|
Choosing a Non-Return Valve
Making a Final Choice
Once you're familiar with the different types of non return valves, it's time to make your final choice. Take a close look at your operation.
What are you running now? What will you be running in the future?
Next take a good look at all the valves that are available. Tip: don’t stop at what you see in catalogs - most companies are constantly
developing new products that may not be included in their current literature.
Whether you contact a company that specializes in the design and manufacturing of injection molding machine components, the injection molding machine
manufacturer or your resin producer, ask to talk to their valve specialist. Tell them exactly what it is you need and what you will be using it for.
Information
to have available when talking to your valve specialist
- Will this machine always be used for one application or will the application change?
- What type of resin or resins will be used.
- How shear sensitive is the material
- At what temperatures will it be run?
- What fillers are added to the resin
- Will colors need to be changed
- What is the screw RPM
- What problems have you had in the past?
- What are the specific areas of wear within your current valve? The most common wear areas are usually:
- At the base of the flute (this usually indicates adhesive wear from the ring)
- Inside the valve (usually caused by abrasive wear from materials)
- On the ring (usually indicates adhesive wear as the ring wears against the flute or the seat)
Now all that’s
left is to discuss is which features are most important to you
- Extended wear?
- Shut off?
- Shot control? Self cleaning?
- Cost?
Chances are there may be trade offs, but the right valve for the job
should be able to provide you with all, or almost all of the above .
. . and a good valve manufacturer should be able to explain why.
|
