The ceramic nozzle is used to divert the protective gas, and the shape of the weld appearance is also closely related to the size of the ceramic nozzle. The size of the porcelain nozzle depends on the width of your weld seam and the width of the molten pool. The larger the molten pool width, the greater the protection range required, so the larger the porcelain nozzle is required.
The selection of ceramic nozzle is mainly affected by several factors such as base metal material, base metal thickness, groove angle, current size, and tungsten electrode.
The common ones are flat-mouthed, high-necked, and long-necked.
1) For the mouthpiece of the flat mouth, the length at the depth of the tungsten electrode should not exceed 5 mm. Because there are few shunt holes inside, it is easy to cause partial arc to produce stomatal oxidation when the gas is affected by the airflow.
2) The protruding length of the tungsten electrode of the high-neck nozzle can be more than 5 mm, but not more than 8 mm, because the conductive tip of the high-neck nozzle adopts the characteristics of a large mouth body and a small outlet, which can be used when the air is discharged. Gas compression improves outlet velocity and has better wind resistance.
3) There is no requirement for the protruding length of the tungsten electrode of the long-neck ceramic nozzle, because the long-neck nozzle is suitable for welding of large and thick grooves. The deep V-shaped groove itself avoids the disturbance of the gas, and the length can be adjusted arbitrarily according to the needs.
In addition, the ceramic nozzles used in welding can also be divided into: transparent visible ceramic nozzles, non-transparent ceramic nozzles, and can also be divided into filters with and without filters.
The transparent ceramic nozzle can better observe the pattern forming, forming width and other elements in the welding pool; the non-transparent ceramic nozzle is the same as the transparent nozzle in use.
The ceramic nozzle with filter screen can be uniformly protected by the protective gas, while the uniformity of the protective gas of the ceramic nozzle without filter screen is poor, so it is more sensitive to the base metal that is easily oxidized and is more sensitive to pores (such as Ti alloys,aluminum alloy, etc.) should be welded with a porcelain nozzle with a filter screen.
In the welding selection, the larger the nozzle model, the better the corresponding shielding gas, and the higher the welding forming coefficient. At the same time, the original color of the welding can be guaranteed.
In the bottom welding, the ceramic mouth can be selected below 6, because of the depth of the welding groove, the large ceramic mouth can't go deep, hot metal must be heated with gas thrust and electrode, such as this carbon steel mouth, the gap is 4mm, must use small ceramic mouth, that is, the ceramic mouth below 6 bottom.
When filling, the nozzle does not need to be replaced, try to ensure that the interlayer temperature is not too high, and the oxide is not too much. The temperature should not be too high; if the thickness of the plate exceeds 15mm, multi-layer welding must be used.
When covering the surface, especially the nozzle used for stainless steel, use the nozzle of No. 12 or more as much as possible, and the cover surface can completely protect the welding seam from discoloring.
For special alloys such as stainless steel, aluminum alloy, and Ti alloy, it is more important to protect the environment. Therefore, a ceramic nozzle larger than carbon steel should be used in welding, which can make the color of the weld better.
In order to ensure good weld formation, we should follow the principles when selecting ceramic nozzles:
Material, tungsten electrode, groove angle, current, have great influence on the selection of ceramic nozzle;
Ordinary material general type, special material special type;
Titanium, aluminum, magnesium, copper, and other alloys, select the filter ceramic nozzle;
The diameter of the tungsten electrode is very important, which affects the selection of the ceramic nozzle model;
Small ceramic nozzle for small diameter tungsten electrode, large ceramic nozzle for thick diameter tungsten electrode;
The bevel angle has an influence, choose the right ceramic nozzle, and the welding quality is good;
Use a small ceramic nozzle for bottom filling, and a large ceramic nozzle for covering the surface;
The welding current cannot be lacking, and the porcelain nozzle cannot be arbitrarily matched;
Use a small ceramic nozzle when the current is small, and use a large ceramic nozzle when the current is large;
The selection of ceramic nozzle is mainly affected by several factors such as base metal material, base metal thickness, groove angle, current size, and tungsten electrode.
The common ones are flat-mouthed, high-necked, and long-necked.
1) For the mouthpiece of the flat mouth, the length at the depth of the tungsten electrode should not exceed 5 mm. Because there are few shunt holes inside, it is easy to cause partial arc to produce stomatal oxidation when the gas is affected by the airflow.
2) The protruding length of the tungsten electrode of the high-neck nozzle can be more than 5 mm, but not more than 8 mm, because the conductive tip of the high-neck nozzle adopts the characteristics of a large mouth body and a small outlet, which can be used when the air is discharged. Gas compression improves outlet velocity and has better wind resistance.
3) There is no requirement for the protruding length of the tungsten electrode of the long-neck ceramic nozzle, because the long-neck nozzle is suitable for welding of large and thick grooves. The deep V-shaped groove itself avoids the disturbance of the gas, and the length can be adjusted arbitrarily according to the needs.
In addition, the ceramic nozzles used in welding can also be divided into: transparent visible ceramic nozzles, non-transparent ceramic nozzles, and can also be divided into filters with and without filters.
The transparent ceramic nozzle can better observe the pattern forming, forming width and other elements in the welding pool; the non-transparent ceramic nozzle is the same as the transparent nozzle in use.
The ceramic nozzle with filter screen can be uniformly protected by the protective gas, while the uniformity of the protective gas of the ceramic nozzle without filter screen is poor, so it is more sensitive to the base metal that is easily oxidized and is more sensitive to pores (such as Ti alloys,aluminum alloy, etc.) should be welded with a porcelain nozzle with a filter screen.
In the welding selection, the larger the nozzle model, the better the corresponding shielding gas, and the higher the welding forming coefficient. At the same time, the original color of the welding can be guaranteed.
In the bottom welding, the ceramic mouth can be selected below 6, because of the depth of the welding groove, the large ceramic mouth can't go deep, hot metal must be heated with gas thrust and electrode, such as this carbon steel mouth, the gap is 4mm, must use small ceramic mouth, that is, the ceramic mouth below 6 bottom.
When filling, the nozzle does not need to be replaced, try to ensure that the interlayer temperature is not too high, and the oxide is not too much. The temperature should not be too high; if the thickness of the plate exceeds 15mm, multi-layer welding must be used.
When covering the surface, especially the nozzle used for stainless steel, use the nozzle of No. 12 or more as much as possible, and the cover surface can completely protect the welding seam from discoloring.
For special alloys such as stainless steel, aluminum alloy, and Ti alloy, it is more important to protect the environment. Therefore, a ceramic nozzle larger than carbon steel should be used in welding, which can make the color of the weld better.
In order to ensure good weld formation, we should follow the principles when selecting ceramic nozzles:
Material, tungsten electrode, groove angle, current, have great influence on the selection of ceramic nozzle;
Ordinary material general type, special material special type;
Titanium, aluminum, magnesium, copper, and other alloys, select the filter ceramic nozzle;
The diameter of the tungsten electrode is very important, which affects the selection of the ceramic nozzle model;
Small ceramic nozzle for small diameter tungsten electrode, large ceramic nozzle for thick diameter tungsten electrode;
The bevel angle has an influence, choose the right ceramic nozzle, and the welding quality is good;
Use a small ceramic nozzle for bottom filling, and a large ceramic nozzle for covering the surface;
The welding current cannot be lacking, and the porcelain nozzle cannot be arbitrarily matched;
Use a small ceramic nozzle when the current is small, and use a large ceramic nozzle when the current is large;
