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When installing instruments on-site, the following requirements shall be met: 1. There should be sufficient lighting, and the instruments should be easy to operate and maintain； It should not be installed in areas subject to vibration, humidity, mechanical damage, strong magnetic field interference, high temperatures, severe temperature fluctuations, or corrosive gases. 2. The height of the instrument panel above the ground should be between 1.2 and 1.5 meters. The locally installed display instruments should be placed in a position where the values indicated by them can be easily viewed when operating the valves manually. 3. Before installation, the instrument should be in good condition with all accessories present, and its model, specifications, and material should be checked in accordance with the design requirements. 4. During installation, the instrument should not be struck or vibrated; after installation, it must be secure and level. 5. Instruments that require degreasing according to design specifications must pass a degreasing inspection before they can be installed. 6. Instruments that are to be installed directly on the process pipelines should be installed after the pipelines have been purged but before pressure testing. If it is necessary to install them simultaneously with the process pipelines, the instruments must be removed during the pipeline purging process. The direction indicated by the arrow on the instrument housing should be consistent with the flow direction of the medium being measured. When connecting the instrument to the process pipeline, the axis of the flange on the instrument should be aligned with the axis of the process pipeline, and it should be secured in such a way that the stress is distributed evenly. 7. After the instruments installed directly on the process equipment or pipelines are installed, they should undergo pressure testing along with the process system. 8. The entry openings of junction boxes on instruments and electrical equipment should not face upward to prevent oil, water, and dust from entering the boxes; if this is unavoidable, sealing measures should be taken. 9. The text on the labels of instruments and electrical equipment, as well as terminal numbers, etc., should be written correctly and clearly. The wiring of instruments and electrical equipment shall comply with the following: 1. The wires should be inspected and labeled before wiring. 2. The insulation layer should not be damaged when stripping it. 3. The ends of multi-strand conductors should be tinned or fitted with terminal lugs. When using terminal blocks, the connection between the wire and the terminal block should be made by crimping or welding; the connection point must be even and secure, with good electrical conductivity. 4. Non-corrosive solder flux should be used during soldering. 5. The connection between the cable (wire) and Suiri should be firmly secured, with an appropriate amount of slack left. 6. The wiring should be correct, and the arrangement should be neat and aesthetically pleasing. 7. When instruments and electrical equipment are susceptible to vibration, spring washers should be installed on the terminals. 8. The line compensation resistor should be installed firmly and easily removable, with an allowable tolerance for its resistance value of ±0.1 ohm. Requirements for the installation of temperature instruments: 1. Temperature sensing elements installed on process pipelines with high dust levels should be equipped with protective measures to prevent wear. 2. When thermocouples or thermal resistors are installed in areas subject to severe impact from the medium being measured, or when they are installed horizontally at a depth of more than 1 meter or in environments where the temperature exceeds 700°C, measures should be taken to prevent bending. 3. The sensing surface of the surface thermometer should be in close contact with the surface being measured and secured firmly. When using terminal blocks, the connection between the wire and the terminal block should be made by crimping or welding, ensuring that the connection is even and secure as well as provides good electrical conductivity. 4. The bulb of a pressure-type thermometer must be completely immersed in the medium being measured. Protective measures should be taken for the capillary tube; its bending radius should not be less than 50 millimeters. Insulation measures should be employed when there are significant changes in the surrounding temperature. Installation requirements for pressure instruments: 1. The installation height of pressure gauges or transmitters used to measure low pressures should be the same as the height of the pressure sampling point. Gauge instruments installed in place should not be fixed to process equipment or pipelines that experience significant vibration. 