Laboratory equipment maintenance

(1) High temperature equipment

Common high temperature experimental equipment mainly includes muffle furnace, electric oven, drying oven (oven), electric furnace (bright electric furnace and box electric furnace). highImproper use of temperature equipment is prone to fire, explosion, electric shock and other accidents.

1. The rated power of the power distribution socket (board, box) should be matched with the electric heating equipment used, and the seriously aging power line should be replaced in time.

2. Ensure that the temperature control and insulation of the heating equipment are in good condition.

3. When using the heating equipment, leave a sufficient safety distancebetweenflammable and explosive materials and debris.

4. The heating device is controlled to a suitable temperature and an appropriate heating time. Do not use it for a long time at the upper limit of the electric heating device.

5. The operator must not leave the heating equipment at the site of use. Disconnect the power immediately after use.

6. Electric ovens can only be used to dry glass, metal containers and samples that are not decomposed and non-corrosive during heating.Flammable, flammable volatiles such as solvents and oils, or samples and equipment that have just been rinsed with ethanol or acetone.

7. After the high-temperature muffle furnace is used, the furnace should be slowly cooled and then opened to open the furnace door to avoid the occurrence of explosives, glassware quenching and cracking, etc.

8. It is generally not allowed to use an open flame electric furnace in the laboratory. If it is necessary to use it in special circumstances, it must be approved by the school.

(2) High-voltage equipment

The high-pressure equipment commonly used in the laboratory mainly includes autoclaves and high-pressure reactors.

1. Formulate operating procedures and operate in strict accordance with the regulations. To manage by special personnel, establish technical files.

2. Regularly put the pressure gauge of the high-voltage equipment to the technical inspection department for inspection and verification, and the qualified person can continue to use it.

3. The operator must not leave when using it. If an abnormality is found, stop using it immediately and notify the device administrator.

4. Do not turn on the device until the pressure has not returned to normal and the temperature has not cooled.

5. When opening, wear protective equipment and do not face the opening to prevent hot gas burns.

6. Insulated gloves should be used when removing items.

(3) Gas cylinders

1. Common cylinder identification

According to the nature of the filling gas, it is divided into a permanent gas cylinder, a liquefied gas cylinder and a dissolved acetylene cylinder. Steel cylinders containing different gases have Different colors and logos.

2. Gas cylinder safety management

(1) The test gas shall be purchased from the designated gas supplier determined by the school bidding. In principle, cylinders are no longer newly purchased and are leased to gas suppliers.

(2) The user must check the steel cylinder number of the purchased gas and the date of the next inspection, and reject the gas name.Gas cylinders with unclear or uncorrelated marks, unclear cylinder stamp numbers, missing colors, lack of verification marks, etc.

The cylinder is used with a registration card and is hung.

(3) The gas cylinder should be placed in a special place and fixed to avoid knocking down. When carrying, screw the cap on the cylinder and use a special trolley to avoid

The cylinder slipped. During handling, it should be lightly loaded and unloaded to prevent vibration. The oxygen cylinder should be equipped with anti-vibration rubber ring. The cylinder should not be lifted by electromagnetic crane.

(4) Dangerous, flammable, explosive and dangerous cylinders should be placed in the cylinder cabinet and equipped with special alarm devices.

(5) Appropriate pipes should be selected for the gas supply pipeline. Metal pipes must be used for flammable, explosive and toxic hazardous gases, among which acetylene and ammonia are used.

Hydrogen should not use copper pipes.

(6) When using, the cylinder should be placed vertically (acetylene and liquefied petroleum gas cylinders must be placed).

(7) Pressure reducing valves and pressure gauges should be installed before use of gas cylinders. Various pressure gauges should not be mixed. Flammable gas (eg H2, C2H2)valves

The screw is a reverse wire, and the non-combustible gas or the combustion-supporting gas (such as N2 and O2) is a positive wire.

(8) Check the pressure reducing valve before opening the cylinder, rotate the pressure regulating handle counterclockwise until the screw is loose, and the state of the pressure reducing valve is closed. At this time

Open the total cylinder valve and the pressure gauge shows the total pressure of the gas in the bottle. Slowly turn the pressure regulator clockwise until the low pressure gauge shows the experiment

The pressure required. When opening the valve, avoid head or body facing the main valve. When opening or closing the bottle valve, only use a special wrench to slowly enter

Line to prevent static electricity from being generated at high speed. Never use tools such as hammers and pipe wrenches to open and close, so that the valve or pressure gauge is not affected.

Failure. After use, close the main valve and close the pressure reducing valve after the residual air in the pressure reducing valve has escaped.

(9) To avoid collision of the cylinder with other objects, do not knock the cylinder. Gas cylinders should be kept away from heat, fire and electrical equipment and should not be in contact.

A conductor with current flowing through it. Cylinders for combustible and combustion-supporting gases shall not be stored in the same room and shall not be less than 10 m from the open flame.

. Gas cylinders storing easy polymerization or decomposition reactions should avoid radiation, electromagnetic waves and vibration sources.

(10) The gas in the cylinder should have a certain amount of residual pressure and should not be used up to prevent danger from backfilling. Permanent gas cylinder residual pressure is not

Less than 0.05 MPa; the remaining amount of liquefied gas is not less than 0.5% to 1% of the specified filling amount; dissolved acetylene retains residual gas at different ambient temperatures

pressure.

(11) For gas cylinders that are not used temporarily, you can contact the designated gas supplier for free temporary storage. The exhaust gas cylinder should not be disposed of at will

, must contact the designated gas supplier to retired.

