IR type 30 model 253 compressor pulley & age

[bob15]

Last night I brought home an old IR type 30 Model 30 compressor (tank is dated 1944, compressor has a serial of 192540 and a date of 01-61 below that). I read that last 2 digits of the serial number is the manufacture date, does that put this compressor as a pre-WW2, with a possible factory re-build in 1961?

It is supposed to be a 5 hp motor, but was changed to a 2hp, 3 phase motor sometime in its life. The motor pulley was also changed from a 3 groove to a 2 groove. Considering that I need single phase, I figured am going to put a 5 hp baldor motor (L1430T) on it, but I would like to also install the correct motor pulley.

What is the correct pulley diameter? I found one website that showed 5". Is this correct?

 

[Fixnair]

Sheave your motor to turn your compressor @860 RPM. If you are using an 1800 RPM motor you would use a sheave appx one half the diameter of your compressor sheave.
Use the formula, Comp sheave diameter times Comp RPM divided by Motor RPM the arrive at motor sheave dia. In other words- (DIA X 860) divided by motor RPM = motor sheave dia.

What serial number are you referring to. The compressor serial should begin with 30T, rhich is the designator for "air cooled".

Also,that serial number has too many digits for a compressor that old. The receiver may have been mfg. in' 44 but I doubt the compressor is that old.

If it was being driven by A 2 HP motor, two belts would transmit the required horsepower. At 5 HP you would need 3 belts.

 

[G_P]

This will give you your required motor sheave (pulley) size and the belt length you will need.
Its a useful website tool for anything driven by belts.

http://www.blocklayer.com/pulley-belteng.aspx

 

[bob15]

Thanks for the info and the link.

Here is the serial tag: