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When ACD centrifugal pumps leave the factory, they are equipped with special English installation, operation and maintenance instructions that are consistent with the pump serial number. There are also corresponding Chinese translation instructions of the same type for reference. If you need specific drawings and spare parts list, you must refer to the drawings and spare parts list section in the English manual. This note specifically reminds users of some key matters during installation and use, so that users can quickly understand this pump. 1. Precautions for installing pipelines: 1.1 When installing the pipeline, no stress should act on the pump head. The pump inlet and outlet bellows should be fully aligned with the pump head, and the bellows should be installed under pressure. If there is a gap between the bellows and the pump inlet and outlet flange, additional gaskets must be added to eliminate the gap. Do not directly tighten the bellows with bolts. This will cause the pump head to be pulled away by pipeline stress in the cold state. At the same time, all pipelines must be cleaned, degreased, and purged. 1.2 Both the liquid discharge port and the safety valve discharge port need to be piped to the recovery device or to a safe discharge position. The pipe diameter is not less than D15. 1.3 The inlet pipe should be as short as possible. If it exceeds 3 meters, a vacuum pipe must be used. This is because cryogenic liquid vaporizes very quickly at room temperature. After the liquid vaporizes, it is easy for the cryogenic pump to cavitate, and bearings, impellers and other running parts are damaged due to excessive vibration. Therefore, the inlet pipeline requires good insulation. 1.4 Reduce the number of tees, valves, and elbows on the inlet pipe as much as possible. There is an installation flow chart in the installation instructions of the pump. Please install the necessary accessories such as pressure gauges, filters, inlet and outlet valves, outlet stop valves, etc. as required. The diameter of the connected inlet and outlet pipes should be equal to or slightly larger than the actual inlet and outlet diameter of the flange on the pump body. The diameter of the outlet pipe in front of the outlet valve should not be much larger than required, otherwise the outlet pressure may not be displayed correctly. The outlet pressure gauge should be installed between the pump outlet and the outlet check valve. 1.5 The motor must be powered by a frequency converter, and the pump is not allowed to be started without a frequency converter at any time. 2. Important steps for cryogenic pump operation: 1． Please check before test driving: A. The liquid level is sufficient, the liquid level in the tank is more than 3 meters, and the inlet pressure meets the requirements on the pump nameplate. B. Before installing the pump body into the vacuum tank, connect the motor and frequency converter, insulate and wrap the three wires separately, and apply sealant on the outside. Jog the frequency converter to determine the direction of the pump impeller. The impeller rotation is required to be consistent with the volute outlet. If it is reversed, change it on the frequency converter and lock the rotation. C. Set the inverter parameters, refer to the motor parameters on the pump nameplate, set and save the motor power, rated current, frequency range, voltage range and other parameters correctly in the inverter menu. Note that the V/F curve is set to linear. D. Pipeline accessories such as inlet/outlet pressure gauges, inlet/outlet valves, inlet/outlet bellows, inlet filters, check valves, return valves, etc. are correctly installed and degreased. E. Replace the pump body and piping system to ensure that there is no moisture or other foreign matter in the system. 2. Pre-cooling cryogenic pump: 2.1 Make sure the replacement is complete, and then slowly open the inlet valve and return valve. Pre-cool for about 15 minutes. Observe the temperature of the return air measuring point to confirm that the pump is pre-cooled. Half-open the reflux valve and slowly open the outlet valve to 1/3 (for outlet pipe diameters above DN65, due to the large outlet pipe diameter, just open one turn). 3． Start the pump and check that the starting conditions are met. Start the pump. If there is any abnormal sound, stop the pump and check. Then adjust the outlet valve and frequency converter frequency to bring the pump to normal working condition. At this time, attention should be paid to safety to prevent the safety valve from tripping. 4. After stopping the pump, close the inlet and outlet valves and open the return valve. 3. Precautions for use: 1. The motor parameter plate and pump nameplate should be fixed outside the vacuum tank to facilitate the inverter setting. The motor must be powered by a frequency converter and the V/F curve must be set to linear. Parameters such as the maximum current must also be set according to the nameplate. If the frequency converter is not used and set correctly, the pump must never be jogged or run, as this may quickly burn out the motor. 2. The wiring between the pump motor and the frequency converter is best completed before the pump body is placed in the vacuum tank, and then the frequency converter is used to jog the motor to determine the direction of the pump. 4. Maintenance backup items: 1. Commonly used spare parts of the pump body are listed in the spare parts list in the English manual. * Mark out that wearing parts are not covered by the warranty. Please consider ordering some commonly used spare parts after installation and use, especially motor bearings. Due to the use of special materials, the delivery cycle is long.