Bleed bushing mechanical seal

[martinpump]

Hi All,

Can some one, explain me in details what is this bleed bushing mechanical seal generally used in vertical pumps.
If possible let me have any link which gives further details.

Also, i would like to understand vertical pumps, suction lift calculations.
Any guide book which explain calculations of pumps hydraulics.

Thanks
Martin

 

[1gibson]

Otherwise know as a throttle bushing, and/or seal chamber bearing?

The bushing has close clearance to the shaft which breaks down pressure, and an orificed plan 13 (line to suction) above it, in order to create a lower pressure environment for the mechanical seal.

Google McNally institute, its a good "little bit of everything" pump site.