electric proportional control valves

If the valve is operated within the temperature limit specifications, nothing.

Do you have a real question?

Im dont a deploma in engineering technology and one of the questions was How does operating temperature affect the operation of these valves

Dependant on the exact type of valve, temperature can cause problems even if operated within manufacturers recommendations.

Besides the obvious of varying coefficients of expansion between two or more close tolerance components, there is also the problem of 'thermal shock' which can either jam a valve solid OR give uncommanded operation OR reversed operation with disastrous results (crashed airliners)!

Each potential issue is case specific and there are any number of potential issues!

You could end up doing a lot of research to answer that question!

Thanks for your help it came in very usefull .

Valves are made of different materials which has different thermal expansions and young modulus dependence on temperature. If this is not enough we end up using some time rubber and plastic material which causes plasticizer extraction and man made failure of the electronic valves.

Failure is complex and is the reason by from known sources and optimize and test in recommended temperature range of the manufacturers to understand its usability under your use conditions.

Parker Hannifin seem to have the monopoly in this area but it should be stressed that economics should play NO part in deciding a valves suitability when it comes to aircraft!

These valves are not for aircraft use but I want to have radio control similar to that required for aircraft, and price is very important when it comes to using 20 of them in a machine for a ground application if I want to be competetive.

Hi Jim

You will need to, firstly, start with the pressure and flow requirements of the valve, i.e. What are the requirements of the actuator that the valve needs to control?

Secondly, you will need to work out the response characteristics that are required and:-

Thirdly, how you will provide the proportional valve with a compatible signal such as, 4-20mA, 0-10V or 10V bipolar and find a radio control that will do that!

To my knowledge, you won't find a valve that will just 'plug into' a radio controller. It can be done and has been done but you will have to come up with the interface to make it happen!

Good luck

I agree w/ the comments and second the response from Beej50. Furthermore, I've seen many applications that failed due to ignoring the manufacturer's specified range or limits -that's why they take the time to research & print this info. (sometimes incorrectly). Also, I've noticed that many applications fail to exercise the component as recommended in addition to paying no attention whatsoever to maintenance!