Parallel offsets and kicks

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liquidtite

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Is their a formula for figuring out how much you have to add to each offset to maintain your spacing in between the same with multiple conduits on a rack

And is the formula the same if you have multiple kicks on a rack
 
I would really appreciate if any one knows how to find out how much you need to add to each bend when you have multiple 90' kicks on a rack

thanks you for your time ;)
 
I don't know any formula for it although I am sure it exists.

I just go for it on some scrap to figure it out if I have doubts.
 
iwire said:
I don't know any formula for it although I am sure it exists.

I just go for it on some scrap to figure it out if I have doubts.
Click to expand...

I was thinking of bending the first 90 with a 45 ' kick on it .then outlining it on the floor and moving it up to the outline to get my proper space between conduits then see how much it moved up from the outline .

im hoping this method will be accurate I'm going to try it out

thanks got any input you guys are the best
 
I usually bend two pipes, lay side by side on the floor and move them around till they look good and then figure out how much extra each one would need from that.

I don't feel like I am explaining it to well but it has worked for me.
 
To make parallel runs, advance/retard each bend by
tan(a/2)*s​
where "a" is the bend angle and "s" is spacing (centerline to centerline).

This assumes the stub end is at a right angle to the preceding run (aligned couplings). Adjust accordingly if not.
 
Smart $ said:
To make parallel runs, advance/retard each bend by
tan(a/2)*s​
where "a" is the bend angle and "s" is spacing (centerline to centerline).

This assumes the stub end is at a right angle to the preceding run (aligned couplings). Adjust accordingly if not.[/

so is this a formula for multiple 90s on rack with no no kicks .
If so i just add the distance Inbetween the conduits than add the over all dimension of the conduit to each 90
Click to expand...
 
liquidtite said:
so is this a formula for multiple 90s on rack with no no kicks .
If so i just add the distance Inbetween the conduits than add the over all dimension of the conduit to each 90
Click to expand...
Distance between conduit plus OD (outside diameter) of one is equal to the center-to-center spacing where conduits are the same OD. Not the same when conduits are different OD's.

For 90's it's simple.... just add/subtract the spacing amount for each successive-run's bend mark (where conduits are same OD).
 
Last edited:
Oo so if you had 90,that were on a right angle kicking up of down,

in my situation. I have 9 3/4 conduit on a rack stubbing down into pullbox .

the 90,s have a 45' kick in them to inter pullbox .

The he kick is approximately 30 "
 
liquidtite said:
Oo so if you had 90,that were on a right angle kicking up of down,

in my situation. I have 9 3/4 conduit on a rack stubbing down into pullbox .

the 90,s have a 45' kick in them to inter pullbox .

The he kick is approximately 30 "
Click to expand...
You need to be very descriptive when you start compounding the number of bends in a text-based discussion without the benefit of viewing the project. As you know, conduit runs are 3-dimensional, while so far your description is only 2-dimensional... the latter being fine if all the bends are in the same plane... but if not you have to elaborate... (or provide pictures???)

Is rack horizontal (e.g. on trapeze) or vertical (e.g. on wall), and direction (east-west, north-south)?

Pullbox placement/orientation (east-west, north-south; on wall, on angled wall, on machine, etc...), dimensional offsets with respect to pipe rack, etc.

Attached depiction is just one possible scenario....
 

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Sorry I don't know how to rotate the pic The 90,s stub down into a pullbox that is at a lower level than the of the rack .

The 90,s are kicked with 45 '
the kick is approximately 30" I can get exact kick tomarow .
Center to center is 1 3/4 "
Spacing side to side is 3/4 "


I bent these conduits by just guessing with the numbers to add each time and ended up
wasting a few sticks and taking more time than Id like to .

Im going to build a back to back rack underneath the existing rack and have anouther set of conduits enter in front of the ones I just did in pullbox .


This time idd liked to be better prepared . If I'm leaving anything out let me know I really appreciate your time and knowledge
 
That's deff why I was having so much trouble .
Next time I'll deff off set them and then 90 .

i was able to get the spacing pretty close .
Dosnt look bad but to much trouble .
 
liquidtite said:
Sorry I don't know how to rotate the pic The 90,s stub down into a pullbox that is at a lower level than the of the rack .

The 90,s are kicked with 45 '
the kick is approximately 30" I can get exact kick tomarow .
Center to center is 1 3/4 "
Spacing side to side is 3/4 "


I bent these conduits by just guessing with the numbers to add each time and ended up
wasting a few sticks and taking more time than Id like to .

Im going to build a back to back rack underneath the existing rack and have anouther set of conduits enter in front of the ones I just did in pullbox .


This time idd liked to be better prepared . If I'm leaving anything out let me know I really appreciate your time and knowledge
Click to expand...
If the rack side is 1-3/4" spacing, the spacing between the 45's and rolled 90's drops to about 1-1/4"

Doing that configuration, each 45 from the rack will be at the same distance from aligned couplings, same distance after the bend to the 90, then spacing is restored to 1-3/4" going into the box.
 
Smart $ said:
To make parallel runs, advance/retard each bend by
tan(a/2)*s​
where "a" is the bend angle and "s" is spacing (centerline to centerline).

This assumes the stub end is at a right angle to the preceding run (aligned couplings). Adjust accordingly if not.
Click to expand...

I found a simple method that gives results that equal the tangent method.

Simply convert the offset angle to a decimal value (ie 45°=.45) then multiply that by the center to center spacing. This is far easier to remember and can even be done without a calculator. The accuracy is within 1/16", which is more than adequate.
 
rlundsrud said:
I found a simple method that gives results that equal the tangent method.

Simply convert the offset angle to a decimal value (ie 45°=.45) then multiply that by the center to center spacing. This is far easier to remember and can even be done without a calculator. The accuracy is within 1/16", which is more than adequate.
Click to expand...
It's a decent approximation as can be evidenced at the far end: multiplier is 1.0 for a 90, while your method gives a 0.9.

After the fact, we judge spacing by eye anyway.
 
rlundsrud said:
I found a simple method that gives results that equal the tangent method.

Simply convert the offset angle to a decimal value (ie 45°=.45) then multiply that by the center to center spacing. This is far easier to remember and can even be done without a calculator. The accuracy is within 1/16", which is more than adequate.
Click to expand...

. So if my kick is 45' and spacing is 1" 3/4 center to center

I did .45 x 1.75 equals .7875 ?
 
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