Table of Contents
What is the minimum distance between two weld?
The minimum distance between these two joints should be the one-time diameter of the pipe. So, if your pipe is 4″ NPS the distance should be 4″. If this is not possible, it should not be less than 1½”.
What are the standard requirements on the proximity of welds?
BS 4515 standard specifies the proximity between two welds shall be a minimum of 4X (4-times) of pipe wall thickness.
What is weld proximity?
Purpose of Welding proximity requirement is: 2- To avoid the duplicate of residual stress between two joints which may combine with the load during service, this leads to structural failure due to the total combined local stress exceeding allowable stress.
How close can socket weld fittings be?
In case of SW fittings, you will find them to be quite easy to install. Since it requires around 1/6 inches of gap at the bottom of the gap in order to allow the socket access, it also allow thermal expansion.
What is the root gap in welding?
The root face is approximately 3/8-in. for all commercially welded plate thicknesses. The plate edges must be tightly butted (1/32-in. maximum gap) as with the square butt joint.
What is weld toe?
Toe– The junction of the weld face and the base metal. Leg– The distance from the joint root to the toe of the weld. Face– The exposed surface of a weld on the side from which welding was done. Theoretical Throat– The minimum distance minus any reinforcement between the joint root and the face of a fillet weld.
Why does socket weld need a gap?
A gap between the two pipes in a socket weld means the difference between a good weld and a bad weld. Socket welding gap rings are used to eliminate cracked welds by providing a space for the pipe to expand into as it becomes warmer in temperature. The more heat is applied, the more materials tend to expand and soften.
What is the standard setback for socket weld fittings?
On a socket weld, its 1/16″ and can be established with a special spring. The offset between welds cannot be greater than 1/8″. When welding a slip-on flange, the pipe or fitting is set back from the face of the flange a distance equal to the wall thickness -0″ +1/16″.
What is maximum root gap in welding?
The maximum root opening is approximately 1/8-in. because of the difficulty of refusing the welding flux at the base of the first pass weld. If the root gap is maintained constant for the entire length of the seam, plate up to 3/4-in.
What is the proper measurement of root gap?
Generally as per standard the root gap is 3-4 mm max to have full penetration at joint.
Can you XRAY socket welds?
Prof Crisi, The answer to your question is “NO” because radiographic test can be used on socket welds.
Is a socket weld a fillet weld?
Socket weld (the fillet weld) resists around 1/2 the strength of butt welding. So it is mainly used for small pipeline (Small Bore Piping) with diameters NPS 2 or smaller. Butt weld keeps better strength, good for high pressure or high temperature pipelines.
Why do socket welds need a gap?
The function of the gap is to permit thermal expansion of the pipe. Without the gap, the heat of welding can cause the pipe to expand at a faster rate than the fitting. If the pipe bottoms against the socket fitting, the thermal growth of the pipe strains the weld, possibly producing cracks in the root.
Why do socket welders need a gap?
What is welding root gap?
Root gap – the minimum distance between the ends of the elements to be welded which is measured during the assembly of the butt joint for welding. positioning and measurement taking. Lower the fillet arm 2 or the taper gauge 5 into the groove until they come into contact with the ends of the elements to be welded .
What is the minimum distance between welds?
There’s no Code requirement for the minimum distance between welds. A figure “pulled off the air” that is very used in prefabricating shops and jobsites is that the minimum distance should be three times the pipe diameter. Now, as I said, this figure has been “pulled off the air”, i.e., there’s no sound technical reason to support it.
Does ASME VIII Div 1 address distance between welds?
ASME VIII Div 1 doesn’t address distance between welds at all. And the answer is different for every material. For instance Aluminium 5083 is not affected by welds being close together or on top of each other. Carbon steel is a different story. And then PWHT can be taken into account. Distance between welds can be a very complex topic.
What is the minimum distance between two weld seams?
Recommended distance between two weld seams Most of engineering specifications require minimum 2 inch distance between two weld seams. Some specifications call for 2T, where T is the thickness of pipe. The rational is same as stated above, to allow proper inspections & avoid HAZ overlapping.
What is the minimum distance between butt welds in bs2633?
Hi roystercabral, If you were talking about pipe then BS2633 states:- Para 11. 2 The toes of adjacent butt welds shall, whenever possible, be no closer than four times the nominal thickness of the pipe. And for attachment welds it states minimum distance between toes of welds S to be the smaller of 2 times the pipe thickness or 40mm.