Hydraulic circuit design software 9

[frans]

Does anybody in the forum have experience with hydraulic circuit design software. I would like to simulate operating conditions in complex circuits and get results such as flow losses, pressures and temperatures.

 

[CanuckMiner]

I suggest having a look at Automation Studio. I haven't tried it, but I've come across their literature, and it looks impressive. It might do what you want.

http://www.automationstudio.com/

Cheers,
CanuckMiner

 

[kcj]

I have been looking also.

Last time we looked, Automation Studio did great animation, schematics, training and color coding,motions, flows and steady state pressure drops, but NOT dynamic analysis of accel, decel, shock, etc.
That's what I really was looking for, so have not n\yet found something. There are several highly analytical dynamic programs, but beyond my level.

kcj

 

[budt]

Try this site for Easy5 software. If you have deep pockets it is supposed to tell all about everything just like a running circuit.

http://www.mscsoftware.com/products/products_detail.cfm?PI=414

I have not used it so I cannot say first hand how good it is.

Delta Computer Systems does some modelling of motion control circuits but I don't think it is a for sale program. You can check with Peter Nachtway at this site.

http://www.deltacompsys.com/

Bud Trinkel CFPE
HYDRA-PNEU CONSULTING, INC.
fluidpower1 @ hotmail.com

http://www.fluidpower1.us

 

[frans]

I have emailed automation studio twice in the past week requesting prices but not received a reply yet. Any idea on pricing of Easy5?

 

[budt]

When I first heard about it 10 years ago it seems the price was over $8,000.00. That was the reason for the reference to deep pockets. Even Automation Studio is over $4.000.00 the best I remember. Automation Studio doesn't claim to be true simulation but does have some variables like setting pressure and flow controls.

Here is another place to look that has a whole list of Simulation software.

http://fluid.power.net/fpn/docs/software.php3

Bud Trinkel CFPE
HYDRA-PNEU CONSULTING, INC.
fluidpower1 @ hotmail.com

http://www.fluidpower1.us

 

[kcj]

Easy5 was part of Boeing at one time. It was $$$, but also had optional mechanical, electrical, heat transfer, etc. ec. modules that would do very valuable dynamic siimulations.
k

 

[frans]

I have an online demo with Automation Studio coming up. Will keep you all posted.

 

[danhelgerson]

I received a quote from Automation Studio about a year ago. The basic professional program was $1,900. The Fluid Power package was $3,440. They would like the customers to also come for training. You probably already have this...

http://www.automationstudio.com/

Dan Helgerson CFPS, AFPI, AJPP

http://www.cfpsos.com

 

[EdDanzer]

Mathworks has their Matlab and Simulink products that will do simulations similar to Easy5.

http://www.mathworks.com/products/product_listing/index.html

Some what spendy though.

 

[PNachtwey]

"Delta Computer Systems does some modelling of motion control circuits but I don't think it is a for sale program."

I do simulations for hydraulic servo systems and system integrators only. What I have is not a product and not for sale. However, we are looking into making a simulator for hydraulic servo systems available on the web. We have found that too many people can not design hydraulic servo systems correctly. It is no wonder. There aren't any simple formulas for cylinder sizing. The VCCM and natural frequency methods are incomplete and can lead to incorrect answers. The only good way to do cylinder sizing is to use a simulator. The down side is they cost money or require solving a system of differential equations.

 

[frans]

Actually I do not think there are too many people who can design a proper hydraulic circuit at all. I have up to now used so called hydraulic specialists working for the big hydraulics suppliers to do the hydraulics for my designs and boy more often tham not I have problems, ranging from overheating to functionality issues. It is as if these guys do not spend enough time thinking through all the potential issues - they are too keen to off-load components. The support afterwards is appalling. I have since realised that general knowledge is not enough and I need to be my own hydraulics specialist. A lot of what I do does not allow the luxury of fixing easily afterwards, so simulating it up front would be ideal.

 

[budt]

frans wrote;

"Actually I do not think there are too many people who can design a proper hydraulic circuit at all."

You are not alone in your experiences. It is probably a lot more to do with Not knowing what is available, what causes heating, what is the best component that I sell, etc. than "Not thinking it through." If you decide to get the knowledge to design your own circuits you will be one of a rare breed in the industrial or mobile world of Fluid Power users.

Training in Fluid Power circuit design comes from manufacturers schools and is quick time at best. From that point on it is the College of Hard Knocks and OJT. Been there and done that.

Until industry decides they need trained, knowledgeable persons in house that have Fluid Power as their primary responsibility Fluid Power will stay the way it is. Anytime another way to perform the work normally handled by Fluid Power that way will be first choice. Electrical is always waiting in the wings to take over and they have the knowledge to do it. Lately I am seeing more jobs go to electrical power due to their constant upgrading and doing things that were unheard of even 10 years back.


Bud Trinkel CFPE
HYDRA-PNEU CONSULTING, INC.
fluidpower1 @ hotmail.com

http://www.fluidpower1.us

 

[frans]

I fully agree Bud. I actually try to use electrical whenever I can, but that does also tend to bind you to a few individuals who were involved with the design and programming and essentially the similar level of expertise needed. I used to argue that since I am not doing hydraulics every single day I am better off using someone living off the stuff - thinking they may know what is available and the individual characteristics of say a particular valve. I have done the training courses but as you say they are basic. The other day I asked so called experts at a training course to explain to me in clear terms where you would use what type of pump, gear vs vane etc - they do not know. Simple as that.

