- #1
CameronRose
- 12
- 1
Hi folks,
I'm currently working on the design of a triplex plunger pump. I have conducted an investigation into the loading of the pump at maximum operating pressure using an analytical method (free body diagrams) and using rigid body dynamics to validate.
In both analyses the pump has been treated like a slider crank mechanism (except with three sliders 120° apart). My project requires that I use industry standard dimensions for the initial design so I have based the dimensions on the Weir 2500 TWS Destiny frac pump. The pump has a 10'' stroke and 4'' plungers, I have rounded these figures to 250mm and 100mm for the sake of working in metric units. Weir claim in their brochure that the pump can achieve 150MPa output with a flow rate of 170 GPM (12.881*10-3m3s-1) whilst being run from a 2500hp external source. Weir rate their maximum rod load at 273000lbf.
My design has a 250mm stroke, 100mm plunger diameter and I am striving to meet the same output potential as the case study pump. I have calculated maximum torque at 157.63kNm and in turn calculated the power requirement at around 2905hp, the analytical results and computer generated ones match each other. I have not even taken friction into account and my power requirement is considerably higher. My rod load is even 10000lbf lower than their maximum rating.
I'm struggling to see how I can reduce the power requirement of the design, I cannot change the flow rate required so logic would suggest I need to reduce the torque somehow. However, I cannot reduce the stroke of the piston so I cannot reduce the diameter of the crank, I cannot reduce the operating pressure so I cannot reduce the load on each piston. There is a gearbox between the input and pump however, with the exception of any parasitic losses this should not affect the power requirement, it seems more logical to attempt to reduce torque at the crank.
My normal area of focus isn't mechanical so I'm not really sure how to proceed here in order to reduce the maximum net torque. If anyone has any suggestions on things I could look into please help!
Cameron
I'm currently working on the design of a triplex plunger pump. I have conducted an investigation into the loading of the pump at maximum operating pressure using an analytical method (free body diagrams) and using rigid body dynamics to validate.
In both analyses the pump has been treated like a slider crank mechanism (except with three sliders 120° apart). My project requires that I use industry standard dimensions for the initial design so I have based the dimensions on the Weir 2500 TWS Destiny frac pump. The pump has a 10'' stroke and 4'' plungers, I have rounded these figures to 250mm and 100mm for the sake of working in metric units. Weir claim in their brochure that the pump can achieve 150MPa output with a flow rate of 170 GPM (12.881*10-3m3s-1) whilst being run from a 2500hp external source. Weir rate their maximum rod load at 273000lbf.
My design has a 250mm stroke, 100mm plunger diameter and I am striving to meet the same output potential as the case study pump. I have calculated maximum torque at 157.63kNm and in turn calculated the power requirement at around 2905hp, the analytical results and computer generated ones match each other. I have not even taken friction into account and my power requirement is considerably higher. My rod load is even 10000lbf lower than their maximum rating.
I'm struggling to see how I can reduce the power requirement of the design, I cannot change the flow rate required so logic would suggest I need to reduce the torque somehow. However, I cannot reduce the stroke of the piston so I cannot reduce the diameter of the crank, I cannot reduce the operating pressure so I cannot reduce the load on each piston. There is a gearbox between the input and pump however, with the exception of any parasitic losses this should not affect the power requirement, it seems more logical to attempt to reduce torque at the crank.
My normal area of focus isn't mechanical so I'm not really sure how to proceed here in order to reduce the maximum net torque. If anyone has any suggestions on things I could look into please help!
Cameron