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E-mail
shxiande@126.com
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Phone
19921388221
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Address
No. 888, Kegong Road, Nanqiao, Fengxian District, Shanghai
Shanghai Xiande Experimental Instrument Co., Ltd
shxiande@126.com
19921388221
No. 888, Kegong Road, Nanqiao, Fengxian District, Shanghai
Confirmation of compatibility of organic solventsBefore conducting the experiment, it is necessary to consult the manual of the xiande-2000A instrument to confirm the compatibility between the components in contact with the medium (such as pipeline interfaces, seals, etc.) and the organic solvents used. Avoid using highly corrosive (such as concentrated acid, concentrated alkali organic solvents) and highly oxidizing solvents to prevent component corrosion, swelling, or aging. If the solvent has special characteristics, it is necessary to contact the manufacturer in advance to confirm whether special accessories (such as PTFE gaskets and corrosion-resistant coating inner liners) need to be replaced.
Parameter setting and calibrationWhen setting parameters such as temperature and pressure according to experimental requirements, it is necessary to strictly follow the rated range of the instrument (such as the upper limit of temperature and maximum pressure) and not operate beyond the range. After using or replacing the solvent, it is necessary to calibrate the temperature sensor and pressure sensor to ensure accurate data, such as verifying the accuracy of temperature display through the boiling point or melting point of standard reagents, to avoid experimental failure or equipment damage caused by parameter deviation.
leak testBefore starting the experiment, it is necessary to carefully inspect the sealing structure of the instrument (such as flange sealing surfaces, valve interfaces) to ensure that there is no wear, deformation, or foreign object attachment. If volatile organic solvents are used, suitable sealing grease (such as silicon-based sealing grease, which should be confirmed to not react with the solvent) should be applied to the sealing surface, and the bolts should be tightened to the specified torque to prevent solvent leakage from causing safety hazards or affecting the stability of experimental vacuum/pressure.
Water quality and solvent isolationCirculating water pumps are only used for water medium circulation and direct contact with organic solvents is strictly prohibited. In the experiment, it is necessary to ensure that there is no leakage in the circulation pipeline between the instrument and the water pump, to avoid organic solvents from infiltrating the water pump chamber, which may cause corrosion of the pump body and damage to the motor. If there is a risk of solvent evaporation in the experimental system, a filter (such as polytetrafluoroethylene material) should be installed at the inlet of the circulation pipeline to prevent solvent vapor from condensing and entering the water pump.
Flow and pressure matchingAccording to the circulation requirements of the xiande-2000A instrument, adjust the flow rate of the water pump (usually recommended to operate within the range of 50% -80% of the rated flow rate of the water pump) to avoid excessive flow causing a sudden increase in pipeline pressure, or insufficient flow affecting heat dissipation/temperature control efficiency. Before the experiment, it is necessary to check whether the inlet and outlet valves of the water pump are open to ensure that the pipeline is unobstructed and there is no blockage.
routine maintenanceRegularly replace the circulating water (it is recommended to replace it every 1-2 weeks, and if the water quality is turbid, it should be replaced immediately), and add rust inhibitors (such as specialized water system rust inhibitors) to prevent pipeline scaling and corrosion. When not in use for a long time, it is necessary to drain the accumulated water in the water pump to avoid freezing and cracking in winter or microbial growth in summer.
Selection of solvent toleranceAccording to the characteristics of the organic solvent used (such as corrosiveness, volatility, viscosity), choose a suitable material for the diaphragm (such as fluororubber diaphragm is suitable for most organic solvents, and perfluorinated diaphragm is suitable for strongly corrosive solvents). It is strictly prohibited to use ordinary rubber diaphragms to prevent diaphragm swelling and rupture, which may cause damage to the pump body or solvent leakage.
