roll cage tubes

[Crosley.In.AZ]

I have this roll cage kit from Jegs for my 62 Morris Minor...

I noticed tonight that the tubes have seams inside them.

I know very little about steel tubes..  I am familiar with welded seams in the tubes.. Are their different types of welded seams?

the DOM material I understand.... drawn over mandrel

then there is a  seamless tube or is that DOM ?

I may drag race this Morris and I need some proper tubes in it.

[1FATGMC]

I have this roll cage kit from Jegs for my 62 Morris Minor...

I noticed tonight that the tubes have seams inside them.

I know very little about steel tubes..  I am familiar with welded seams in the tubes.. Are their different types of welded seams?

the DOM material I understand.... drawn over mandrel

then there is a  seamless tube or is that DOM ?

I may drag race this Morris and I need some proper tubes in it.

The DOM I have and that I've seen has the inside seam.  Maybe Sam will check in on this,

Sum

[Crosley.In.AZ]

the seams inside these tubes do not look like a welded seam...

I thought DOM material had no seam inside?

Sam?

[dragrcr50]

it really depends on the source, i buy quite a bit of it out of houston and some you can feel a seam and some you cant, however on the inside you can usually see a line in it.  if it is dom you cant see said seam on the outside if not and it is advertised as elec welded seam you will see a blue color on it on the outside........all of jegs is in fact DOM

[Crosley.In.AZ]

thanks for the information.

I do not see a welded seam (blue)  or any seam on the exterior of the tube.

Sounds like I have the proper tubes

[PeterR]

Are their different types of welded seams?
the DOM material I understand.... drawn over mandrel
then there is a  seamless tube or is that DOM ?

ERW Electric resistance Welded
The majority of tube sold is ERW.   This tube is produced by cold forming a strip of steel into a tube then welding the seam.  ERW tube can be identified by the blue strip down one side of the tube where it has been welded.

CDS Cold Drawn Seamless (sometimes just called seamless)
A solid steel bar is drawn over a mandrel to form a tube resulting in excellent dimensional tolerances and even material properties throughout the tube.

DOM Drawn Over Mandrel
ERW tube is cold drawn through a die and over a mandrel as an extra process to improve surface finish and dimensional accuracy. There may also be heat treatment during the course the drawing process.  This product is a lower cost alternative to CDS, but with similar physical qualities.

[1FATGMC]

Are their different types of welded seams?
the DOM material I understand.... drawn over mandrel
then there is a  seamless tube or is that DOM ?

ERW Electric resistance Welded
The majority of tube sold is ERW.   This tube is produced by cold forming a strip of steel into a tube then welding the seam.  ERW tube can be identified by the blue strip down one side of the tube where it has been welded.

CDS Cold Drawn Seamless (sometimes just called seamless)
A solid steel bar is drawn over a mandrel to form a tube resulting in excellent dimensional tolerances and even material properties throughout the tube.

DOM Drawn Over Mandrel
ERW tube is cold drawn through a die and over a mandrel as an extra process to improve surface finish and dimensional accuracy. There may also be heat treatment during the course the drawing process.  This product is a lower cost alternative to CDS, but with similar physical qualities.

Thanks for the good info Peter   .  Is there any difference in strength between them???

Sum

[SKR8PN]

Crosley.....if you don't already have one, get yourself a copy of NHRA's rule book,and check online for  cage/chassis specs.....

Here is a start for you.  http://nhra.com/tech_specs/ETQuickRef.html

[UGLY OLDS]

Crosley.....if you don't already have one, get yourself a copy of NHRA's rule book,and check online for  cage/chassis specs.....

Here is a start for you.  http://nhra.com/tech_specs/ETQuickRef.html

SKR8PN....Ck yer PM's......