What grade metal to use

[indy4x]

Hi

I need to make some weld in bungs

They will go into 2" OD, 1/4" wall seamless tube and the bungs will have a 1 1/4" × 12TPI internal thread to take a Johnny Joint

I can machine the bungs and cut the thread easy enough

The complete assembly will be part of a 4 link rear axle setup on my Jeep

I can get EN8 or EN3B, I'm leaning towards EN8

Will this be suitable?

 

[doubleboost]

If you are welding it EN3B is a better option .
EN8 is the best steel to machine .

 

[Morrisman]

If you are welding it EN3B is a better option .
EN8 is the best steel to machine .

I've used EN8 for the steering stem and front wheel spindle on my trike. 1" diameter. Should be man enough, it's a pretty strong steel, right? I welded a 'head' on both, seemed to weld okay.

 

[indy4x]

If you are welding it EN3B is a better option .
EN8 is the best steel to machine .

Hence my dilemma because I have to machine it then weld it into the tube

 

[Morrisman]

Hi

I need to make some weld in bungs

They will go into 2" OD, 1/4" wall seamless tube and the bungs will have a 1 1/4" × 12TPI internal thread to take a Johnny Joint

I can machine the bungs and cut the thread easy enough

The complete assembly will be part of a 4 link rear axle setup on my Jeep

I can get EN8 or EN3B, I'm leaning towards EN8

Will this be suitable?

2" OD is some serious size tube for a 4 bar. Whats it for, rock crawling?

 

[indy4x]

I've used EN8 for the steering stem and front wheel spindle on my trike. 1" diameter. Should be man enough, it's a pretty strong steel, right? I welded a 'head' on both, seemed to weld okay.

View attachment 357042

I'd prefer EN8 from a strength perspective

 

[indy4x]

@Morrisman a bit of everything

When I had my Frontera, I did bend the rear arms climbing over rocks

I have all the metalwork to stick on the axles, the crossmember to suit and the Johnny Joints, It is a copy of a yank kit and all designed for the arms being 2" tube.

It is a weld your own kit and so far it's cost me a 1/3rd of the price of a kit from the USA

The bungs were supposed to be included but have been let down

I can get the EN8 for about £80 and thats enough to do 14 bungs with plenty spare as opposed to buying ready-made bungs at £30 a pair

 

[Agroshield]

...I have to machine it then weld it into the tube...

This is not relevant to your original question, but have you a picture or drawing of the finished item? 2" tube with 1/4" wall means 1 1/2" ID. The thread is 1 1/4" OD, so the bush will have only 1/8" (3mm) wall, half that of the tube to which it is welded. Where do the welds go? I guess the threads will need to be chased out with a tap after welding.

 

[indy4x]

@Agroshield

This is the tyle of design that most people use

 

[bricol]

The answer, assuming your EN8 is reasonably recent, is on this very website:

Welding Engineering Steels

 

[indy4x]

@bricol Its on its way, its supposed to be new

Thanks for the link, I had no idea there was a section on steels, very helpful

 

[pint]

Trail Gear use "SAE 8620 Steel"

i have no idea what that translates into

 

[tigdlo]

EN14 is a higher strength weldable steel often used for machined parts of wishbones and similar components.

 

[Agroshield]

I have no idea what that translates into

For comparison or cross reference of the innumerable world material standards, this site is a good starting point: https://equivalentmaterials.com/materials/sae-8620

 

[pressbrake1]

If you are welding it EN3B is a better option .
EN8 is the best steel to machine .

En8 has been the worst steel to machine for a long time as carbon count is lower

 

[pressbrake1]

@Agroshield

This is the tyle of design that most people use

View attachment 357071

I used to make these during my 4x4 manufacturing days
I used en3 as welding is easy , cheap and hydraulic rams prove its durability

 

[pressbrake1]

EN14 is a higher strength weldable steel often used for machined parts of wishbones and similar components.

Good for smaller hydraulic rams that are a bit to long for en3 to survive

 

[Nick DV]

The answer, assuming your EN8 is reasonably recent, is on this very website:

Welding Engineering Steels

Interesting read and have learned something new. Every day's a school day as they say