Parker K220LS Relief Valve 2

[HydroBuff]

Hi everybody,

I have a couple of questions on a Parker K220LS valve using an ASC mid inlet. (part number 22000667)
Would you know what the application uses would be for part number 9120092290? Can I use that in an ASC mid-inlet if I don’t have any AS compensators?

Also, I would like to know if using PLS relief (part number 9120092269) will limit my max system pressure to a certain point lower than what PLM would.

Thank you.

 

[FluidPowerUser]

Perhaps start a thread asking how to move a thread to a different location or forum?

 

[Compositepro]

Use the red flag (report) to communicate with site management.

 

[HydroBuff]

Thanks Compositepro! I will try that.

 

[HydroBuff]

Hi everybody,

I thought I would give an update here, in case anyone has ever heard of a similar situation; for some reason adjusting the PLM relief screw does not even lower the LS pressure.
Am I correct in my understanding that it should? Why would it continue to build pressure with the adjustment as low as possible?
I replaced the PLM relief valve in case that was faulty, but no change whatsoever.

 

[FluidPowerUser]

Hello...

Let's get some things clear. I know you have said that you are using the ASC inlet, but can you confirm that you are not using any AS compensators at all?

Also, how many sections are you using and are any of them L90LS type?

We need to confirm the setup you have as the PLM+PLS arrangement is designed to work with the AS type compensator.

Thanks!!!

 

[HydroBuff]

Absolutely! I apologize for not providing all the details immediately. Let me know if I miss any here.

We are using an ASC mid-inlet which is designed for AS style compensators. We are not using any AS style compensators, but my understanding was is that it should work with standard compensators. Please correct me if I am wrong here.
On the K220 side I have 2 sections, one with feed reducers and one with no feed reducers or work port reliefs. This section is where I need to be able to build at least 4000 psi.
On the L90LS side of the inlet I have 6 sections, all with feed reducers and port reliefs so that I can lower the pressure to 2000 psi on those sections.
I am using a variable pump for this setup.

Let me know if there are any other details I could share that would be pertinent to the question.

Thank you!

 

[HydroBuff]

FluidPower, you did get me thinking,

Do you think that I would be required to have at least one AS type compensator valve section?

Thanks!

 

[FluidPowerUser]

Looking at the data from Parker, which isn't very clear, it says this.

If you have a variable load sensing pump and are using LS type compensators, you need to use the LS2 or LS2C inlet. According to the above.

Using the ASC inlet with LS compensators can mess up the load sense copy valve and the pre compensators on each section.

Also, can you confirm which line is going back to the pump compensator? PL or LS?

On the ASC inlet, the internal resolved loas sense signal from the sections is on the PL line and it also connect to the PLS and PLM valves to control the max pressure in the system and also the flow.

The load sense copy valve fills the LS galleries from the pump pressure line and it controls the pre compensators. The pressure in the LS line is controlled by the PL gallery pressure balanced with the LS pressure. The LS pressure and the resolved load pressure (LSP) get fed to each side of the pre compensator too, for flow sharing.

From what I can, using an ASC inlet with only LS compensators will not let the compensators work properly. The LS signal cannot get to the compensator to keep it open, so it will try to close the flow off. Looking at the schematic on the Parker data sheet, I'm surprised it's working at all.

Have a look at pages 8 and 9 on the Parker data sheet and see if you can see what I mean. I can elaborate if needs be.

Again, it seems unduly complicated and Parker offer no explanation of what the load sense copy, PL and LS and LSP functions add.

 

[HydroBuff]

That's also the conclusion I have come to, my mistake for not properly understanding the manual.
I had understood it to say that the LS comps work just fine with the ASC and since that is the part our company had in stock for another application, that's what I used.

As far as to which port my load sense line was hooked up to, I had tried both as you will remember from above and got different results. Using the LS port I could build 4000 psi. but it would leak down too quickly. Using the PL port it would max out at 3200 psi.

I think I have learned a lot about these valve, thanks to you FluidPower. I highly appreciate your contribution here.
Hopefully I can help someone else after I have your years of experience!

 

[FluidPowerUser]

No problem at all. Happy to help.

Come back if you need more.

Good luck!!!

 

[HydroBuff]

OK, back I come.
I tried to install a KAS type compensator in my valve, all to no avail.
A Parker engineer finally responded to my request and informed me that it should actually be just fine to have all standard LS compensators with an AS type inlet.

I guess I am back to the drawing board.
Does anyone here know if Parker offers any type of traing or tools for anyone in the valve engineering? Such as simulation software or a configurator?

Best Regards,

 

[FluidPowerUser]

https://parkersupport.parker.com/us...igurator-search?brd=part-configuration&app=hs

It's not very good.

I have also looked in the online catalogues for Automation Studio, which is hydraulic simulation software. However, the Parker mobile valves such as the K220LS are not there.

It's easy to see why Parker have gone backwards in terms of global market share in fluid power.

 

[HydroBuff]

HI @FluidPowerUser,

Apparently, my other valve had a slightly different configuration and therefore it could build higher pressures with the same pump compensator setting.
That fooled me into believing that the pump setting wasn’t the problem. I can now correctly adjust and change pressure settings since I raised the pump compensator.

Thanks so much for your patience with me here without knowing all the details of the system but being willing to try anyway.

 

[FluidPowerUser]

No problem.

I’m glad you found the solution.

All the best