2. When a pressure gauge for measuring high pressure is installed near an operating position, it should be placed at a height of at least 1.8 meters above the ground, or a protective cover should be added to the front of the gauge. Flow meters 1. The installation of orifice plates and nozzles shall comply with the following provisions: Before installation, an visual inspection of the orifice plate or nozzle shall be carried out; the inlet edge of the orifice plate and the outlet edge of the nozzle must be free of burrs and rounded corners, and their dimensional tolerances shall be verified in accordance with the current **standard “Design, Installation, and Use of Throttling Devices for Flow Measurement”** ； The throttling element should not be damaged during cleaning prior to installation ； The sharp edge of the orifice plate or the curved side of the nozzle should face the flow direction of the medium being measured ； For orifice plates or nozzles installed on horizontal and inclined process pipes, if there are drain holes, these holes should be located directly above the process pipe for liquid media, and directly below it for gas and steam media ； The coaxiality and perpendicularity of the orifice plate or nozzle with the process pipeline shall meet the specifications ； The side of the ring chamber marked with a “+” sign should be on the upstream side of the flow direction of the medium being measured; when arrows are used to indicate the flow direction, these arrows should point in the same direction as the flow of the medium being measured ； The inner diameter of the gasket shall not be smaller than the inner diameter of the process pipe. 2. The connections between the positive and negative pressure chambers of the differential pressure gauge or transmitter and the measurement pipeline must be correct. 3. The rotameter should be installed vertically; the length of the straight pipe section upstream of it should not be less than 5 times the inner diameter of the process pipeline, and the process pipelines before and after it must be securely fixed. 4. The center of the target in a target flow meter should be on the axis of the process pipeline. 5. The distance between the pre-amplifier and the transmitter of the turbine flowmeter should not be greater than 3 meters. 6. The installation of electromagnetic flowmeters shall comply with the following provisions. The flow meter, the medium being measured, and the process pipeline should be connected to the same potential level and grounded ； When installed on vertical process pipes, the flow direction of the measured medium should be from bottom to top. When installed on horizontal or inclined process pipes, the two measuring electrodes must not be positioned directly above and below each other along the pipe ； When the diameter is greater than 300 millimeters, a dedicated support should be used for reinforcement ； When in a strong magnetic field, anti-interference measures should be taken. 7. The dial surface of the elliptical gear flowmeter should be in a vertical plane. Level gauges: 1. The float level gauge should be installed so that the float remains in a vertical position. Its installation height should be such that the normal liquid level is at 1/2 of the full scale of the gauge. 2. When using a differential pressure gauge or transmitter to measure liquid level, the installation height of the instrument should not be higher than the lower pressure tapping point. Note: This requirement does not apply when measuring liquid level using double-flange differential pressure transmitters, the blowing method, or pressure transmission via the vaporization of low-boiling-point liquids. 3. The installation of the capillaries in double-flange differential pressure transmitters shall comply with the relevant specifications. 4. The installation of radioactive isotope level gauges shall comply with the following provisions: A construction plan shall be formulated prior to installation, and it shall be strictly implemented ； The safety measures during installation must comply with the provisions of the current **standard, the “Radiation Protection Regulations”** ； Clear warning signs should be placed at the instrument installation location. 5. The installation of load sensors shall comply with the following requirements: The sensors must be installed in a vertical position, and the loading on each sensor should be even ； Buffering measures should be in place when there are shock loads. Analytical instruments 1. The pre-treatment unit should be installed separately and preferably near the conveyor. 2. The discharge pipe of the sample under analysis should be connected directly to the main discharge pipe, which should lead to a safe outdoor location; the collection point of this pipe should be equipped with a drainage device. Control valves, actuators, and solenoid valves: 1. The direction of the arrow on the valve body should be consistent with the flow direction of the medium. Note: When there are special requirements, this rule may not apply. 2. When installing a small-diameter control valve connected by threads for installation purposes, a detachable movable connector must be provided. The actuator should be firmly fixed, and the operation handwheel should be in a position that facilitates operation. 3. The mechanical transmission of the actuator should be flexible, with no looseness or sticking. 4. The length of the actuator linkage should be adjustable, and the adjustment mechanism must operate smoothly and reliably throughout the range from full open to full closed. 5. When the adjustment mechanism can undergo thermal displacement along with the process pipeline, the installation method of the actuator should ensure that its relative position to the adjustment mechanism remains unchanged. 6. The signal pipes of pneumatic and hydraulic actuators should have sufficient flexibility to avoid interfering with the operation of the actuators. 7. The installation position of the hydraulic actuator should be below the regulator. When it must be higher than the regulator, the maximum height difference between the two should not exceed 10 meters; the gas collection point of the pipeline should be equipped with a vent valve, and a check valve or automatic shut-off device should be installed near the regulator. 8. Before installation, the insulation resistance between the coil and the valve body of the solenoid valve should be checked in accordance with the installation and operation instructions.