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operation steps of rotary evaporators

November 3, 2018 by lanphan  

operation steps of rotary evaporators

Step 1: Height adjustment of the rotary evaporator. The rotary evaporator can be raised or lowered manually. When in use, the knob should be controlled: if you turn the knob, the rotary evaporator will rise; if it rotates in the opposite direction, the evaporator will drop. The rotary evaporator can be electrically raised or lowered. If you press the up button, the main unit will rise; if you press the down button, the main unit will drop.


Part 2: The condenser is equipped with two external interfaces, which are used to connect condensate. One external interface is for water inflow and the other external interface is for water outflow. However, it is important to note that the lower the temperature of the condensate, the better the condensation effect. At the same time, the upper interface also has vacuum connection equipment for maintaining the vacuum state.


Step 3: Before starting the rotary evaporator, turn the knob to the minimum value, then press the power button and turn the switch light on. Next, slowly rotate the switch on the right to the desired temperature. In general, the larger evaporation flask speed is maintained at a medium to low speed, and the liquid solvent with a higher viscosity is maintained at a higher rotational speed. The standard interface type of the flask is No. 24, and there are two kinds of bottling, 500ml and 1000ml respectively. During use, you can choose according to your needs. Under normal circumstances, the amount of solution should not exceed 50%.


Step 4: When using a rotary evaporator, first release its pressure, then turn on its motor and evaporate flask. When the trial ends, the motor should be stopped first and the atmosphere should be opened to prevent the distillation bottle from falling off during the rotation.

operation steps of rotary evaporators

October 18, 2018 by lanphan  

operation steps of rotary evaporators

(1) Vacuum:


After opening the vacuum pump, it is found that the vacuum can not be checked. It should be checked whether the bottle mouth is well sealed, whether the vacuum pump itself leaks, whether the sealing ring at the shaft is intact, and the external vacuum tube


A vacuum switch in series can increase recovery and evaporation speed.


(2) Addition:


Using the system vacuum negative pressure, the liquid material can be sucked into the rotating bottle at the feeding port by a hose, and the liquid material should not exceed half of the rotating bottle. The instrument can be continuously fed, and it needs to be charged when feeding.


The first is to turn off the vacuum pump. Second, stop the heating. The third is to slowly open the tube cock after the evaporation stops, to prevent backflow.


(3) Heating:


When using the rotary evaporator, it must be energized before adding water. The temperature control scale is 0-99 °C for reference. Due to the existence of thermal inertia, the actual water temperature is 2 degrees higher than the set temperature.


Left and right, the set value can be corrected when using, for example, you need water temperature 1/3-1/2. Use the connector to remove the power plug.


(4) Rotation:


Turn on the electrical box switch and adjust the knob to the optimum evaporation speed. Take care to avoid fluctuations in the water bath and turn on the cooling water.


(5) Recycling solvent:


First open the feed switch to deflate, then turn off the vacuum pump and take out the solvent in the collection bottle.

Wear cause and repair method of rotary vane vacuum pump

September 29, 2018 by lanphan  

Wear cause and repair method of rotary vane vacuum pump

According to the difference between the rated head and the actual running head of the rotary vane vacuum pump, the outer diameter of the working wheel is reduced by cutting, and the head and flow are reduced to make it consistent with the actual lift.

The design work point of the rotary vane vacuum pump is an effective way to improve the operating efficiency of the rotary vane vacuum pump. Anyone who knows about the vacuum pump will know that the rotary vane vacuum pump is why

The high degree of vacuum is due to the fact that the gap between the rotor and the rotor is very precise, and if the rotor is worn out, it will definitely have a great impact on the performance of the rotary vane vacuum pump. Connect

Attention should be paid to when using electric blast constant temperature drying ovens

September 29, 2018 by lanphan  

  Both of drying oven and bake oven are necessary working machine for production industry. For trolley constant temperature drying oven which can use electric tube to dry the item. Numerous models, while they looks almost same. It mainly include the box, electric heating system, automatic temperature control system and etc. You can use the machine refer to the following precautions:

  they are basically similar

  1. You should put the drying oven in a drying situation and on the horizontal ground.

  2. Install power leakage circuit breaker, choose enough length power wire, and be in tough with the ground.

  3. You can do test and check after the preparation.

  4. When drying, tester can not be array too close. Radiating plate can not be covered.

  5. The drying oven of trolley constant temperature drying oven which has electric contact point mercury thermometer thermostat. The two wire line should join the two terminal above the box.

  6. Join one normal mercury thermometer into the vent valve, and open the hole of vent valve.

 

  7. Adjust the electric contact mercury thermometer to your needs temperature and then fasten the screw of steel cap in order to keep constant temperature. Last but not least, do not put the indicating iron exceed the scale.

How to Use The Rotary Evaporator Safely

September 26, 2018 by lanphan  

How to Use The Rotary Evaporator Safely

Rotary evaporators are primarily used to continuously distill large amounts of volatile solvents under reduced pressure. In particular, the concentration of the extract and the distillation of the receiving liquid in the chromatographic separation can separate and purify the reaction product. The basic principle of a rotary evaporator is vacuum distillation, that is, under reduced pressure, the distillation flask is continuously rotated as the solvent is distilled.