School of hard knocks I tell you - through poor design on my equipment I am learning fast! It does not come cheap though.

 

[EdDanzer]

Very few collages offer hydraulic training so finding someone with formal training is difficult. My school of hard knocks has taught me to be wary of people in any industry. Having a good basic knowledge of any discipline you need to integrate into a product will cut your education costs. Reading trade publications, belonging to trade associations and getting quotes from several vendors can help define the direction to go with a project. I think there as many poorly qualified electronic people as fluid power people.
Unless you are doing very complex designs, modeling software can be overkill. Hydraulics is not any more complicated, than electrical, so a few good reference books can go a long way to checking quoted designs.
A rule of thumb that I tell people is there is no free lunch with hydraulics. Each motion function, and budget must be defined completely before choosing a pump and valve type. The greater the pressure and flow difference between functions the more difficult the problem.

 

[PNachtwey]

[tangent]
As far as I know the only college or university that teaches hydraulic is MSOE and Purdue.

Reading trade journals is not enough to learn the finer points. I know because I have written several articles for H&P and the articles must be written to be more of a teaser. One can't go into any topic too deeply with a 800 word limit and a minimum of formulas and examples.

I agree with EdDanzer's point about the number of unqualified electrical people. I see electric servo designs that are sized in correctly so that the output from the controller saturates at 10 volts just like I see the same for hydraulic designs.
[/tangent]

I don't agree that hydraulics is not anymore complicated than electical. One can find nice simple equations for resistors, inductors and capacitors. Transistors and op-amps can provide gain that is very linear. One can express the response many analog electrical ciruit using Laplace transforms. Finally, I can buy precision parts so an electrical design will work as planned.

Hydraulics is non-linear. Flow through a orifice or valve requires a square root function. Hydraulic specifications are very loose. One valve may be 10% different from another with the same part number. All of these factors makes hydraulic design harder and writing the simulators much more difficult and therefore more expensive. It is hard to even find proper specifications that a simulator can use. Too many assumptions must be made.

 

[EdDanzer]

PNachtwey,
Your point about non-linearity is correct. I was making a general statement about simple applications either electrical or hydraulic. My experience with electric servo drives has never shown great linearity between motors and drives. Replacing either part usually requires retuning the system for stability.
I will suggest that if a drive system requires very precise control and low power electric drives are typically a better choice, partially because of closer tolerance components. For higher power drives hydraulics becomes the best choice up to about 400 hp, then electrics may become more viable.
The fluid power industry in general is resistant to change, and spends very little on R&D. My new company DEHydS ( dehyds.com), Digital Electro-Hydraulics Systems should change that. As with any new business, it is an uphill struggle to execute.

 

[danhelgerson]

This has been a very informative and frustrating string. It seems clear from the comments as well as from some informal research that I have done that few people who actually need it are finding their way to the Fluid Power Society and the proper certifications that are available. The people who are getting “Specialist” certifications are using it as a sales tool and not to truly promote the proper use of Fluid Power. This is giving certification a poor recommendation. Industry needs to have more qualified people on staff as a defense against the “Specialists” that are really only out to sell components.

Unfortunately, certification sometimes shows that a person knows how to study for an exam and not that they are actually competent to do the job.

I am a Certified Fluid Power Specialist and I take it seriously. By definition, I am supposed to point clients to the best practices and the best use of Fluid Power, not to just sell a product. That is one reason I started this forum.

Thank you for your comments and ideas.


Dan Helgerson CFPS, AFPI, AJPP

http://www.cfpsos.com

 

[frans]

Sometimes hydraulics is simply more appropriate than electrics. One example I have is tunnel boring machines where I use electrical main drives where I can, but if prolonged operation at high torques are required over a wide range of speeds down to very low speeds, it does become a hydraulic system because of the time limitations on running a vector drive at low speeds and high torque - of course for a short period of time I can have comparitively far more torque with the electrical vector drive than with hydraulics. Technology advances all the time and maybe this will change. Also of course if you can keep the motor and drive components cool this becomes possible, but think underground robustness and reliability. Also often I work with 1000V systems - you try and find a 160kW 1000V vector type variable speed drive!

I do find that I can lay my hands on quite a few electrical control specialists who can put together a reliable and functional system with an acceptable commissioning problem level. I can not say the same for hydraulic systems sadly, and believe me, I have been through all the main suppliers in my area. That is why I now look to do my own hydraulic designs and I have been going through a process to gain the knowledge through the school for hard knocks.

First I started off studying the circuits I have been provided with and working out the suitability in my own mind. I found that I was often better at pointing out potential problems than my "experts"! But, I still lacked the practical nouse of what problems to anticipate where. Also, the appropriate design philosophy is still lacking a bit. I am learning though.

 

[kcj]

QQ I found that I was often better at pointing out potential problems than my "experts"! But, I still lacked the practical nouse of what problems to anticipate where. Also, the appropriate design philosophy is still lacking a bit. QQ

This thread illustrates a problem my company is having: reliance on the outside experts as 'block box' solutions, without understanding it inside the company. I think the answer is a hybrid: inside expertise to understand the application and potential pitfalls and problems as you noted, then combine that with the specialists knowledge of how to accomplishwhat we need to get done.

kcj