what advantages does helical welding have for pipe production?

[gil]

for large tubes, what is the advantage of a pipe made with helical welding, compared to the classic longitudinal welding? under attach photos of helical welding tubes for clarity

 

[ragnol]

I'm sure I say a chestnut, it's not my sector and I go "nose."

Perhaps the inclined calandra + welding head occupies much less space than a machine that should work axially.... ?

and the form (or section) is better manageable?

 

[scalva]

Bye.
advantages of finished product I do not know
there are advantages in production as parts from coil and varying parameters of "winding" can vary the diameter

 

[ragnol]

Here, hull correctly expressed what I meant with my last sentence. . .

 

[rinato]

to me they explained that it "betters" the internal pressure, because in case of burst it will have to open itself to propeller, and with difficulty, rather than along a simpler and less straight ostica.

 

[Fulvio Romano]

helical welding can be made a continuous process in which the diameter of the pipe is one of the process parameters. the longitudinal one must necessarily be a batch process.

from the structural point of view the pipes are equivalent because the welding restores the continuity of the material. Moreover for "corti" tubes the longitudinal welding is less stressed than the helical one, so the thing still does not work.

 

[gil]

thanks for your answers.

 

[rinato]

helical welding can be made a continuous process in which the diameter of the pipe is one of the process parameters. the longitudinal one must necessarily be a batch process.

from the structural point of view the pipes are equivalent because the welding restores the continuity of the material. Moreover for "corti" tubes the longitudinal welding is less stressed than the helical one, so the thing still does not work.

"corti" is x 50cm or 2mt?

 

[Fulvio Romano]

"corti" is x 50cm or 2mt?

up to about 500-1000 times the diameter the tube is considered short. I mean all the conduct, not the single piece of course.

the mantle of a pressure tube has a voltage given by (sigmal^2+sigmar^2)^1/2.
the sigmar is directed circumferentially and increases linearly with the radius.
the sigmal is directed longitudinally and increases with the radius square because it is generated by the traction of the casebacks (eg valves when closed).

the longer the conduct, the more the traction of the foundls is discharged on the basement, so the sigmal becomes negligible.

 

[gil]

piping and piping are nothing... .

 

[brn]

is a type of soldering diffused in the high chair pylons or similar.
I never understood why

 

[Calender]

one of the advantages I read on the net is that you can produce a wide variety of diameters with the same size of the tape, however you have a longer cord than the tube, you have more defects related to welding and therefore more distortions/defects related to the cord (the size resents)

 

[gil]

thanks calender, excellent explanation with even video illustration! !
before talking to you I had not thought about the problems of optimizing the sheet and bending of the manufacturers. Now it all seems clear and logical.

It's nice to have this forum where you can learn notions. Thanks again to all those who have taken part in the discussion.

 

[bip]

as someone has already said, the helical welding allows to realize any diameter from the same width of the coil, and allows to vary the section produced by the plant more quickly than if the welding is longitudinal.
We then add that for very large diameter pipes, it also allows to use relatively narrow coils (obviously with very welding cord) simply by adjusting the angle of the propeller.

I have always seen it do for important diameters, where the productions are smaller and being able to vary section easily is more important, although in some cases it happens also on "small" tubes, with diameters of 30-40 mm..
if you have to bend the tubes, it is a disaster, the position of the constant welding is essential to be able to bend the tubes in a repeatable way