Motor Kw And Capacity

A customer once asked . with the same pump can I increase the flow with 10 hp instead of 5 hp now ?

Definitely not , but this is quite a common question as people still think bigger motor give more pressure or
capacity
The flow is determined by the pump size at given speed .Increasing the speed will increase the capacity and will required higher motor Kw .Check pump performance curve and determine what is the new duty needed
Also note the maximum speed of that pump

Air Operated Pumps

Dear Basir


Air Operated Pumps certainly have its advantages , and one is dry running capability when transferring chemicals from drum unattended . It limitations are air supply requirement , for standard pumps the maximum is 8.6 bar
You need to make careful selection , ensure material of pump is compatible to your chemical
As for occasional check valve failure , maybe due to the dirt or solids stuck in between the ballcheck
Install Strainer for the purpose

Level Control can be installed by means of float switch and solenoid valve to shut off
The shut off valve can pneumatically or electrically controlled

Pressure -- Pump Pressure or System Pressure

A Senior Engineer asked me sometime ago ,why the pressure gauge only show 3 bar but you said your pump can go maximum 10 Bar ?
The gear pump is was for lubricating bearings with an open end outlet ,check and found the flow is in order .I tried explaining to him the system pressure is 3 bar ,therefore the working pressure is 3 bar unless the discharge line is blocked or there is obstruction . A shut off test was done ,and the pressure gauge registered 10 bar easily .A lot of explaining was done but he did not want to listen as he feel that he knows better . I just took back my pump

After that .I was told he get another 2 or 3 pumps from other suppliers and encountered the same problem .This is one of the common problems we always have to deal with
It is a simple issue ,unless people listen

Pump Selection by Software

There is an increasing use of software to size and select pumps , but user
should verify the pump selected against the operating condition such as media characteristic
An example , a Lobe pump was selected and designed to run at approx 750 rpm for liquid detergent .The pump can perform, but the product is shear sensitive and it is going to create a lot of bubbles at the storage tank

Therefore . the user or engineer should take this into consideration and determine what is the maximum operating speed for the media.Experience plays a part when come to selection of pumps