Standard operation of electrostatic spray gun
November 4, 2021Working accuracy of bending machine
November 5, 2021Hand-held laser welding
Hand-held laser welding are widely used in metal forming ,Sheet Metal Fabrication,Metal Stampings and so on. We hereby wish to instroduce more detail of laser welding.
Diffuse reflection
reflection of mirror
Harmfulness of laser
Radioactivity
Within the allowable range, there is little harm. If radioactive gas or particles enter the human body as an internal source of radiation, it will seriously affect health.
High frequency electromagnetic field
When using high-frequency arc ignition, the intensity of the high-frequency electromagnetic field generated is between 60-110V/m, which exceeds the reference sanitary standard (20V/m) several times. However, due to the short time, it has little effect on the human body. If the arc is frequently started, or the high-frequency oscillator is used as a stabilizing arc device in the welding process, the high-frequency electromagnetic field can become one of the harmful factors.
Harmful gas
During laser welding, the arc column temperature is high. The intensity of ultraviolet radiation is much greater than that of general arc welding, so a large amount of ozone and oxynitride will be produced during the welding process; in particular, the concentration of ozone far exceeds the reference health standards. If effective ventilation measures are not taken, these gases have a great impact on human health and are the most important harmful factor in laser welding.
Safety protection measures
Ventilation device
The laser welding work site must have a good ventilation device to exhaust harmful gases and smoke. In addition to ventilation in the workshop, several axial fans can be installed to exhaust air in places where the welding workload is heavy and the welding machines are concentrated. In addition, local ventilation can also be used to remove harmful gases around the arc, such as laser welding purifiers, fume exhaust welding torches, etc.
Protection ray
Use cerium tungsten electrode with extremely low radiation dose as much as possible. When processing the thorium tungsten electrode and cerium tungsten electrode, the sealed or exhausted grinding wheel should be used for grinding. The operator should wear personal protective equipment such as masks and gloves. After processing, wash hands and face. Store in an aluminum box.
Protection against high frequency
In order to prevent and weaken the influence of high frequency electromagnetic field, the measures taken are as follows:
● The workpiece is well grounded, and the welding torch cable and ground wire should be shielded with metal braided wire
● Reduce the frequency appropriately
● Try not to use a high-frequency oscillator as an arc stabilizing device to reduce the time of high-frequency electric action
Safety protection introduction
The safety measures taken in the structure of the laser and laser hand-held welding machine mainly include:
● Protective cover: used for operators to accept more than the maximum continuous exposure
● Safety interlock: an automatic device connected to the protective cover to avoid radiation when the protective cover is removed
● Key switch: turn on the switch light, the laser will emit light
● Safety light path: close the light path that may cause burning or secondary radiation due to radiation
● Beam termination: In order to make the laser beam not exceed the controlled processing area, use the beam termination program
Personal protection measures
protective glasses
The filter of the protective glasses produced by Honghe Laser selects a specific attenuated laser wavelength and transmits as much unprotected visible radiation as possible for reference.
Protective mask
Mainly used for ultraviolet laser source, 1000 watt fiber laser as an optional device.
protective gloves
High-energy laser light can cause damage regardless of direct or scattered light. It is necessary to wear laser protective gloves.
protective suit
The laser protective clothing produced by Honghe Laser is fire-resistant and heat-resistant, which can be used for reference.