7 Basic Valve Questions To Specify The Correct Valve

q  This webinar will be available afterwards at www.designworldonline.com & email

q  Q&A at the end of the presentation q  Hashtag for this webinar: #DWwebinar

Before We Start

Moderator Presenter

Paul Heney Design World

Richard Ronzello Peter Paul Electronics

7 Basic Valve Questions To Specify The Correct Valve

Wednesday December 17, 2014

Webinar Overview

There are many factors to consider when specifying the correct valve for your application and every application is different. These conditions could be the media, temperature, compatibility, coil voltage, wattage, or explosion proof,

even pressure ratings. All these considerations have an impact on specifying the correct valve to ensure millions of maintenance free cycles. This webinar will talk

about the 7 valve questions you need to ask.

•  Flow o  Liquid o  Gas o  CV Rating

•  Pressure o  Vacuum o  Up to 5,000 psi

•  Connections o  NPT, British Pipe Thread, etc.

•  Valve Function o  2Way, 3 Way etc.

•  Environment o  Hot, cold, extreme, o  Water resistant o  Hazardous

•  Size o  Miniature

•  Energy o  Low

•  Media o  Liquid, gas, etc. o  Temperature

Considering all the Variables

Typical Two and Three Way Solenoid Valves

Peter Paul valves are electrically operated, direct acting, stainless steel solenoid valves. (orifice sizes ranging from .6mm to ½”)

Other valves may include: Direct Lift, Linked Pilot and Internal Pilot Operated. (orifice sizes ranging from ½” to 3”)

A valve in which the orifice is closed in the de-energized (no electrical current to coil) position and no flow can exist between the inlet and outlet ports.

2 Way Normally Closed

In the energized position (electrical current to the coil) the plunger lifts off the seat allowing flow between the inlet and outlet ports.

2 Way Normally Open

There are 6 different types of valve functions:

• Two Way Normally Open • Two Way Normally Closed • Three Way Normally Open • Three Way Normally Closed • Three Way Multi Directional Control • Three Way Multi Purpose

THE FIRST QUESTION:

How do you want the valve to function, as a 2 Way NC, 2 Way NO, 3 Way NC, etc.?

Anatomy of a Valve

Threaded holes that allow connection of pipes or other components to the valve.

Ports can vary in size and thread type.

Ports

THE SECOND QUESTION:

What is the Pipe Port size? (10-32 up to 3” NPT) The pipe port size used is sometimes application dependent. If an orifice size is chosen, the port connection is sized accordingly not to restrict flow. Larger orifice sizes usually require larger pipe ports to accommodate flow or applications where multi valves are used in manifolds. NPT, BSP and SAE threads are other port options. EXAMPLE: Pipe ports are usually horizontal to the valve while some applications demand bottom ports, manifold mount and others to accommodate space issues. Manual override and metering are also considerations. Body material is also a factor for media compatibility or cost.

Coil Electric current

passes through a wire, wound around a bobbin to create an electromagnetic field which draws the plunger upward.

COIL OPTIONS Molded Coil Third Wire Ground Potted Coil & Housing Spade Terminal Coil High Temperature Coil European DIN Coil

COIL VOLTAGE

Exact coils voltages are chosen for each application. AC Line voltage or DC power supplies are generally used to provide specific voltage to a solenoid valves coil to provide the necessary power to lift the plunger off the seat to allow flow. EXAMPLE: Each coil has a plus or minus voltage tolerance. Intermittent duty coils allow a certain amount of “on and off time” to allow for higher pressure ratings that require a cool down cycle.

THE THIRD QUESTION: What is the actual voltage the valve needs to function at? (24/DC, 120/60, 230/50 etc.) Low wattage coils for power conscience applications should also be considered where battery power is required. Magnet latching coils might be another choice to consider as a 30 millisecond pulse of power will energize and the permanent magnet holds the plunger up off the seat to allow flow. Reversing the polarity with another short pulse will de-energize the valve.

The maximum difference in pressure between the inlet and outlet ports which the valve can be safely operated by the solenoid

Maximum Operating Pressure Differentials

Maximum Operating Pressure Differential

Valve  actually  sees  200  psi.  