2. Centrifuge

(1) All types of centrifuges should be managed and maintained by a dedicated person. High and ultracentrifuges require regular inspection and maintenance. Users should keep detailed records.

Record the experimental status and maintenance. High and low speed centrifuges are easy to operate, read the instructions, familiar with the centrifuge operating procedures

You can use it yourself. The ultra-speed centrifuge has a complicated structure and complicated work procedures. It is prone to accidents due to improper use and needs to be trained by management personnel.

It can be used after training.

(2) The electric centrifuge commonly used in laboratories has a high rotation speed. It is necessary to prevent movement due to unbalance or aging of the test tube pad during operation.

The test bench fell off and caused an accident. Therefore, the bottom of the centrifuge casing should be padded with cotton or test tube pads. If there is noise or vibration of the body, it should stand.

That is, cut off the power supply and eliminate the fault in time; the centrifuge tube must be placed symmetrically into the casing. If there is only one sample, it must be placed in a symmetrical position.

An external quality water test tube.

(3) After the centrifuge tube is broken due to vibration, it is easy to cause a safety accident when the glass fragments are rotated and flew out. So when starting the centrifuge, you should confirm that it is covered.

Turn on the power after the top cover of the centrifuge. After the separation is completed, the centrifuge is turned off, and the centrifuge cover can be opened after the centrifuge stops rotating.

, take out the sample, do not use external force to force it to stop moving.

(4) The centrifuge operation time is generally 1 to 2 minutes, during which the experimenter cannot leave, avoiding unattended conditions.

(5) When using the centrifuge, avoid wearing loose clothing, tie, etc. Long hair should be carefully placed to prevent it from being caught in the centrifuge.

(5) Cryogenic equipment

Common cryogenic equipment mainly includes refrigerators, freezers, vacuum freeze dryers, and cryogenic liquid helium circulation refrigeration systems.

1. Place in a well ventilated place, there must be no heat source, flammable and explosive materials, gas cylinders, etc., and maintain a certain amount of heat dissipation space.

2. Specialized refrigerators with corrosion and explosion protection must be used to store chemicals.

3. It is strictly forbidden to store items other than laboratory supplies, such as food and drink. All chemicals stored in refrigerators and freezers should be standardized.

label.

4. Containers placed in refrigerators and freezers must be sealed. If chemicals are stored, they must be clearly marked with a waterproof pen, their name, owner, and

Time, potential hazards, etc., and regularly clean the refrigerator and remove unwanted samples and reagents.

5. The solution that needs to be lyophilized must be pre-cooled in dry ice to ice and placed in a freeze dryer. Freeze dryer after use

Defrost must be done and the pump should change oil frequently.

6. To understand the low temperature equipment used, the experimenter should wear low temperature gloves and other protective equipment during the operation to avoid frostbite.

7. Adjust the refrigerator or freezer to the proper working temperature according to the performance of the stored chemicals, and stop for a long time due to power outages, etc.

To stop work, the stored chemicals must be transferred and stored in a timely manner.

8. Safety precautions to be taken when using cryogenic materials such as cold traps, dry ice, liquid nitrogen, liquid helium, etc. are:

1 When handling and transferring solid cryogenic materials, wear special low-temperature gloves or use tools such as pliers, shovel, and iron spoon.

To avoid frostbite.

2 When transferring and pouring liquid cryogenic substances, be careful to avoid splashing of low temperature liquid. At the same time, you should wear thick overalls, minus

Less exposed skin area outside. Wear a transparent protective mask to prevent low temperature liquid from splashing onto your face. Wear special low temperature gloves,

Be careful not to wear ordinary labor insurance gloves with more pores. The low temperature liquid sticking to the gloves is not easy to be volatilized due to absorption, and is easy to penetrate.

Causes burns on the skin.

3 When using a large amount of volatile low-temperature substances, pay attention to ventilation, otherwise the large amount of gas generated will reduce the proportion of oxygen in the room.

There is a danger of suffocation when it is heavy.

(7) Fume hood

1. The cabinet inside and below the fume hood cannot store chemicals.

2. Before use, check that the ventilation system and other functions in the fume hood are functioning properly.

3. Operate at least 15 cm from the fume hood; minimize the number of operations in the fume hood and in front of the door

Degree of action to reduce the movement of people in the laboratory.

4. Do not store items that will protrude out of the cabinet or interfere with the opening and closing of the glass window.

5. Items placed in the fume hood should not block the opening of the fume hood and the lower part of the baffle inside the cabinet. The height should be placed on the left and right sides.

Separate from the ventilated countertop to allow airflow to pass underneath and away from sources of contamination.

6. During the experiment, adjust the glass window to the elbow so that the chest is shielded by the glass window. The head and upper body must not be stretched.

Into the fume hood; when not operating, the glass window should be opened 10 ~ 15cm.

7. After each use, the table and instrument must be thoroughly cleaned and the glass window closed. Apparent police should be attached to the contaminated fume hood

Sign board.

8. If the fault is found, immediately close the door and contact the maintenance personnel for inspection. Do not experiment.

(8) Emergency shower eye wash device

1. Care for the emergency shower eyewash device, keep the access channel unblocked, and do not use the shower device when there is no relevant experimental accident (check

Except for repairs).

2. Specialized management, regular maintenance, record, to ensure its performance is intact.

3. In an emergency, the hook on the emergency shower can be pulled to spray and rinse.

4. After use, clean the surrounding sanitation.