I am installing a small I beam trolley in my work shop that can lift a 1000#
max size of beam is important because of head space so I am looking for
information on length and sizing and capacity of beams

Ed

wrote:
I am installing a small I beam trolley in my work shop that can lift a 1000#
max size of beam is important because of head space so I am looking for
information on length and sizing and capacity of beams

Ed


length of beam and method of supporting said beam are pretty big
factors , a four inch i beanm will carry that load if properly supported

i use a program called beam boy for sizing beams at work , it is
free-ware , just google beam-boy

On Fri, 17 Mar 2006 16:45:26 -0600, WILLIAM HENRY
wrote:

wrote:
I am installing a small I beam trolley in my work shop that can lift a 1000#
max size of beam is important because of head space so I am looking for
information on length and sizing and capacity of beams

Ed


length of beam and method of supporting said beam are pretty big
factors , a four inch i beanm will carry that load if properly supported

i use a program called beam boy for sizing beams at work , it is
free-ware , just google beam-boy

Second that comment. I used beam boy to size the 27ft long beam that holds up
my workshop roof.


Mark Rand
RTFM

How did you determine what an "acceptable" deflection would be? Building
codes?
--
Mr. P.V.'d
formerly Droll Troll
"Mark Rand" wrote in message
...
On Fri, 17 Mar 2006 16:45:26 -0600, WILLIAM HENRY

wrote:

wrote:
I am installing a small I beam trolley in my work shop that can lift a
1000#
max size of beam is important because of head space so I am looking for
information on length and sizing and capacity of beams

Ed


length of beam and method of supporting said beam are pretty big
factors , a four inch i beanm will carry that load if properly supported

i use a program called beam boy for sizing beams at work , it is
free-ware , just google beam-boy

Second that comment. I used beam boy to size the 27ft long beam that holds
up
my workshop roof.


Mark Rand
RTFM

Proctologically Violated©® wrote:
How did you determine what an "acceptable" deflection would be? Building
codes?


i personally use the moment and bending stresses , and a safety
factor of 3 to four , with 36000 psi being a standard for most beams you
dont want to get over 9 to 11 k in the bending and moments , you will
see deflections of less that 1/16 inch for a properly designed beam ,
while anything over 1/8 inch you will see the bending and moment
stresses edgeing up into unacceptable levels

In article ,
says...
Proctologically Violated©® wrote:
How did you determine what an "acceptable" deflection would be? Building
codes?


i personally use the moment and bending stresses , and a safety
factor of 3 to four , with 36000 psi being a standard for most beams you
dont want to get over 9 to 11 k in the bending and moments

The AISC standard uses a factor of safety of 1.67 in most cases, which
results in a working stress of 21.6 ksi for A36 steel.

you will
see deflections of less that 1/16 inch for a properly designed beam ,
while anything over 1/8 inch you will see the bending and moment
stresses edgeing up into unacceptable levels

That's a huge oversimplification. A deflection much greater than 1/8" is
acceptable in a long beam, and a very short beam may fail, probably in
shear, before it deflects 1/16".

Ned Simmons

On Sat, 18 Mar 2006 01:42:20 -0500, "Proctologically Violated©®"
wrote:

How did you determine what an "acceptable" deflection would be? Building
codes?

I Googled for building codes (this is in the UK and there are some fairly
clear and simple national regulations). I also looked for more general-purpose
architectural stuff relating to things like "acceptable beam deflection".

IIRC the number that popped out was a deflection of 1/400th of the span was
acceptable for a roof beam. This worked out at 0.81" for my beam. I designed
for 0.4" when supporting the entire roof load. Effectively this was a 4:1 over
design. I made no separate allowance for snow loading, since the worst snow
loading in this area is two or three inches a couple of times in the last 50
years.

When the walls were built and the roof beam was up, but without the roof on
it, the beam was noticeably springy if you jumped up and down on it. Once the
roof was fixed on to the walls and beam, the whole lot became pretty well
rigid in feel when walking over it. More so than a typical wooden floor in a
house. Roof and walls are both 6" thick SIP's.


Regards
Mark Rand
RTFM

If you are designing a building you use deflection as primary criteria
because what goes in the building needs a stable structure and you want to
avoid floors having a bouncy feel. For cranes you use the moment and
bending stress.as primary and deflection can be greater.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Proctologically Violated©®" wrote in message
...
How did you determine what an "acceptable" deflection would be? Building
codes?
--
Mr. P.V.'d
formerly Droll Troll
"Mark Rand" wrote in message
...
On Fri, 17 Mar 2006 16:45:26 -0600, WILLIAM HENRY

wrote:

wrote:
I am installing a small I beam trolley in my work shop that can lift a
1000#
max size of beam is important because of head space so I am looking for
information on length and sizing and capacity of beams

Ed


length of beam and method of supporting said beam are pretty big
factors , a four inch i beanm will carry that load if properly supported

i use a program called beam boy for sizing beams at work , it is
free-ware , just google beam-boy

Second that comment. I used beam boy to size the 27ft long beam that
holds up
my workshop roof.


