Airpinch in Action

Tuesday, November 20. 2012

Here is the 63rd Street interactive fountain for kids (of all ages) in Jackson Park in Chicago, controlled by Airpinch valves. This fountain was created in 2001, but follow the link below to get a 2012 update. Click the caption at the top of the picture for more information.

Jackson Park Chicago Fountain

It has been a long time

Monday, November 19. 2012

It has been a long, long, long time since there has been a entry in this blog.

But that is going to change. For the past eight months or so, I have been a disciplined blogger, writing about 38 years of management every week, usually publishing on Friday.

Stay tuned, with the first one coming this week.

New Valves Coming

Sunday, January 08. 2006

Right now we are working on final production mold for 1 1/2" Airpinch valve, prototype 4" pinch valve, and 2" ID duckbill check valve. And there is more in the planning stages.

Contact us for more information.

Flow Coefficient Notes

Wednesday, September 28. 2005

A couple of times recently people have tried to apply flow coefficient (Cv) to low pressure flow. The flow coefficient is the amount of water that will flow through a device (or length of pipe, etc) in one minute with a one psi pressure drop.


[See the Airpinch website and open the Flow Capacity link on the left side of the opening page to find out more about Cv]


At low pressures, like gravity feed, Cv values are not accurate. In the extreme, if there is only one psi head pressure, then conceptually there will be no flow out of the valve ---- because 1 psi minus a 1 psi pressure drop = zero psi or no flow.

Image from www.rtlyrics.net ---- where they got it I have no idea.

Slow Painters

Friday, September 16. 2005

Have you ever watched professional painters and wondered why they are pushing the roller so slowly? Here's Why.

Most wall paints are formulated to reduce in viscosity when they are agitated by rolling or brushing so they will flow out smoothly. But go too fast and they will reduce so much that they splatter.

In engineering and physics circles, they are known as pseudoplastic Non-Newtonian fluids. Other Non-Newtonians can increase in viscosity with agitation. A good example is quick sand, which is fine sand or silt which is saturated with water, perhaps from an underground spring. If you step into quick sand, DO NOT PANIC or the quick sand will become more viscous and it may be almost impossible to escape. Instead go slowly and keep the viscosity more water-like.


Other Non-Newtonians include ketchup, blood, printing inks, some lubricants and many industrial materials. Depending on the material, Non-Newtonians can either increase or decrease in viscosity with agitation.

Richway Airpinch brand pinch valves are ideal for controlling Non-Newtonian fluids because they cause little agitation which prevents changes in viscosity.

First Entry in this blog

Friday, September 09. 2005

This blog is designed to make it easy for Richway staff members to post information that may be of value to Airpinch users and prospective users.

It will include product information, new products, applications, and other things that may be of interest.