belt driven fan alignment 1

[javan210]

Dear freiends,
I am recently involved in a project to install some air cooled exchanger (Gas Cooler) Fans.
The fans are driven by timing belts throught 2 timing pulley, I am seeking for a procedure or manual for installation and alignment of the system.
Motor and Fan shafts are vertical and parallel and pulleys are fixed by taper bushings.
Thank you

 

[waross]

Experience is the biggest factor. Other than that, verify perpendicular shafts with a machinists level. Then check that the pulleys are level with the level. Check with the level in the same location and rotate the shaft. Check ever 15 or 20 degrees. Use a string and or a straight edge for pulley position alignment.
Use lots of experience.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[catserveng]

As Bill said, experience is the best tool, here is a couple of links,

http://www.lubsys.com/knowledge/knw_align05.htm

http://www.vibralign.com/belt-alignment.html?gclid=CMruyYzk16ACFRdaiAodDjmcBg

I am a big fan of using a laser alignment system for belt drives when possible. When CAT engines started going into large tub grinders we had a large number of problems, the folks at Vibralign were a big help and their tooling helped us in a number of applications. I've also used the tooling from SKF, and their tech support people are very helpful.

Mike L.

 

[amptramp]

Synchronous (Timing) belts require proper "engineering" for a successful installation. For example, some belt manufacturer's offerings such as the Gates PowerGrip GT2 have proprietary tooth profiles requiring matched pulleys. The Gates website has "design manuals" available for download. The design manuals discuss belt alignment. Coincidentally, there is also a design manual specifically for heat exchanger applications.

As stated previously, there is no substitute for experience, especially with synchronous belts.

FYI, I do not "sell" Gates products. I chose Gates for illustration purposes only.

 

[waross]

When aligning with a straight edge, I have four points of contact. My last check with straight edge alignment is to pinch a $5 bill in each contact point in turn and pull it to feel the drag.
Ever watch a group spend days aligning a 3 HP motor only to have it go out of alignment every time it is run?? If you don't make your first step, check that the pulleys are square on the shafts, you will some day experience some frustration.
How often do you see this step emphasized in textbook alignment procedures? My rant is that some of the people writing the procedures should stop just cribbing from another textbook or making it up as they go and get out in the field and get dirty for a few years. Experience. [Rant off]
You may replace my straight edge or string with a laser, but don't take away my level. I need it to check that the pulley is square on the shaft. Experience.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Tmoose]

Are the motors on adjustable bases? Some of those are miserable at keeping things aligned during belt tensioning/adjustment, or so flexible that under power running alignment is completely different than the static alignment.

Dan T

 

[javan210]

Dear TMOOSE,
The motors are mounted in fix bases.
Thank You.