What should you pay attention to when choosing a vacuum drying oven?

September 21, 2018 by lanphan  

What should you pay attention to when choosing a vacuum drying oven?

1. Can the thermometer reading in the vacuum oven represent the actual temperature of the vacuum chamber space?

2. The meter reading of the electric vacuum drying oven is very different from the reading of the glass rod thermometer in the vacuum chamber. Why is this?

3. Why is there no temperature uniformity parameter for the electric vacuum drying oven?

4. How to control the heating temperature under vacuum in the electric vacuum drying oven?

5. Why should the electric vacuum drying oven be vacuumed and then heated?

Precautions for purchasing a drying oven

September 21, 2018 by lanphan  

Precautions for purchasing a drying oven

1. Physical change characteristics of materials - morphology, water content, water content, water of crystallization, particle size, bulk density, viscosity, heat sensitivity, softening point, phase transition point, thixotropy, toxicity, corrosiveness, odor, flammability, explosive Sex, electrostatic, gas permeability, agglomeration, susceptibility to crystals or particles


2. Drying properties of the material - drying curve, critical and equilibrium moisture content under the selected drying conditions.


3. Dry production requirements and long-term planning.


4. The impact of material commodity value and drying effect on it. Such as product moisture, pollution, temperature, wear, crushing, rehydration, etc. on the value of the commodity.


5. Requirements for material recovery rate.


6. The upper and lower sequence process of the material drying process.


7. Drying method of material in the past or drying method of similar products.

Working principle and structure of electric blast drying oven

September 21, 2018 by lanphan  

Working principle and structure of electric blast drying oven Part of the electric heating constant temperature blast drying box is composed of a box body, an electric heater, a temperature controller, a fan, a wind convection circulating air duct, an air inlet duct, an air outlet duct and an air outlet size adjusting device. The electric heating constant temperature air drying oven is heated by an electric heater. Generally, the heating wire exposed in the air is easily oxidized due to high temperature and long-term heating, which affects the life. The Lihui brand dry box heater usually adopts a coil type electric heating tube, that is, a heating wire. Located inside the heating tube, it can reduce the oxidation rate and increase the life, while the heat is transferred to the steel tube to increase the heat transfer area. The drying oven temperature controller is used to control and display the temperature. When the temperature inside the box is lower than the set temperature, the temperature controller controls the heater to continuously heat or the gap heats, so that the temperature inside the box reaches a controllable purpose. The function of the blower fan is to convect the air level in the dry box (desktop electric blast drying oven) or vertical (vertical blast drying oven), so that the air in the box is blown onto the electric heater and heated to the studio. Then, the fan is sucked into the fan by the working chamber and then blown to the electric heating tube for heating, and the temperature in the box is more uniform while continuously circulating and heating.

Electric heating constant temperature air drying oven use and precautions

September 21, 2018 by lanphan  

Electric heating constant temperature air drying oven use and precautions

1. After connecting the power supply, you can turn on the 2 sets of heating switches, and then set the temperature of the control instrument to the temperature you need. The indicator light is on and the blower switch can be turned on to make the blower work.

2. When the temperature rises to the desired temperature, the indicator light is off. At the beginning of the constant temperature, the temperature may continue to rise. This is the effect of residual heat, which will tend to stabilize in about half an hour. In the constant temperature process, the temperature control is automatically controlled by the thermostat in the box without manual management.

3. When the temperature is constant, a set of heating switches can be turned off, leaving only one set of electric heaters to work, so as to avoid excessive power and affect the sensitivity of the constant temperature.

4. The box should be placed indoors.

5. A blade switch of the iron casing shall be installed in the power supply line for the purpose of this box and the casing shall be grounded.

6. Please check the electrical performance of the box before power-on, and pay attention to whether there is an open circuit or leakage.

7. When everything is ready, put the test sample, close the door and unscrew the top exhaust valve. At this point, you can connect the power supply and start working.

8. Do not arbitrarily remove the side door, disturb or change the line. Only when the box fails, the side door can be removed and checked one by one. If there is a major fault, you can contact the factory.

9. This box is a non-explosion-proof drying box, so it has flammable volatiles. Do not put it in a dry box to avoid explosion.

10. Two drying shelves are attached to each drying box. The average load per shelf is 15 kg. Do not over-tighten and overload the test specimens to avoid affecting hot air convection. At the same time, the test piece should not be placed on the heat sink at the bottom of the studio to prevent overheating.

Self-introduction of laboratory drying oven

September 21, 2018 by lanphan  

Self-introduction of laboratory drying oven

Industrial ovens range in temperature from room temperature to 300 degrees and can be arbitrarily selected for permanent temperature control.

The constant temperature oven is equipped with a circulating fan to make the hot air mechanically convect and the temperature is more uniform.

Precision ovens are precision-engineered, well-made and easy to operate.


The box body is machined by CNC machine tool, which is beautiful in appearance and durable.


Double glazed windows with high temperature resistant silicone for easy viewing and reduced heat loss