The image above represents diameter of driver pulley.

To compute for diameter of driver pulley, three essential parameters are needed and these parameters are **Diameter of Driven Pulley (D _{b}), r.p.m. of Driver Pulley (r_{a})** and

**r.p.m. of Driven Pulley (r**

_{b}).The formula for calculating diameter of driver pulley:

D_{a} = ^{(Db x rb}/_{ra}

Where:

D_{a} = Diameter of Driver Pulley

D_{b} = Diameter of Driven Pulley

r_{b} = r.p.m. of Driven Pulley

r_{a} = r.p.m. of Driver Pulley

Let’s solve an example;

Find the diameter of driver pulley when the diameter of driven pulley is 12, the r.p.m of driven pulley is 24 and the r.p.m of driver pulley is 10.

This implies that;

D_{b} = Diameter of Driven Pulley = 12

r_{b} = r.p.m. of Driven Pulley = 24

r_{a} = r.p.m. of Driver Pulley = 10

D_{a} = ^{(Db x rb}/_{ra}

D_{a} = ^{(12 x 24)}/_{10}

D_{a} = ^{288}/_{10}

D_{a} = 28.8

Therefore, the **diameter of driver pulley **is **28.8 m.**

Nickzom Calculator – **The Calculator Encyclopedia** is capable of calculating the diameter of driver pulley.

To get the answer and workings of the diameter of driver pulley using the **Nickzom Calculator – The Calculator Encyclopedia. **First, you need to obtain the app.

You can get this app via any of these means:

**Web** – https://www.nickzom.org/calculator-plus

To get access to the **professional **version via web, you need to **register** and **subscribe **for** NGN 2,000 **per** annum** to have utter access to all functionalities.

You can also try the **demo **version via https://www.nickzom.org/calculator

**Android (Paid)** – https://play.google.com/store/apps/details?id=org.nickzom.nickzomcalculator

**Android (Free)** – https://play.google.com/store/apps/details?id=com.nickzom.nickzomcalculator

**Apple (Paid)** – https://itunes.apple.com/us/app/nickzom-calculator/id1331162702?mt=8

Once, you have obtained the calculator encyclopedia app, proceed to the **Calculator Map, **then click on **Materials and Metallurgical **under **Engineering****.**

Now, Click on **Ball Mill Sizing**** **under **Materials and Metallurgical**

Now, Click on **Pulley Size **under **Ball Mill Sizing**

Now, Click on **Diameter of Driver Pulley**** **under **Pulley Size Calculations**

The screenshot below displays the page or activity to enter your values, to get the answer for the diameter of driver pulley according to the respective parameters which is the **Diameter of Driven Pulley (D _{b}), r.p.m. of Driver Pulley (r_{a})** and

**r.p.m. of Driven Pulley (r**

_{b}).Now, enter the value appropriately and accordingly for the parameter as required by the **Diameter of Driven Pulley (D _{b})** is

**12**

**, r**

**.p.m. of Driver Pulley (r**is

_{a})**24**and

**r.p.m. of Driven Pulley (r**is

_{b})**10**.

Finally, Click on Calculate

As you can see from the screenshot above, **Nickzom Calculator**– The Calculator Encyclopedia solves for the diameter of driver pulley and presents the formula, workings and steps too.