i have a lenght of aluminium pipe that have to be bend

spec are 6061t6 2in diameter schedule 40 ( 0.154in wall thick )

my question is what minimum bend radius an alu pipe of the above spec should
be

is there any trick for bending this type of alloy and temper without
cracking the pipe

the problem is that i allready bought and cut to lenght the pipe

it will be bend on a real pipe bender not on a homemade jig

any info appreciated

nanotech1 wrote:
i have a lenght of aluminium pipe that have to be bend

spec are 6061t6 2in diameter schedule 40 ( 0.154in wall thick )

my question is what minimum bend radius an alu pipe of the above spec should
be

is there any trick for bending this type of alloy and temper without
cracking the pipe

the problem is that i allready bought and cut to lenght the pipe

it will be bend on a real pipe bender not on a homemade jig

any info appreciated


I bent some 1" sch 40 in a 180 degree bend with 4" radius using a set of
wooden dies in a small hyd press. I annealed the tubing in my barbeque
for an hour on high, it was like butter but it workhardened up nicely
after bending.
If you are going to bend it more than 20-30 degree you will probably
want to anneal it, the T6 condition may crack past that. You also want
to go minimum 2x dia for a bend radius, but 4x would be better.

In article , nanotech1
wrote:

i have a lenght of aluminium pipe that have to be bend

spec are 6061t6 2in diameter schedule 40 ( 0.154in wall thick )

my question is what minimum bend radius an alu pipe of the above spec should
be

is there any trick for bending this type of alloy and temper without
cracking the pipe

the problem is that i allready bought and cut to lenght the pipe

it will be bend on a real pipe bender not on a homemade jig

any info appreciated



A hydraulic pipe bender should already have a die shoe with the correct
radius of bend for that pipe.
I know mine does.

I have done 2" 6061 in mine and it bent fine.

"Ernie Leimkuhler" wrote in message
...


A hydraulic pipe bender should already have a die shoe with the correct
radius of bend for that pipe.
I know mine does.

I have done 2" 6061 in mine and it bent fine.

Was it T6? I thought T6 was not really good to cold form as it is pretty
hard.

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.

In article , Roger Shoaf
wrote:

"Ernie Leimkuhler" wrote in message
...


A hydraulic pipe bender should already have a die shoe with the correct
radius of bend for that pipe.
I know mine does.

I have done 2" 6061 in mine and it bent fine.

Was it T6? I thought T6 was not really good to cold form as it is pretty
hard.

Yes it was T6-6061.
The pipe benders have a very generous radius to the die shoes so it can
handle it.

6063 is always better for bending if you have the option.

a 4x bend radious 'should' work. A couple of things to think about: 6061
age hardens, if the material is fresh (months old) is will be
appreciably easier to bend than older (years) old. It also has a huge
springback, figure on overbending by at least 5 degrees. Annealing it
will do wonders.

nanotech1 wrote:

i have a lenght of aluminium pipe that have to be bend

spec are 6061t6 2in diameter schedule 40 ( 0.154in wall thick )

my question is what minimum bend radius an alu pipe of the above spec should
be

is there any trick for bending this type of alloy and temper without
cracking the pipe

the problem is that i allready bought and cut to lenght the pipe

it will be bend on a real pipe bender not on a homemade jig

any info appreciated

i need two 90deg bent on this pipe

the radius of bending wont be below 10 inchs for 90 deg angle

do i have to anneal if so how do i do it ?

if i have to anneal whats the best easy way to gauge the final temp of the
aluminium

nanotech1 wrote:
i need two 90deg bent on this pipe

the radius of bending wont be below 10 inchs for 90 deg angle

do i have to anneal if so how do i do it ?

if i have to anneal whats the best easy way to gauge the final temp of the
aluminium



I would try a short length of material first and check for cracks and
deformation. You should also be able to tell by the amount of pressure
required to bend it. The 1" tubing I bent barely even registered on a
10t jack in the press. When I annealed the tubing in the barbeque the
temp gage registered around 600 degree F. I put the tubing lengthwise
on the BBQ and teh slot in the cover for the rotissery was just the
right size to let the cover sit down fully. It might sit up a bit with
the larger tubing but a bit of tinfoil wrapped around it should keep the
heat in. I didn't notice any sag or distortion of the tubing, even
after an hour.

nanotech1 wrote:

i need two 90deg bent on this pipe

the radius of bending wont be below 10 inchs for 90 deg angle

do i have to anneal if so how do i do it ?

if i have to anneal whats the best easy way to gauge the final temp of the
aluminium

If I had to do this, I would try to bend a sample bend on a spare bit
of the same size stock before I would anneal anything, assuming a bender
with appropriate dies was available.

To anneal aluminum to near a dead soft condition, the cheap and dirty
way is to soot the part with an oxy-acetylene torch flame, using just
acetylene, then use the oxy-acet flame to heat the part until the soot
buns off. You can quench it or not, it wont make much difference other
than you will be able to handle it sooner if you quench it to cool it
down.

No oxy-acet torch? Draw a bunch of squiggly lines with a Sharpie marker
in the area you want to anneal. Heat area with a propane torch or other
heat source until the marks disappear.

The heat treatment to get it back to a -T6 condition requires an
accurate heat treating oven, but it will naturally age out to about a
-T3 or -T4 condition in a couple months (IIRC)

Cheers
Trevor Jones