ELECTRICAL RESISTANCE WELDING

OCCUPATIONAL SAFETY IN ELECTRICAL RESISTANCE WELDING

 

In general, electric resistance welding is a welding method performed by applying electric current to the work pieces under pressure. Possible dangers and ways of avoiding them in the implementation of this method are described below.

5.1. Potential Hazards Related to Electricity and Prevention Methods

 

During the normal operation of machine there is no electric shock risk. Voltage on the electrode during welding is general between 4V -20 V.  This voltage varies depending on the machine power. However, these machines can be dangerous because they usually operate with a voltage of 2 phases 380 V. It is necessary to pay attention to the cables and connection control tables of machine. During maintenance it is definitely necessary to cut power from the machine. If there is a faulty connection or faulty wiring you must immediately inform relevant persons about this situation.

 

5.2. Hazards Related to Burns and Prevention

During the welding process no indication about heating can be observed in welding area and work piece may be thought to be cold.  When these areas are touched burning may occur. Gloves must be worn to prevent this. In some cases work pieces may be held with tools such as pliers, clips and bits and measures can be taken against burning. Because welding electrodes are hot you should not touch with bare hands.

5.3. Injuries resulting from cutting, crushing and Prevention methods

Electric resistance welding is applied to sheet material cut with guillotine or pressed parts. Edges of these pieces are sharp and burred. To protect from scrapes and cuts caused by such parts is cleaning of work pieces before welding and wearing gloves. In electric resistance welding machine the mechanism that moves electrodes exerts pressure on work pieces as a press. If fingers or hands trapped between electrodes may lead to serious oppression. Therefore much attention should be shown to fingers or hands not to remain between the electrodes.

5.4. Accidents that may occur due to splash of hot metal and Prevention methods

If material and working conditions in spot, seam and projected welding methods are chosen correctly there is no danger of splash of molten hot metal particles. However, because still there may be splash and such splashes may hurt the eyes of welders should it is necessary to use white goggles. Metal particles that may splash also pose a threat to the surrounding combustible materials that can be burned. Such materials should be removed from the welding area and measures must be taken to fire that may occur.

5.5. Accidents that may occur due to poisoning and Prevention methods

If work pieces to be welded in resistance welding are cleared from oil, dirt, rust, paint and etc., less smoke will occur during welding. If there are impurities like oil layer, plastic, paint and zinc etc., on work piece smoke occurs during welding. Although this will not be a problem in a workshop with adequate ventilation it will be a problem for small workshops without adequate ventilation. Special ventilation systems are needed for such workshops.