Laser welding machines are commonly utilized for butt welding and repair welding of metal materials. The operating principle of laser welding involves using high-energy laser pulses to heat a small area of the material. The heat energy diffuses from the material surface to its interior, creating a specific molten pool after melting. During the entire process, the materials are kept in a high-temperature state.
So, how can we safely operate a laser welding machine?
Precautions for safe use of laser welding machine
- In the event of an emergency, such as a water leak or an abnormal laser sound, it is crucial to press the emergency stop button immediately and turn off the power supply promptly.
- Before operating the laser welding machine, make sure to turn on the external circulating water switch. This is because the laser system uses a water cooling mode, while the laser power supply uses an air cooling mode. If the cooling system fails, it is strictly prohibited to start the machine.
- It is strictly forbidden to touch any circuit components while the machine is in operation. The circuit is high voltage and has a strong current during laser welding operations, so only trained personnel should operate the machine.
- To avoid eye injury, it is prohibited to look directly at the laser while it is in operation. Additionally, it is prohibited to use external equipment to reflect the laser during operation.
- Do not disassemble any parts of the machine or operate it with the safety door open. Also, do not aim the laser head at any equipment parts.
- To avoid fire and explosion, do not place flammable or explosive materials in areas where the laser light path or beam can reach.
Safety and protection of laser welding machine during laser welding
The laser of a laser welding machine has biological effects, such as the ripening effect, light effect, pressure effect, and electromagnetic field effect, similar to ordinary light.
However, if proper protection measures are not in place or if protection is inadequate, these biological effects can lead to direct or indirect harm to human tissues, such as the eyes, skin, and nervous system.
To ensure the safe and protective use of laser welding, it is important to strictly control laser hazards and to properly implement engineering controls, personal protection, and safety management.
1. Engineering control
Engineering controls refer to structural safety measures taken for laser or laser processing systems, mainly including:
Protective Cover: Used to prevent workers from receiving more than the maximum allowable exposure.
Safety Interlock: A device that automatically connects with the protective cover and prevents radiation when the cover is removed.
Safe Optical Path: Closes the optical path that may cause combustion or secondary radiation by irradiation.
Key Switch: Generally refers to the ability to turn off the laser when the key is removed.
Beam Terminator: To prevent the laser beam from exceeding the controlled processing area, an attenuator can be used as a beam terminator.
2. Personal protection
Personal Protective Equipment (PPE) plays a crucial role in ensuring laser safety. To stay protected, it is important to wear fire-resistant and heat-resistant laser protective clothing, use laser protective glasses that effectively reduce specific laser wavelengths, wear a laser protective mask for UV laser sources, and put on laser protective gloves to prevent damage from direct or scattered laser beams.
3. Safety management
Effective safety management involves establishing dedicated organizations or personnel, clearly defining responsibilities and rights, conducting safety training, and providing ongoing supervision.
Safe operation process of optical fiber laser welding machine
- Prioritize Inspecting the Laser Welding Machine
Before starting a laser welding operation, inspect all parts of the laser welding machine to ensure they are functioning normally. After the operation, check both the machine and the work site to eliminate any potential hazards and guarantee a safe work environment.
- Preventing Fire from Laser Irradiation
Direct exposure to the laser beam or strong reflection can cause ignition and fire. Additionally, the laser contains thousands to tens of thousands of volts of high voltage, which can pose a risk of electric shock. To prevent direct exposure, the optical path system of the laser must be completely enclosed in metal. Additionally, the laser welding worktable must be shielded to prevent radiation.
- Protecting Against Laser-Induced Eye Damage
The laser welding machine uses a high power density (units: g/cm3 or kg/m3) and a thin beam, which can easily cause damage to the eyes and skin. To protect the eyes, professional laser protective glasses must be worn during the operation.
- Preventing Skin Burns from Laser Irradiation
Direct exposure of the skin to the laser beam can result in burns. Additionally, long-term exposure to diffuse reflection can cause skin aging, inflammation, and even skin cancer in the operator. To reduce the effects of diffuse reflection, field operators should wear protective clothing.
Precautions for use of laser welding machine
Laser welding is a process in which a high-efficiency laser single pulse is used to heat specific areas of raw materials. The kinetic energy of the laser radiation source is transferred to the interior of the raw materials through heat conduction, causing the raw materials to melt and form a specialized pool of solution.
Laser welding is a cutting-edge welding method that is particularly well-suited for electric welding of thick-walled raw materials and high-precision parts. It can perform various types of welding, such as butt welding, overlap welding, and sealing welding, with a high depth-to-length ratio, minimal total welding width, small heat-affected area, and minimal deformation.
Laser welding is also faster than traditional electric welding and produces a smooth and attractive finish. Additionally, it requires no post-welding cleanup and produces high-quality results with no air holes. With its accurate operation and small focus spot, laser welding offers a high level of precision and can be easily automated.
How to use laser welding machine properly?
Safety analysis of common problems in proper application of laser welding machine:
1. Preparation before starting the laser welding machine
- Verify that the switching power supply and water circulation system of the laser welding machine are functioning properly.
- Ensure that the steam connection of the machinery and equipment in the system is in good condition.
- Make sure that the surface of the equipment is free from dust, spots, oil stains, etc.
2. Laser welding machine on / standby
Laser welding machine start:
- Connect the switching power supply and turn on the main switch for the main power source.
- Start the chiller and laser generator in the correct sequence.
- Open the argon valve and set the total air flow to the optimal setting.
- Enter the key parameters for the day’s work into the system.
- Begin the electric welding process.
Laser welding machine standby:
- Please withdraw the program flow and turn off the laser generator.
- In sequence, turn off the dust remover, chiller, and any other machinery and equipment.
- Then, close the gate valve of the argon cylinder.
- Finally, turn off the main power switch.
3. Common problems in safety application of laser welding machine
- In case of emergency during the operation process (such as water seepage or an abnormal sound from the laser generator), immediately press and hold the change direction button and quickly disconnect the power supply.
- Before starting the operation, make sure to turn on the external cooling circulating water switch for the laser welding.
- As the cooling water method is selected for the laser generator’s system software and the air cooling method for the laser generator, do not start the operation if there are common faults in the cooling system.
- Do not disassemble or assemble components in the equipment at will and do not weld with the protective door of the equipment open.
- It is forbidden to look directly at the laser or reflector laser with both eyes while the laser generator is in use. To prevent injury to both eyes, face the laser welding head with both eyes.
- Do not place flammable or explosive materials on the laser light path or in areas where the laser can reach, to prevent fire or explosion accidents.
- The laser welding machine’s power circuit is under high voltage and strong current flow during operation. Do not touch the electronic devices in the equipment’s power circuit during work.
- Without proper learning and training, staff are strictly prohibited from operating the equipment.