Detailed explanation of welding materials used for gas welding and gas cutting!
14 Feb 2020
Gas welding and gas cutting are welding and cutting of metal materials by using the heat released by the mixed combustion of combustible gas and combustion-supporting gas as a heat source. There are many types of combustible gases, such as acetylene, hydrogen, natural gas, and liquefied petroleum gas (mainly propane). At present, the most common application is acetylene gas, followed by propane. Welding materials for gas welding and gas cutting Oxygen: Oxygen is a combustion-supporting gas in gas welding and gas cutting. Oxygen cannot burn itself, but it can help other combustible materials burn. Air separation is commonly used in the industry to produce oxygen. The oxygen used for gas welding and gas cutting is divided into two grades according to purity: the first grade purity is not less than 99.2%; the second grade purity is not less than 98.5%. Oxygen can be supplied in a human oxygen cylinder, or it can be piped. The former is flexible and convenient; the latter is safe and stabl...
Safety precautions for spot welding process
10 Feb 2020
(1) The foot switch of the welding machine should have a solid protective cover to prevent accidental operation. (2) The operating point shall be provided with a baffle to prevent the working sparks from splashing. (3) Welders should wear flat-light protective glasses when welding. (4) The place where the welding machine is placed should be kept dry, and the ground should be paved with anti-skid plates. (5) After the welding work is completed, the power supply should be cut off. The cooling water switch should be extended for 10s and then turned off. When the temperature is low, the accumulated water in the waterway should be excluded to prevent freezing.
Factors affecting welding operation process and welding quality
25 Jan 2020
The surface of the workpiece must be cleaned before welding. The common cleaning therapy is pickling, which means pickling in heated sulfuric acid with a concentration of 10% and then washing in hot water. The specific welding process is as follows: (1) Feed the workpiece joint between the upper and lower electrodes of the spot welder and clamp it; (2) Apply electricity to heat the contact surfaces of the two workpieces and locally melt them to form nuggets; (3) Maintain the pressure after the power is turned off, so that the nugget is cooled and solidified under the pressure to form a solder joint; (4) Remove the pressure and take out the workpiece. The main influencing factors of welding quality are welding current and energizing time, electrode pressure and shunt. 1. Welding current and energizing time According to the size of the welding current and the length of the current, spot welding can be divided into two types: hard and soft. A specification that passes a large current in a...
Spot welding is a resistance welding method
19 Jan 2020
Spot welding is a resistance welding method in which a welding piece is assembled into an overlap joint and is pressed between two electrodes, and the base metal is melted by resistance heat to form a welding point. Spot welding is mainly used in the following areas: 1. Lamination of sheet metal stamping parts, such as car cabs, cabins, fish scale sieves for harvesters, etc. 2. Sheet and profile steel structures and skin structures, such as side walls and roofs of trailers, trailer decks, combine harvester hoppers, etc. 3. Screen and space structure and cross reinforcement. During spot welding, the weldment becomes a lap joint and is pressed between the two electrodes. Its main characteristics are as follows: 1. During the spot welding, the heating time of the connection area is short and the welding speed is fast. 2. Spot welding only consumes electric energy, no filler material or flux, gas, etc. are needed. 3. Spot welding quality is mainly guaranteed by spot welding machines. Simpl...
Main points of the butt welding machine
11 Jan 2020
1. Butt welding machine operators must have professional training, be familiar with butt welding machine structure, performance, operating procedures, and master the knowledge of process parameter selection and quality inspection specifications. 2. Before operation, check whether the welding machine is sensitive and reliable, whether the electrical system is safe, whether the cooling water pump system is leaking, and whether the lubrication parts are well filled with oil. 3. It is strictly forbidden to weld steel bars with a diameter exceeding the specified diameter. Butt welding of the main steel bar must be carried out before cold drawing. In order to ensure the quality of welding, cleaning, rust removal and correction should be performed within a range of about 150mm of the tip. 4. When operating, the operator must bring colored protective glasses and hats to prevent arc light from irritating the eyes and molten metal to burn the skin. 5. The butt welding machine should be parked in...
The advantages of butt welding machine are as follows
03 Jan 2020
1. Energy saving. Radiator flash butt welding machine uses two 125KVA welding resistance transformers as the power source, pneumatic compaction, upsetting, and no hydraulic station. Compared with other other 315KVA single-phase AC welding transformers and two 18KVA hydraulic stations, the UN-250AB welding machine can save up to 78250. 2. Low requirements on the power grid. Only 250KVA power grid can meet. 3. High welding accuracy. Programmable controller PLC and imported stepping motor are used to control the flashing process, which can accurately set the amount of burning and the speed of burning; the welding current is controlled by the microcomputer welding controller The center distance error of the chip head after welding can be controlled within ± 0.2mm, which is convenient for the subsequent group welding. 4. Automatic centering function. Ensure that the distance between the two ends of the pipe string and the ends of the two chip heads before welding is consistent, so as to ens...