrument. The instrument itself does not participate in the purging before commissioning to avoid damage to it. 2. Before installing the gauge in the process pipeline, check for any damage to it, and open the housing to remove the filler that holds the pointer in place. 3. The installation style of instruments can be vertical or horizontal; in the case of vertical installation, it is necessary to ensure that the angle between the instrument’s central vertical line and the plumb line is less than 2° ； If installed horizontally, the angle between the instrument’s horizontal center line and the horizontal line should be less than 2°. 4. The pipes upstream and downstream of the instrument should have the same diameter as that of the instrument; the connection flanges or threads must match those of the instrument. The length of the straight pipe section upstream of the instrument should be 5 times its nominal diameter, while the length of the straight pipe section downstream should be 250 mm or more. 5. Since the instrument transmits signals through magnetic coupling, in order to ensure its performance, no ferromagnetic materials are allowed to be present within at least 10 cm around the installation site. 6. Instruments for measuring gases are calibrated at a specific pressure; if the gas is released directly into the atmosphere at the outlet of the instrument, a pressure drop will occur at the float, resulting in distorted data. Under such operating conditions, a valve should be installed at the outlet of the instrument. 7. Instruments installed in pipelines should not be subjected to stress; the inlet and outlet of the instruments should have appropriate pipeline support to keep them in a state of minimal stress. 8. Special care must be taken when installing instruments with PTFE (polytetrafluoroethylene) linings. Since PTFE deforms under pressure, the flange nuts should not be tightened excessively. 9. For instruments with LCD displays, try to avoid direct sunlight on the display during installation to extend the lifespan of the LCD. 10. When measuring low-temperature media, a jacketed type should be selected. Precautions during installation: 1. Avoid making openings in the instrument at the location of the formed pipes. 2. Pay attention to the length of the straight sections before and after the flow meter. 3. For flowmeters such as electromagnetic and mass flowmeters that require grounding, grounding shall be carried out in accordance with the instructions. 4. When welding process pipelines, the grounding wire should be kept away from the instrument itself to prevent the grounding current from flowing through the instrument and causing damage to it. 5. During process welding, prevent the grounding current from flowing through the capillary pressure tubes of single and double flanged instruments. 6. For medium and high-pressure pressure transfer pipes, if argon arc welding or socket welding can be used, such methods should be employed. When the wind speed is >2 m/s, wind protection measures should be taken; otherwise, flux-cored welding wires should be used. When the wind speed is >8 m/s, wind protection measures are mandatory; otherwise, welding must be stopped. 7. Pay attention to the installation direction of the pressure tapping port for the flow meter’s throttling device. 8. Hot bending of stainless steel pressure transfer pipes is strictly prohibited ； It is strictly prohibited to bend the pressure lead pipe flat. 9. The installation locations of the instrument pressure conduits, air ducts, and wire conduit pipes should be such that they do not interfere with future process operations; they should be kept away from areas subject to high-temperature corrosion, and must be secured firmly ； For the wire conduit leading downward from above, its lowest wiring end should be lower than the wiring inlet end of the instrument it is connected to ； A drip tee should be added at the lowest point of the conduit ； Near the instrument side, Y-shaped or conical explosion-proof sealing joints should be added ； A drain (sludge) valve should be installed at the lowest point of the main air line for the instruments. 10. For the copper gaskets used in instruments, if they have not been annealed, they should be annealed before use. Attention should also be paid to the allowable temperature, medium, and pressure conditions for gaskets made of various materials. 11. Within the on-site instrument wiring box, grounds from different grounding systems must not be connected together; the shielding wires of all instruments should be connected to their respective upper and lower shielding layers separately, and it is strictly prohibited to twist these together for connection. 12. When the instruments are in locations that are difficult to observe or maintain, obtain the consent of Party A before changing their location or installing a platform. 13. Joints are strictly prohibited in the instrument wires; in case of special circumstances, approval from Party A must be obtained, and corresponding records of the work done must be kept. Joints in compensation wires should be made by welding or crimping. 14. Stainless steel welds should be pickled, passivated, and neutralized. 15. Instruments and fittings that require degreasing must be subjected to degreasing treatment in strict accordance with the relevant specifications. After degreasing, proper sealing and storage measures must be taken for these instruments and fittings to prevent secondary contamination during storage and installation. 