What does 6GR mean? How to weld?

Pipe 6GR welding definition The axis of the pipe is at a 45° Angle to the horizontal plane, and the position is fixed and not allowed to change. The outer diameter of the barrier ring is about 300mm larger than that of the thick-walled pipe, and it is installed on the outer edge of the thick-walled pipe. The distance from the joint of the two pipes and the end surface of the thick-walled pipe is no more than 13mm. 6 stands for oblique welding position, G stands for groove, the first letter of groove, and R stands for obstacle ring. Alignment and positioning of pipe groups The alignment and positioning of the welded pipe are the key to ensure the welding quality of 6GR and the good forming of the back of the pipe joint. If the groove form, alignment clearance and blunt edge size are not appropriate, it is easy to cause defects such as falling down, welding bulge and incomplete penetration. In order to ensure the amount of staggered pipe, pipe pair connection should be carried out on a special pipe matching device, positioning using rib plate fixed. 6GR operation characteristics and difficulties 6GR pipe has an obstacle ring, and the thickness difference between the inner wall of the two pipes is 6mm. The technical requirement is that the reverse forming of the pipe is flush with the thick-walled pipe. In fact, the reverse forming is a full-penetration fillet weld form, and the backing welding is extremely difficult. Backing welding Backing weld operation main difficulties are the pipe welding position lean back, because of the heat pipe under non-uniform, drop difficult to transition to a weld seam on the back, and by the gravity, the melt drip drip of the molten drop to be able to overcome gravity and groove negative influence of uneven heating on both ends of the up and down, with smooth transition to a molten pool molten drops, both the front and the full weld formation, when the root welding arc is in us Optimal location is the key to realize one-side welding forming, so in front of the welds will play an arc welder to 5 position to adjust current, arc blow force (thrust) to 7 to adjust current position, its role is easy ignition, increase the stiffness of the arc, can make full use of arc blow force of hot metal to the roots of thick wall pipe, make the opposite of forming good. Electrode about 5 mm at six o ‘clock position of arc, arc ignition electrode after slight swing up and down inside the groove, after being root melting molten hole, electrode should be on the top and lower arc rapidly, should be to thick wall tube side electrode Angle, using small Angle zigzag stretch back and forth, action at the request of rapid, uniform, smooth, welder concentration, to “see” and “listen”, “to send “. So-called “look” should pay attention to observe the temperature of the molten pool and fusion of hole shape, pay special attention to observe whether arc length is melting roots and thick wall pipe 1/2 in the inside of the molten pool size requirements, 1/2 in the groove of the lateral, each arc follow up time with molten pool near solidification advisable, follow up quickly, increase liquid pool, liquid metal easily under drip flash formation, follow up too slow, liquid The molten pool is compressed inward, and the liquid metal is not added in time, which is easy to form a depression in the back weld. Generally, the time of liquid metal delivery should be controlled in 1 ~ 1.5s. “Listen” Listen for the “plop” sound at the edge of the arc breaking pipe bevel. “Send” according to the gap contraction in the process of welding, through the appropriate arc length, electrode Angle, welding speed and way to adjust the arc length and molten pool size, the molten iron accurately sent to the root of the groove, three with appropriate, you can achieve a good reverse forming. When the arc is closed, make a molten hole above the molten pool first, and then slowly take molten iron out 10 ~ 15mm backward, stop arc at the side of the groove, to slow down the solidification speed of the molten pool, prevent cold shrinkage hole in the molten pool, and make the joint form a slope, so as to facilitate the next joint. Attention at this time is in the center of the weld molten pool to the welding arc, in order to prevent to produce cold shrinkage cavity, more cannot accept arc in the molten pool directly, or may be on the back of the weld pool surface cold shrinkage cavity, be difficult to repair the defect, when arc pit are still in the red state, in the molten pool below 10 ~ 15 mm slopes arc, and arc welding to accept, at this point temperature of arc crater will gradually rise, Electrode should be along the pre-made molten hole to the top of the groove root, heard “daughter” after a little pause, transverse swing, then back to normal welding, the key point at this stage is the electrode delivery to reach the designated position, replace welding, melt hole to observe gestures to steady, joint USES heat as far as possible, receive to ensure weld reverse side shape is smooth, beautiful. Filling welding After the end of the bottom welding, use the Angle grinder to clean the joint uneven, adjust the arc blowing force (thrust) to the position of 5, use the arc blowing force on both sides of the weld to form the digging effect, effectively prevent slag inclusion. The welding rod is suspended on both sides of the groove. The molten pool is always kept in a horizontal position, and the welding and arc extinguishing points of the adjacent layer should be staggered 10 ~ 15mm to each other. After the completion of filling welding, the welding seam should be 1 ~ 2mm lower than the base metal to facilitate the welding of the cover layer. Covering welding Before welding, adjust the arc blowing force (thrust) to the position of 2, its role is to reduce the arc blowing force, weaken the arc rigid, arc soft, can control the weld edge defects, make the appearance of the weld smooth, improve the appearance quality of the cover layer. The first half of the circle electrode formed in the first overhead welding parts for welding triangle area, with crescent carrying original along the horizontal direction of welding, when the electrode swing to bevel edge, should pause, the status of molten pool in the basic level, after half a circle electrode in lean back arc welding position, once upon a time and a half circle left for welding the triangle area of the tip horizontal pulling to the left to the lower edge of the groove, Make molten pool and the first half of the circle to weld a plug in the beginning part, with the horizontal zigzag original article, article convergent method will be half a circle electrode after shipment to convergent parts for welding area of the tip, the molten pool one narrow, until after fill triangle arc, cover the surface of welding arc and arc parts should be flat, arc before should fill arc crater.铜焊丝,Copper Welding Rods,铝焊丝,aluminium welding wire,镍焊条,Nickel electrode,药皮焊条,Flux Coated Brazing Welding Rods