Vacuum control and protectionDuring the experiment, it is necessary to gradually adjust the vacuum degree of the vacuum pump to avoid a sudden increase in vacuum degree that may cause solvent boiling or system leakage. If the boiling point of the solvent is low (such as ethanol, acetone), a cold trap (used in conjunction with a low-temperature cooling circulation device) should be installed at the inlet of the vacuum pump to condense and recover solvent vapor, prevent solvent from entering the pump body and corroding the diaphragm, and reduce the impact of organic solvent emissions on the environment.
Operation and maintenance standardsWhen the vacuum pump is running, attention should be paid to noise and temperature rise. If there is abnormal noise (such as metal friction sound) or excessive temperature rise (exceeding the ambient temperature of 40 ℃), the machine should be stopped immediately for inspection to eliminate problems such as diaphragm damage and motor failure. Regularly replace the vacuum pump oil (if it is an oil lubricated type, a specialized vacuum pump oil compatible with the solvent, such as fluorine oil, should be selected), and for non oil lubricated types, the diaphragm surface should be cleaned regularly to remove residual solvents and extend the diaphragm's service life.
Selection of cooling mediumAccording to the low temperature range required for the experiment (such as -20 ℃~room temperature, -), select the appropriate cooling medium (such as ethanol water mixture or specialized low-temperature cooling liquid below -20 ℃, avoid using pure water solution to prevent freezing and cracking of the pipeline), and the cooling medium should be compatible with the piping and heat exchanger materials of the device to prevent corrosion. When adding cooling medium, it is necessary to reach the specified liquid level (usually 1/2-2/3 of the level gauge), and not lower than the liquid level to avoid damage to the pump body due to idling.
Temperature control and system matchingWhen setting the cooling temperature, it is necessary to ensure that it is consistent with the temperature control requirements of the xiande-2000A instrument and not lower than the freezing point of the cooling medium to prevent pipeline icing and blockage. Before the experiment, it is necessary to check whether the circulation pump of the cooling circulation device is working properly and whether the pipeline is unobstructed. If there is a leak in the system, it needs to be repaired before starting to avoid the loss of cooling medium and the failure of temperature control. At the same time, the cooling capacity of the cooling device should be selected according to the heat dissipation power of the instrument, ensuring that the cooling capacity is greater than the heating capacity of the instrument, and avoiding overload operation of the cooling device.
Security protection and maintenanceDuring the operation of the low-temperature cooling circulation device, it is necessary to avoid touching the low-temperature pipelines to prevent freezing damage. The surrounding area of the device should be well ventilated and kept away from heat sources. Regularly clean the dust on the surface of the heat exchanger to improve heat transfer efficiency; When not in use for a long time, it is necessary to drain the cooling medium (if it is a volatile or corrosive medium), rinse the pipeline with clean water, dry it, and store it to prevent pipeline corrosion or residual medium from freezing and damaging.
Ventilation and ProtectionThe experiment needs to be conducted in a fume hood to ensure timely discharge of organic solvent vapors. Operators should wear solvent resistant gloves, goggles, and gas masks (if the solvent is highly toxic) to avoid skin contact or inhalation of solvent vapors.
Leak detection and emergency responseBefore the experiment, it is necessary to use soapy water (or specialized leak detector) to check whether the entire system (instruments, water pumps/vacuum pumps, pipeline interfaces of cooling devices, valves) is leaking. If a leak is found, the relevant equipment should be immediately shut down, and the solvent should be drained before repair. If a solvent leakage accident occurs, the fume hood should be immediately started, and specialized adsorption materials (such as activated carbon, oil absorbing cotton) should be used to clean the leaked solvent. Open flames are strictly prohibited to prevent solvent combustion and explosion.
Equipment linkage and shutdown sequenceAt the end of the experiment, it is necessary to follow the sequence of "first turn off the xiande-2000A instrument heating/low-temperature cooling circulation device → turn off the circulation water pump/anti-corrosion diaphragm vacuum pump → empty the solvent in the system → clean the equipment" to avoid sudden pressure changes or solvent residue caused by improper equipment start stop sequence.