16. Stainless steel pipelines must not come into direct contact with carbon steel. 17. Galvanized and aluminum alloy cable trays must not be cut or drilled using electric or gas welding; instead, mechanical methods such as toothless saws and specialized drilling tools should be used for cutting and making openings. 18. Stainless steel pipes must not be cut or drilled using electric or gas welding; plasma or mechanical cutting and drilling methods should be used instead. 19. Wiring ducts, cabinets, panels, etc., for instruments with a voltage greater than 36V shall be grounded; the threads of the grounding wiring ducts shall be treated with conductive paste ； The threads of the wiring conduit for instruments with a voltage of 36V or less should at least be treated to prevent rust ； The exposed thread should not be more than one thread. 20. The instrument conduit in explosive areas should maintain electrical continuity. 21. For insulated instrument circuits with voltages below 100 volts, a 250V megohmmeter should be used to measure the insulation resistance of the circuits, with a value of ≥5 megohms. 22. Aluminum alloy cable trays should be bridged with short-circuit wires, while galvanized cable trays should be secured with no fewer than two anti-loosening screws. For trays with a length of 30 meters or less, both ends must be reliably grounded; for lengths exceeding 30 meters, an additional grounding point should be added every 30 meters. 23. When instrument wires of different grounding systems or instrument wires and power wires share the same tray, they should be separated by a metal partition. 24. Gas welding is strictly prohibited in the installation and processing of dashboards, cabinets, boxes, and benches; welding should not be used for fixing them, and mechanical methods should be employed for making openings. 25. The blind ends for instrument heating and return water should not be greater than 100 mm. 26. A pipe cap to prevent valve leakage should be added at the lower outlet of the transmitter drain valve (especially in explosion-proof areas). 27. The instruments, along with their conduit tubes and pressure lead pipes, have one end fixed in a thermally expanding area (such as a tower or accessories that move along with the tower’s thermal expansion), and the other end fixed in a non-thermally expanding area (such as a protective room). When connecting the instruments, it is necessary to take into account the actual conditions on site; the flexible tubes, conduit tubes, and pressure lead pipes must have sufficient allowance for thermal expansion. 28. Tower-mounted cable trays and conduit pipes should be equipped with thermal expansion joints or flexible connections based on the actual conditions on site. Others: 1. For copper pipes, socket welding, sleeve welding, or clamping should be used; for aluminum pipes, sleeve welding shall be employed, and the oxide layer must be removed prior to welding. 2. Special attention should be paid when the measurement pipeline is connected to the measuring instrument. Pipelines for gas media and low-boiling-point liquid fluids should be installed upward ； Pipelines for transporting ordinary liquids should also be laid upward. 3. For the pressure guiding tube used to measure liquids, in order to reduce measurement errors and improve accuracy, it should be laid horizontally for a sufficient distance (greater than 500 mm) outside the container, along the level of the lowest liquid surface. This ensures that the horizontal position at the bottom of the liquid level changes. 4. The pressure guide tube at the bottom of the liquid surface should extend into the liquid container with its opening facing downward, to prevent impurities from blocking it and affecting measurements. 5. Location of the gas outlet above the liquid container. It should be selected in a location where fluid flow and fluid impact within the container can be avoided. After the pressure guide tube is led out of the container, it should be laid vertically upward for a certain height (usually greater than 150 mm), and then laid horizontally. 6. The installation of pressure guiding pipes shall comply with the technical standards for the installation of such pipes in large-scale air separation equipment; the bending radius R of the pressure guiding pipes should be 5D. In the cold box, these pipes shall be installed in accordance with HTA1107-93, Technical Requirements for the Installation of Large-Scale Air Separation Equipment, with a bending radius of R=10D. 7. The materials of the sensing components and pressure transfer tubes of the instruments must meet the material requirements of the process pipelines or equipment; in particular, the sensing components and pressure transfer tubes used for measuring corrosive and toxic media should be checked one by one before installation. 8. The welding technical requirements for the sensor components of the instrument and its pressure guiding tubes must be consistent with those for welding process pipelines or equipment. 9. In tank areas and plant areas where explosion protection is required, special attention must be paid to the relevant explosion protection and grounding specifications when installing instruments. When connecting protective tubes to on-site instruments, instrument boxes, wiring boxes, and distribution boxes, proper sealing is essential, and all work must be carried out in strict accordance with the design requirements.