Precautions for safe operation of glass electric melting furnace
1 Safety issues of all electric furnaces
1.1 Electric shock
The all-electric glass melting furnace uses electrodes to input electrical energy into the molten glass. The ions in the molten glass generate heat during the conduction process, and the purpose of melting the glass is achieved through this heat. Therefore, the main reasons for electric shock are as follows:
(1) Touch the wires and copper and aluminum bars for power transmission. Mainly divided into the following two situations:
The first situation is from the power grid to the transformer in front of the furnace or before the magnetic adjustment. The higher voltage of this part is generally 10 kV, or 380 V or 220 V. This voltage is much higher than the 36 V safety voltage that the human body can withstand, and the risk of electric shock here is very high.
The second situation is from the transformer in front of the furnace or the magnetic regulator to the load electrode, silicon molybdenum rod, silicon carbide rod, etc. The voltage of this part is generally lower than the voltage before the transformer in front of the furnace, but it is also much higher than the 36 V voltage for human safety. And because this part is all distributed around the furnace, it is more likely to be encountered during furnace operation and maintenance.
(2) There is a risk of electric shock when touching the electrodes, silicon carbide rods, silicon molybdenum rods, etc. used for the load.
(3) Risk of electric shock when touching glass liquid. Because molten glass is electrically conductive, as long as one part of the molten glass in the furnace is charged, it is considered that the molten glass in the entire furnace is fully charged. Therefore, no matter where you touch the glass liquid, there will be a risk of electric shock.
(4) Examples of safety accidents in glass factories.
When measuring the thickness of the raw meal layer in the melting tank, a worker in a factory used iron tools to insert into the melting tank and was exposed to the molten glass. He was instantly electrocuted. After the electric shock, the worker fell into the furnace and died.
When a factory was replacing the screed tube of the forehearth, the operator's foot touched the silicon carbide rod of the forehearth space heating body, and fell from a height after getting an electric shock and died.
1.2 Burns
(1) The wall of the furnace or other accessory equipment is scalded.
Since the temperature of the molten glass inside the all-electric glass melting furnace is as high as 1 400 ～ 1500 ℃, the temperature of the furnace wall will also be as high as 100 ～ 400 ℃, and the surrounding ancillary equipment or reinforcing steel may also experience high temperatures. If someone touches these high-temperature objects, they will be burned.
(2) Burns from molten glass.
Some artificially formed manufacturing companies need to manually pick out the molten glass for blowing or pressing. Once improper operation touches the human body, severe burns will occur. Manufacturers of mechanical supply, forming workers are prone to burn accidents due to close operation with molten glass during operation. When slagging or discharging the furnace, there may also be accidents of molten glass scalding people. If the furnace leaks or water enters the furnace, an explosion will cause a major accident.
1.3 Damage caused by mechanical equipment
There are many mechanical equipment in the glass melting furnace production line, such as the crane in the workshop, the crusher, belt conveyor, bucket elevator in the batching system, the distributor of the melting furnace, the forming equipment such as the row machine, the press, the bottle conveyer, and Equipment such as annealing and melting are equipment that operates continuously or intermittently. Improper operation or protection may cause injury.
1.4 Glass puncture
It is mainly broken glass products, waste glass produced in the production process, etc., which have sharp ports, and punctures or cuts caused by improper protection.
2 Countermeasures to prevent these safety issues
2.1 Design considerations
In terms of prevention of electric shock, in the design, consider separating the equipment and wires from the power grid to the front transformer or magnetic tuning section with a safety net or a separate room from other equipment for protection, and only allow electrical professional operators to enter and follow professional specifications operating.
The wires from the transformer or magnetic regulator in front of the furnace to the load electrode, silicon molybdenum rod and silicon carbon rod section must be wrapped with insulating material and cannot be exposed. Currently, the commonly used insulation protection includes insulating paint, asbestos cloth, insulating cloth, etc.
Electrodes, silicon carbide rods, silicon molybdenum rods and other charged heating elements must have an insulating protective net to prevent anyone from touching them. Electric shock caused by contact with glass liquid mainly pay attention to the following aspects:
(1) The tools for measuring the thickness of the raw material layer in the melting pool must be insulated;
(2) When there is a material leakage, the power needs to be cut off immediately;
(3) Before the molten glass flows out of the forehearth, the grounding device is used to shield the voltage of the molten glass to ground, so that the molten glass is not charged. It is commonly used to insert the molybdenum electrode into the molten glass and ground the molybdenum electrode to shield the voltage in the molten glass. Note that the length of the molybdenum electrode inserted into the molten glass is greater than 1 /2 of the width of the forehearth;
(4) In the production mode of manual picking and blowing or pressing, insulation measures should be made on the ground of the worker's operating position, and insulating boards or insulating rubber sheets, insulating boards, etc. should be laid.
All electric furnaces must be equipped with a safety alarm system, which monitors the temperature of the circulating water system, the air-cooling system and some key parts at any time. Once there is an abnormal phenomenon, there will be an audible and visual alarm function to prompt the maintenance personnel for maintenance. At the same time, an emergency water source is set around the furnace, and a glass liquid storage tank is designed below the furnace. Once there is a leakage, the glass liquid can not flow freely, causing damage to other equipment and personnel.
The surrounding area of ??the furnace and the corresponding equipment should be set with warnings such as “live hazard”, “do not touch with electricity”, “high voltage hazard”, “high temperature do not touch”, “prevent scald”, “prevent stabbing”, “safety when moving machinery” Signs play the role of reminders.
2.2 Precautions for safe operation during furnace operation
(1) When furnace maintenance or repair personnel need to operate near the furnace, they must wear insulating shoes, insulating gloves and other labor protection equipment.
(2) Blowing workers or molding operators must wear insulating gloves and insulating shoes when they may touch the molten glass, or take insulation measures under their feet.
(3) When the equipment is powered off and retransmitted, the operator in front of the furnace must be notified in advance, and the electrical equipment (such as the electrode system) that has been operated must be inspected, and the surroundings of the equipment must be inspected once.
(4) When an emergency occurs in the melting area or an accident that may seriously threaten personal safety or equipment safety, the operator should quickly press the "emergency stop button" to cut off the power supply of the entire electric melting furnace.
(5) Anyone is not allowed to go on the workbench without insulation protection, and it is not allowed to use conductive objects to touch the furnace wall, conductive equipment and molten glass.
(6) The tool for measuring the thickness of the raw material layer at the feeding port must be insulated.
(7) During the initial operation of the electric melting furnace, the operator of the electric melting furnace should check the electrode softening water system once an hour, and deal with it immediately if it encounters the water cut of individual electrodes.
(8) In the event of a material leakage accident in the electric furnace, the power should be cut off immediately, and a high-pressure water pipe should be used immediately to spray the material leakage to solidify the glass. At the same time immediately notify the leader on duty
(9) The melting pool must be operated in accordance with the power-off regulations after power outage for more than 5 minutes.
(10) Power cut operation is carried out in accordance with the principle of "who is responsible for the power cut, who is responsible for the power supply", and when the furnace needs to be cut off for maintenance, an obvious sign "in operation, no closing is allowed" at the power switch of the cut off ".
(11) When the water-cooling system and air-cooling system alarm, a special person must immediately investigate the alarm and deal with it in time.
(12) The maintenance personnel of the electric furnace must inspect the furnace in accordance with the inspection requirements
Wechat Us 
