The minimum degree of steel plate welding can be, and does it need to be treated as such?

There is no such requirement. There is no restriction on the preheating thickness of the steel plate when welding the steel plate.

According to the first chapter of the "Welding Manual, Welding Methods and Equipment, Volume 1" compiled by the Welding Society of the Chinese Mechanical Engineering Society

The welding of steel plates is based on the design needs to select and weld the steel plates. It is necessary to take into account the needs of the design itself, choose from several aspects such as weight, strength, economy, etc., and also need to take into account the welding technology level of the master. Combining various aspects, the final selection of the thickness of the steel plate is carried out, so there is no standard.

The outdoor ambient temperature of welding is not less than -10 degrees Celsius, the surface temperature of the plate is not less than 5 degrees Celsius, the humidity is not more than 90%, Q345B belongs to carbon steel, the welding performance is good, and there is generally no need for post-heat treatment

Welding is not allowed below minus 20 degrees.

According to JGJ81-2002 Technical Regulations for Welding of Building Steel Structures

When the ambient temperature of the welding operation area is lower than 0, the base metal in the welding area of the component should be heated to more than 20 or more than 20 times the thickness of the steel plate and not less than 100mm, and it should not be lower than this temperature during the welding process.

There is no need to do post-welding heat treatment.

When the construction environment temperature of carbon structural steel is lower than -5°, windproof insulation and preheating measures should be taken. Otherwise, the construction will be stopped.

Basic Specification Requirements:

1) When installing the steel structure at negative temperature, it is necessary to pay attention to the deviation of the steel structure size caused by temperature changes. If the steel structure is built at room temperature and installed at negative temperature, measures should be taken to adjust the deviation.

2) For steel that starts construction at negative temperature, it is advisable to accept open-hearth furnace or oxygen converter Q235 steel, 16Mn, 15MnV, 16MnQ and 15MnVQ steel. Steel should be guaranteed to combat toughness. Q235 steel should have 20 176; d, others should have 40 176; dQualified assurance.

3) Select electrodes and wires for steel structure welding at negative temperatures, and under the premise of satisfying the preset strength requirements, low-hydrogen electrodes with low yield strength and good toughness should be selected, and high-toughness and ultra-low-hydrogen electrodes can be accepted for important structures.

4) The alkaline electrode must be baked in accordance with the provisions of the product delivery certificate before use. After baking qualified, store at 80 100 176; d. In the oven, take it out and put it in the insulation cylinder when you use it, and take it as you go. If the electrode is exposed for more than 2 hours at a negative temperature, it should be re-baked.

The number of baking of the welding rod should not exceed 3 times.

5) The solder must be baked in accordance with the provisions of the factory certificate before use, and its moisture content shall not be greater than. When welding at negative temperatures, the interval between reuse of the solder should not exceed 2 hours, otherwise it must be re-baked.

6) The purity of carbon dioxide for gas mask welding should not be lower than the volume ratio), and the moisture content shall not exceed the weight ratio). When using bottled gas, the use should be stopped when the pressure in the bottle is lower than 1n mm2. When used at negative temperatures, check the nozzle for freezing blockages.

7) High-strength bolts and ordinary bolts should have product certificates, and high-strength bolts should be re-inspected at negative temperature for torque coefficient and axial force, and can only be used after meeting the requirements.

8) The coating used in the steel structure should meet the functional requirements of the painting at negative temperature, and the use of water-based paint is prohibited.

Below -10°C, no!

Problems that should be paid attention to in the welding construction of steel structure:

1. Welding has strict requirements for the performance of steel, and the limit content of carbon should be ensured for steel used in welded steel structures.

2. The matching of welding materials and base metals, the strength of welding materials at the connection of materials should not be too different from the strength of base metals.

3. The requirements of welding for the working environment, that is, no welding on windy days above level 4, no welding on rainy days, and no welding on low temperatures. In this kind of weather, the weld material cools down rapidly after welding, which is easy to cause large residual stress or deformation at the weld, and even cracks.

During the soldering process, the workpiece and solder melt to form a molten area, and the connection between the materials is formed when the molten pool cools and solidifies. In this process, pressure is often also applied. There are many types of energy** used in welding, including gas flames, arcs, lasers, electron beams, friction, and ultrasonics.

If the strength is sufficient, you should prefer 4mm for economy. Carbon steel plate, arc welding with electrode, diameter electrode welding on the line.

If it is stainless steel, it is best to choose tungsten TIG welding.

There is no minimum, no largest, no requirements, what kind of board can be welded, but the welding method is different from the welding equipment.

The problem information of the landlord is incomplete and cannot be judged, and the welding technical parameters are directly affected, such as: welding method, welding current, welding voltage, welding environment and what kind of specifications are used, etc.

What welding machine is used for welding, resistance welding, electric welding, TIG welding?

Summary. The steel used in the low temperature conditions of -10 -273 is usually called low-temperature steel.

Generally, the -10 -196 temperature range is called "low temperature", and -196 -273 is called "ultra-low temperature".

At present, various welding methods used can be used for low-temperature steel welding, such as electrode arc welding, submerged arc welding, tungsten argon arc welding, molten polar gas shielded welding, CO2 gas shielded welding, plasma arc welding, etc.

Consult how to weld steel at low temperatures.

The steel used in the low temperature conditions of -10 -273 is usually called low-temperature steel. Generally, the -10 -196 temperature range is called "low temperature", and -196 -273 is called "ultra-low sock temperature". At present, various welding methods used can be used for Shenji low-temperature steel welding, such as electrode arc welding, buried arc welding, tungsten argon arc welding, molten extreme gas shielded welding, CO2 gas shielded welding, plasma arc welding, etc.

When welding low-slip high-alloy high-strength steel, the same strength as the base metal should be considered on the premise of ensuring that the weld has sufficient toughness, so in addition to containing Ni of 1% and 3%, the welding material generally contains MO and sometimes a small amount of chromium. When the bridge is carefully connected to low-nickel and low-temperature steel, the nickel content of the welding material used should be the same as or higher than that of the base metal, and the carbon content and sulfur and phosphorus impurities in the weld should be reduced as much as possible, and the manganese and silicon should be limited by the letter gauge.

Summary. Hello dear, glad your question.

If the steel structure is minus 10 degrees, construction is not allowed, and even if it is constructed, it is necessary to do thermal insulation measures.

For example, to build a protective shed or to do thermal insulation protection, rock wool is usually used as thermal insulation, because rock wool has better fire resistance.

I hope mine is helpful to you, if you have any questions, please feel free to ask, thank you

At what temperature can the steel structure not be welded What is the specification.

Hello, dear, I am very happy that your problem steel structure is minus 10 degrees, that is, construction is not allowed, even if construction, you also need to want to do thermal insulation measures such as building a protective shed or doing thermal insulation protection, air and often use rock wool as insulation, because the fire performance of rock wool is better, I hope mine will help you, if you have any questions, Huan type wheel welcome at any time to ask, thank you

GB 50755-2012 Steel Structure Engineering Construction Code You go to view this code, there are corresponding regulations and rules.

If my good to you are helpful to crack the source lead, I also hope that you can move your rich little hands to give a thumbs up, thank you