Inquiry Regarding Flushing Plan for VS4 or VS5 Type API Pumps

Can you suggest which flushing plan to suggest also.I am not able to visualise how can we get plan 53 flushing plan connection in VS4 or VS5 type pumps.can you help

You would use packing in a pump, only if you can handle the slight amount of leakage necessary to lubricate the packing. In a dual mechanical seal, you will have a barrier fluid "in" port and a barrier fluid "out" port. In a dual seal, the outer seal has a pumping ring to circulate the barrier fluid. In plan 53 A & B the barrier "in and barrier "out" ports are piped to a pressurized reservoir and the barrier fluid is circulated between the seal and reservoir, the reservoir will have some method of cooling the barrier fluid. Also, the barrier fuild has to be compatible with the product being pumped.