### Re: Conveyor Gd2 Value

Dear Deenar Apta,

GD^2 is the ancient way to describe the moment of inertia in kgf.m^2.

Nowadays, the moment of inertia is given as I = integral {distance^2 * d(mass)] in kg.m^2

It is the resistance against rotational changes, given by Torque = I * d(omega)/d(t)

Linear equivalent is Force = mass * d(velocity)/d(t)

This value plays a role in drives during acceleration and deceleration and is therefore a valid factor.

This value even influences the settings and characteristics of the protection devices of the electric drive motors and power supply grid.

The mass of the chain and possible load can be assumed on the pitch diameter of the drive sprocket.

The friction can be taken as retarding force, acting as a retarding torque on the sprocket pitch diameter.

Rpm converters s.a. gearboxes and belt drives convert the I with a factor of the gear ratio to the square.

Take a deep breath and start calculating with Newton laws

It takes a well experienced engineer to handle these issues.

Take good care

Teus ■

Teus

### Re: Conveyor Gd2 Value

designer,

Do you really think that an inexperienced engineer can perform such a calculation just because it is in metric units???

Yesterday, I could not even spell the word engineer

and now I am one.

Have a nice day

Teus ■

Teus

### Re: Conveyor Gd2 Value

Well I could, and in Imperial, and without a degree!!! ■

### Re: Conveyor Gd2 Value

In north America, the inertia reference is in mass (W) x radius of gyration (r)^2 units. Normally, this is expressed in kg-m^2, the same reference units as GD^2. One is 4 x times the other. This becomes a little confusing when the european motor suppliers quote in GD^2 units, but only state the units. You multiply GD^2 x 4 to obtain Wr^2 units?

So, giving a Inertia value in kg-m^2 is not sufficient. Is it radius of gyration or diameter of gyration? ■

### Strength In Unit..Sity

Dear Teus,

It should read.

"And now I are one."■

### Re: Conveyor Gd2 Value

@ designer

and without experience ?

@ nordell

There is only one inertia value in kg.m2.

As you said yourself: mass (W) x radius of gyration (r)^2

There is only one RADIUS OF GIRATION.

@ louispanjang

“you is a better engineer than I”

Have a nice day

Teus ■

Teus

### Re: Conveyor Gd2 Value

Who sez engineres kant spel? ■

Gary Blenkhorn

President - Bulk Handlng Technology Inc.

Email: **garyblenkhorn@gmail.com
Linkedin Profile: http://www.linkedin.com/in/gary-blenkhorn-6286954b**

Offering Conveyor Design Services, Conveyor Transfer Design Services and SolidWorks Design Services for equipment layouts.

### Re: Conveyor Gd2 Value

I thought the inability to spell and use correct grammar was the hallmark of an engineer ■

## Conveyor GD2 Value

Can anybody help me with method / procedure to calculate GD2 value of chain conveyor. I wonder whether it is a valid factor for chain conveyor?

Deenar Apte ■