300  psi.  Never  drops  below    100  psi.  

THE FOURTH QUESTION:

What is the maximum pressure differential the valve has to function at?

(25 psi., 100 psi., 500 psi., etc.)

Each valve is configured to allow a certain amount of flow based on pressure. Different series of valves from small to large valves are offered to meet application pressure requirements. These pressure ratings can go up to 5,000 psi. which are offered on standard valves. EXAMPLE: The pulling force of a coil has a direct effect on the orifice size and the pressure rating. Usually the smaller the orifice size the higher the pressure rating. Internal pilot valves, usually with a diaphragm or piston can achieve higher flows with larger orifice sizes up to 200 psi. A minimum pressure may be required to operate this type of valve.

Used to control flow, orifice size is directly proportional to the amount of flow. As you increase the diameter of the orifice, you increase the amount of flow. As you increase the orifice size, you decrease the pressure rating, as it requires more force to lift the plunger off the orifice.

Orifice

THE FIFTH QUESTION:

What size Orifice or Flow does the application require? (.6mm up to 3" Orifice)

Choosing the right orifice size will allow the correct amount of flow required for an application. Cv, the flow coefficient is the industry standard for flow measurement. EXAMPLE: Flow is also measured by GPM (gallons per minute) or CFM (cubic feet per minute). Whether you are measuring a volume over time, like filling a coffee cup from a dispenser or controlling an actuator to achieve maximum flow in a certain time frame.

The housing is used to create the magnetic flux required to allow the coil to act as an electromagnet.

Housing

Many options available

HOUSING OPTIONS

Strain Relief Single Automotive Double Automotive AN Connector Yoke Mounting Bracket

Standard - Grommet and Conduit

THE SIXTH QUESTION:

What electrical connection or housing option does the application require? (Conduit, Grommet, Explosion Proof or NEMA ratings for high moisture environments)

Choosing the correct housing or coil enclosure is based on the condition or environment that the valve will operate. Wet or hazardous conditions need special coil enclosures, such as Explosion Proof housings or liquid potted for submersible applications. EXAMPLE: Painted, chrome and other finishes on housings are offered as well as different color and size lead wires to better fit special applications. European DIN, spade and other coil connections for electrical wire hook up provide many choices.

Air water and other fluids compatible with standard Buna seals. Hot water, gasoline, and many oils require special seal materials.

Media

Standard Valves 0°F (-18°C) to 104°F (40°C) ambient 0°F (-18°C) to 150°F (65°C) media

Coil can be designed to tolerate much higher or much lower ambient and media temperatures. Seal material must be considered when temperatures exceed above conditions

Valve Temperature Range

THE SEVENTH QUESTION: What are the Media and Ambient, Temperature / Conditions? Media Temperature / Conditions: The correct seal material or elastomers should be

considered when the media temperature is abnormally high or low. Seal deterioration can lessen the life of the valve and also cause the sealing surface to prematurely leak. Also, seal compatibility with the media should be considered as swelling, splitting may take place over time again causing the valve to prematurely fail. Ambient Temperatures / Conditions: The correct coil temperature rating should be considered if the ambient conditions are extreme. Coil temperature ratings from 105 degrees C to 180 degrees C are offered to accommodate these high temperatures. Also the correct seal under high and low conditions should be chosen to meet these demands. Elastomers have different temperature ratings for different media for longer life.

www.peterpaul.com

On our website we have our Valve Wizard, this is an amazing tool that will help you

specify the correct valve for your application using the

“7 Basic Valve Questions”.

Q & A

Thank you for participating in the 7 Questions Webinar. We hope these have helped you and we look forward to hearing from you.

Please be sure to visit our website and the Valve Wizard. Feel free to contact

our unique technical support department and our friendly customer service department for all your valve needs.

Questions? Paul Heney Design World pheney@wtwhmedia.com Twitter: @DW_Editor

Richard Ronzello Peter Paul Electronics Richard.ronzello@peterpaul.com

Thank You q  This webinar will be available at

designworldonline.com & email

q  Tweet with hashtag #DWwebinar

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