[Ask] Beam pump Up&Downstroke Speed

[rnds]

Hello everyone,

I need some guidance about the upstroke and downstroke interval settings in beam pumping (not the conventional one, but Hydraulic Pumping Unit).

I want to know about the effect of time difference between upstroke and downstroke
for example: a) upstroke time = 8 second, downstroke time = 4 second
b) upstroke time = 6 second, downstroke time = 6 second



From the example point "a" and "b", my understanding now is:



1. Fast downstroke time in case "a" can make some trouble to the intake of the pump, less fluid that can enter the pump than the pump fluid capacity due to the fast transition between downstroke to upstroke. (it's also affect by the free gas)

2. May cause buckling issues at the fast upstroke time (case "b") but better for rod stress from the constant interval.

3. I am not sure with this one, Impulse load at case "a" for downstroke-to-upstroke is greater than case "b" downstroke-to-upstroke. (this affects the peak rod load and minimun rod load.)

I want to know is the balance interval is the best result and the common practical application in the field with this problem.

Hope for the correction for the point that trying to explain my level of understanding and for your feedback.