joint form

SMAW basic joint form butt, lap, fillet and T-. The select joint form, mainly based on the structure of the product, and considering the stress conditions, processing costs and other factors. Butt and lap force uniform save metal, it is most widely used. Butt joints compare the sizes of materials and assembly requirements
Strict.

groove forms

Processed into a certain geometrical shape, the area to be welded in the welding member according to the design or process needs, and the groove by the groove after assembly constituted called. The use of mechanical (cutting, planing or turning), flame or arc (carbon arc gouging), chamfering process called open groove. The open groove the arc to look deep into the bottom of the groove, to ensure that the underlying penetration, ease of cleaning residue, and good weld formation, but also to adjust the proportion of the base metal and filler metal in the weld metal.
Arc beveling form should be based on the structure of the weldment, the thickness and technical requirements optional common groove form: I-shaped, V-shaped, X-shaped, Y-shaped, double-Y shape, a U-shaped groove with a blunt edge, etc. . General butt joint thickness 1-6mm, with I-shaped groove weld on one side or both sides welded to ensure penetration; plate thickness ≥ 3mm, in order to ensure the effective thickness of weld penetration, improve weld forming processed into a Y-shaped, X-shaped, U-shaped and other shapes of groove.
In the plate thickness with the same double-sided groove than the single-sided groove, a U-shaped groove is consumed than the V-shaped groove electrode small, small welding deformation, these advantages become more prominent as the thickness increases. U-shaped groove processing more difficult, groove processing fees, generally used for more important structures.
When different thickness steel plate butt groove side of the thick steel plate thinning treatment, should be the requirements of the relevant standards and technical documents.
The form and dimensions of the groove are generally vary with the thickness and the Shihai welding method, welding position, the amount of heat input. Groove processing methods and the workpiece material. See the national standard of the form and size of the groove GB/T985-1988 "gas welding, arc welding and gas shielded weld groove of the basic form and size."

weld pad

When requirements weld full penetration and only from the connector side welding, in addition to forming side welding welding operation technology, but also can be used to back seam plus Garmnent. The purpose of using theWelding Wire pad is to provide the conditions of the first layer, the metal is deposited over the pad, thereby eliminating the layer of molten metal to leak through the bottom from the joint.
The used pad has four forms: the lining of the backing weld copper liner and non-metallic liner.
1) lining the strip of metal strips on the connector on the back. The first weld combination of both sides of the joint in - starting with the lining of the phase. If the lining of not impede the use of the joint characteristics, can be retained in the original position; otherwise, furring shall be removed out. The lining of the required material to match with the base metal and Welding Rodused in metallurgy.
2) copper gasket copper liner is sometimes used to support the joint underlying weld pool, it applies to straight butt weld. The higher the thermal conductivity of copper, help to prevent the weld metal and the liner fusion.
3) non-metallic liner refractory liner is a scalable Molding jig or pressure-sensitive tape snapping the back of the joint, it is suitable for space curved butt weld. The SMAW method sometimes use this pad. Should be used to follow the specifications recommended by the liner manufacturer.
4) the backing weld backing weld-sided groove weld joints in one or more channel the back of the weld. Weld before the first welds deposited in front of the groove in the connector on the back of Deposited after the bottoming weld is completed, all the rest of the weld groove from the front.