Before you made the decision, consult with Process Engineers if the equipment will be commisioned with water - it is extremely relevant especially when the process fluid density is much lower that the water
Please understand something - API 610 IS NOT A SET OF MANDATORY REQUIREMENTS - any provision can be negociated /changed/deleted as per Client's specific requirements
With regard to the open impeller - technically API 610 does not refer to pumps equipped with open impellers - however, I did once...
I subscribe to the answer you have received from Pumpsonly - the combination shall work fine - the seal faces do not get process fluid at all because the barrier fluid has a higher pressure , therefore the fluid passes the seal faces in the opposite direction (against) to plan 11 flow
Even the permanent magnets do have a slip - with every slight change in pressure or conditions of the pumped fluid or with every slight speed change of the motor.
To prove this it will be probably be enough to monitor the temperature of the pump in the magnetic coupling area because the slippage...
It is in my opinion an unfortunate decision - this pump will experience temperature shocks at every change of duty - apart from the case itself and all the wet components - how will the bearing and coupling alignment cope with this ? The seal faces ? How will the seal plan switch over be...
As a rule of thumb (also used by few reputable petrochem companies ) , up to 15 kW installed power it is considered more efficient to have a permanent recirculation line fitted with an orifice. ( in which case the recirculation constant flow needs to be added to the required process duty )
As already explained, Sundyne vertical turbine pump is a niche product which as far as I know does not have a real competition. For a similar set of duties, most other manufacturers will recommend a multistage pump - I was once offerred a 14 stage pump to 'replace' a Sundyne ...it is really no...
If my understanding is correct - you wish to see the maximum electrical power consummed by the pump - in this case you've got your answer from quark - moving the pump duty point at the right side of the curve translate into maximum electrical power needed
CAREFUL - that also translate into more...
In order to get some protection to the existing pumps and to asess the nature and magnitude of the 'dirt' problem, use a dual filter system with a switch-over function placed in the suction pipe of the pumps.
If the size of the particles found on these filters xceeds tolerable sizes and/or...
The curve given by the Manufacturer is valid for all the listed impellers. Use the relevant data at the flow provided by the pump with the new impeller.
If indeed you are in no position to query why a 6 "
discharge piping is used on a 2 " pump - as rightly Artisi has pointed out - there is no economical uncertainty about the valve -> 2 " is vastly cheaper than 6 " valve and there is no engineering advantage to go for the bigger valve in this...
Other issues with magdrives :
1. They cannot be implemented for dirty fluids due to the hydrobearings using the pumped fluid as lubricant.
2. They shall not be used for variable duty points - the hydrobearings are designed for a certain flow at a certain pressure - any change and the life...
