Excise duty calculation

The calculation is correct but If you are registered with central excise then you can issue the taxable invoice and buyer can take the cenvat credit on capital goods. 

Dear Kumar

Your question is not clear. Are you a dealer of the tool you have purchased or you had purchased it for your own consumption?

Moreover Excise duty is leviable only on manufacture. As you have not done any manufacturing on the tool hence you are not liable to pay any excise duty. You can simply pass on the the CENVAT credit to the vendor. For this you will have to get registered under Central Excise.