[janak1235]

My phone see in network pin driv how to convert disk drive see in my comuter

[DaFoxGrey]

My phone see in network pin driv how to convert disk drive see in my comuter

There are a few reasons and fixes:

You will need to use a USB cable that is for data and charge, not charge only.
You will need BlackBerry Device Manager drivers installed on the computer, these are installed as part of BlackBerry Link or BlackBerry Desktop Software. If the computer has a Plug-n-Play OS, it should detect the BlackBerry and attempt to download the need drivers.
Depending on your BlackBerry device, you can enable Mass Storage Mode via Settings for storage.
Some model legacy BlackBerry devices, if they were refurbished, may have had the ROM altered that introduced a bug where the device could no longer be seen by the computer unless BlackBerry Desktop Software was running, see:
KB19717-The BlackBerry smartphone is not detected as a USB Mass Storage Device when connected to a computer