Mark Rand
RTFM

In article ,
says...
On Fri, 17 Mar 2006 16:45:26 -0600, WILLIAM HENRY
wrote:

wrote:
I am installing a small I beam trolley in my work shop that can lift a 1000#
max size of beam is important because of head space so I am looking for
information on length and sizing and capacity of beams

Ed


length of beam and method of supporting said beam are pretty big
factors , a four inch i beanm will carry that load if properly supported

i use a program called beam boy for sizing beams at work , it is
free-ware , just google beam-boy

Second that comment. I used beam boy to size the 27ft long beam that holds up
my workshop roof.


I just downloaded Beamboy and played with it a bit and it works very
well, as far as it goes.

But anyone using it needs to understand that while it may yield good
data on stress and deflection, that's not sufficient to insure a safe
design. The most obvious missing factor re the case at hand, a trolley
beam, is lateral stability of the beam. This is usually not an issue if
the beam is built into a structure like a roof or floor system, but is a
real concern with a beam that lacks intermediate lateral bracing.

Just a heads up to warn against getting lulled into a false sense of
security by a neat piece of software.

Ned Simmons

Ned,

You raise a very good point, one that is often overlooked even in
industrial applications.

For unbraced lengths of beam the maximum bending moment must be reduced
so as not to encroach on the buckling resistance of the compression
flange. I had to do a heck of a lot of digging (for a client) to get a
handle on this since textbooks don't address this very well.

I found what I needed in a copy of the Crane Manufacturers Association
of America, Inc. "Specification for Electric Overhead Travelling
Cranes" , spec # 70. (Spec # 74 is more appropriate for manual cranes,
but # 70 is all I got).

It states that the factor of safety of all hoists is 5, BASED ON THE
PUBLISHED AVERAGE ULTIMATE STRENGTH OF THE MATERIAL.

The booklet contains much useful info, and it gives the following limit
on compressive stress for unbraced, single web-beam, crane runways:

Max. compressive stress = 12000 x A / Ld ; with a maximum of .6 x
yield strength

where A = area of the compression flange
L = unsupported / unbraced length of span
d = depth of the beam, in inches

Maximum shear stress = .35 x yield strength

Maximum deflection of beam not to exceed .001125 inches per inch of
span, based on trolley weight and rated load.

Trust this enlightens a little.

Wolfgang

Max. compressive stress = 12000 x A / Ld does not make sense. 12000 x A
is simply 60kpsi steel with a safety factor of 5 tossed in. L times D
for any reasonable beam will be in the 100's eg 10" beam and 60"
supports would be 600.


wrote:

Ned,

You raise a very good point, one that is often overlooked even in
industrial applications.

For unbraced lengths of beam the maximum bending moment must be reduced
so as not to encroach on the buckling resistance of the compression
flange. I had to do a heck of a lot of digging (for a client) to get a
handle on this since textbooks don't address this very well.

I found what I needed in a copy of the Crane Manufacturers Association
of America, Inc. "Specification for Electric Overhead Travelling
Cranes" , spec # 70. (Spec # 74 is more appropriate for manual cranes,
but # 70 is all I got).

It states that the factor of safety of all hoists is 5, BASED ON THE
PUBLISHED AVERAGE ULTIMATE STRENGTH OF THE MATERIAL.

The booklet contains much useful info, and it gives the following limit
on compressive stress for unbraced, single web-beam, crane runways:

Max. compressive stress = 12000 x A / Ld ; with a maximum of .6 x
yield strength

where A = area of the compression flange
L = unsupported / unbraced length of span
d = depth of the beam, in inches

Maximum shear stress = .35 x yield strength

Maximum deflection of beam not to exceed .001125 inches per inch of
span, based on trolley weight and rated load.

Trust this enlightens a little.

Wolfgang

Anyone have any luck w/ this download? The various primary/secondary
download sites (at geocities, prodigy, or Getze's page) ain't workin.
--
Mr. P.V.'d
formerly Droll Troll
" wrote in message
om...
I am installing a small I beam trolley in my work shop that can lift a
1000# max size of beam is important because of head space so I am looking
for information on length and sizing and capacity of beams

Ed

Never mind... seems to be working (finally) from he
http://www.geocities.com/richgetze/
--
Mr. P.V.'d
formerly Droll Troll
"Proctologically Violated©®" wrote in message
...
Anyone have any luck w/ this download? The various primary/secondary
download sites (at geocities, prodigy, or Getze's page) ain't workin.
--
Mr. P.V.'d
formerly Droll Troll
" wrote in message
om...
I am installing a small I beam trolley in my work shop that can lift a
1000# max size of beam is important because of head space so I am looking
for information on length and sizing and capacity of beams

Ed