ASIT859
Mechanical
- Aug 24, 2017
- 27
Hello everyone,
I’m looking for help in finding what I can best describe as a pressure compensated flow regulator or pressure compensated flow control valve for compressed air. I know that these valves are readily available for fluid power applications, but I cannot seem to find what I need for use with compressed air. To avoid an “XY problem,” my application is described below, just in case someone has a recommendation for a different approach.
I’m trying to run an air motor at a near constant speed. I don’t need to maintain a precise speed, but I’m looking to minimize the change in speed based on the load on the motor. I have a pressure regulated compressed air supply and a variable load on the motor. By controlling the air consumption of the motor, I believe I can control the motor speed.
Below is a simple schematic of the arrangement. The air motor is driving a positive displacement transfer pump. The load on the pump will vary depending on the operating state of the fluid system and I’m trying to keep the flow rate relatively steady. The schematic below is shown two ways – one option uses a simple symbol for a pressure compensated flow control valve and the other is more in-depth. I can’t seem to find either valve using simple searching. Below is an article related to pressure compensated flow control that provides some background on the concept, but is focused on a fluid power application.
I just simply cannot find a pressure compensated flow control valve for air and I also cannot seem to find the external pilot valve depicted in the second example.
Thank you.
[edit] I forgot to mention that in order to help provide additional context, I'm looking for a control valve that can limit the flow rate to somewhere around 20 to 30 SCFM with a pressure drop no greater than 40-psid at such a flow. I can easily select a fixed orifice (for the second example schematic) that gives me the approximate flow rate @ such a pressure drop, but then I'm stuck trying to find the pilot operated/controlled valve.
The Effects of Pressure Compensated Components on Control Systems (Fluid Power Journal)
I’m looking for help in finding what I can best describe as a pressure compensated flow regulator or pressure compensated flow control valve for compressed air. I know that these valves are readily available for fluid power applications, but I cannot seem to find what I need for use with compressed air. To avoid an “XY problem,” my application is described below, just in case someone has a recommendation for a different approach.
I’m trying to run an air motor at a near constant speed. I don’t need to maintain a precise speed, but I’m looking to minimize the change in speed based on the load on the motor. I have a pressure regulated compressed air supply and a variable load on the motor. By controlling the air consumption of the motor, I believe I can control the motor speed.
Below is a simple schematic of the arrangement. The air motor is driving a positive displacement transfer pump. The load on the pump will vary depending on the operating state of the fluid system and I’m trying to keep the flow rate relatively steady. The schematic below is shown two ways – one option uses a simple symbol for a pressure compensated flow control valve and the other is more in-depth. I can’t seem to find either valve using simple searching. Below is an article related to pressure compensated flow control that provides some background on the concept, but is focused on a fluid power application.
I just simply cannot find a pressure compensated flow control valve for air and I also cannot seem to find the external pilot valve depicted in the second example.
Thank you.
[edit] I forgot to mention that in order to help provide additional context, I'm looking for a control valve that can limit the flow rate to somewhere around 20 to 30 SCFM with a pressure drop no greater than 40-psid at such a flow. I can easily select a fixed orifice (for the second example schematic) that gives me the approximate flow rate @ such a pressure drop, but then I'm stuck trying to find the pilot operated/controlled valve.
The Effects of Pressure Compensated Components on Control Systems (Fluid Power Journal)