5 replies to this topic

[jprocess]

Dear All,
I need information regarding to 3 and 4 way valves including their application,shape,and etc.
Thanks in advance,
Best Regards.

[Zauberberg]

"Control Valve Handbook": http://www.documenta.../book/cvh99.pdf

Three-way valves are often employed for hot fluid flow control through process reboilers. One Google search will come up with all information you need.

For example:

DIRECT-ACTING 3-WAY VALVES

Three-way valves have three port connections and two valve seats. One valve seal always remains open and the other closed in the de-energized mode. When the coil is energized, the mode reverses. Various valve operations can be obtained according to how the fluid medium is connected to the working ports. The fluid pressure builds up under the valve seat. With the coil de-energized, a conical spring holds the lower core seal tightly against the valve seat and shuts off the fluid flow.
Unlike the versions with plunger-type cores, pivoted-armature valves have all port connections in the valve body. An isolating diaphragm ensures that the fluid medium does not come into contact with the coil chamber. Pivoted-armature valves can be used to obtain any 3-way valve operation. Pivoted-armature valves are provided with manual override as a standard feature.

From: http://www.omega.com.../techprinc.html

[Art Montemayor]

jprocess:

You have to give specific, and relevant information about what you need if you expect accurate and useful responses. Are you talking about:

1. the color of 3 and 4 way valves?
2. The weight of 3 and 4 way valves?
3. The shape of 3 and 4 way valves?
4. The price of 3 and 4 way valves?

Do you now see the point I’m trying to make? We are not magicians or mind readers. We don’t know what YOU are thinking or what you possibly intend to state. You must state what you specifically need. This is supposed to be an engineering Forum and we are all supposed to communicate as engineers. Engineers are expected to be specific and to the point – with logic, reason, and complete, detailed explanations. My reason for writing this is to let all engineers know that this is the minimum quality of communication that is expected of them. If we don’t communicate well and accurately, we can’t expect to receive accurate and correct responses from our queries. And if that is the case, how then can we resolve problems without any accurate responses? For example, just exactly what do you mean by “etc.”?

There are 2 basic divisions of valves:

1. Block and throttling manual line valves; and
2. Automatic control valves that operate through an actuator receiving an instrumented signal.

If you are talking about block and throttling manual line, 3 and 4 way valves then you have the following main varieties:

• Plug;
• Ball.

If you are talking about 3 and 4 way automatic control valves, then you are mainly referring to the globe variety. The same applies if you are talking about solenoid-actuated, snap-acting valves. If that is what is concerning you at present, then Zauberberg is giving you a good source for information on getting familiar with this type of valve.

Please give us the necessary details and precise information on what you mean and what is your purpose for employing these valves. We can give you a world of experience and expertise on these type of valves - and for FREE. But you have to contribute at least the same amount of effort as we do in answering your request. If you turn in a half-hearted, badly and sadly-worded query, what do you expect to receive?

We await your reply so we can help out.

[jprocess]

Dear all,
Thanks a lot for your answers.
You are completely right.I will try to make my questions with more details in the future.
But as you see i limited my question about these valves to their application and shape.
Warm Regards.

[Adriaan]

In practise where I work 3 and 4 way valves are used for specific purposes;

> 3 way valves for switching between twin additive tanks (one is used while the other is filled and homogenized; the system uses two coupled 3 way valves - additive to system on one, water to additive tank on the other)

> 3 way valves for switching between a feedline and a purge line

Both are similar T shaped valves (VERY different sizes, mind you), ball valves with a 90' angled hole in them. So turning the handle 90' switches from one source to the other (with sources at the left and right side of the T and the output at the bottom).

> 4 way valve for inverting flow direction (of cooling water) through a condensor (which makes built in brushes run through the pipes to clean them)

The valve is HUGE and basically consists of one plate with two holes at one side (one for cooling water feed, the other for runoff), a plate with a hole facing it and a swingtube. The swingtube moves from one hole to the other (using an electric motor, timer controlled).

[Adriaan]

Oh! Nearly forgot this TINY three way valve on the Tiptronic burette; its about the size of a 50 Euro cent coin in diameter. In one position its used to fill the burette, in the other position to dispense from the burette.