Why we rejected this design over 6 years ago:
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Recently, there have been numerous attempts to copy the design of our driveshowers, and
get around the US Patent issued to us for the innovative design of our 90 degree pick-up ports. The device pictured above is just another one of the latest attempts to do so. The concept of not having to drill any holes in the anticavitation plate is appealing, but it does have its drawbacks. When we originally designed our drive showers over 6 years ago, we utilized a Computer Assisted Design Program call Pro-E. We explored the idea of coming up with a design that
would be mounted to the drive without drilling any holes. We ran the stress analysis package of Pro-E against a similar configuration to the drive shower shown above. The results told us that the shear load produced by water flowing at just over 64 MPH. would be equal to the same force that we now use to form the tubing into our drive showers. At just over 40 MPH, the force produced by the water pressure is enough to deflect (flex) a .500 inch OD X .403 ID 316 SST
tube by 5.263 degrees for every inch of unsupported tubing exposed to that water flow. It doesn’t sound like much deflection until you start multiplying it by 10 inches. The Trigonometry formula goes like this: .0175 per degree per inch. Or .0175 X 5.263 degrees X 10 inches = .921. That’s just under an inch of deflection when 10 inches of unsupported tube is exposed to the pressure of water that is traveling at 40 MPH.
I took you through the physics and trigonometry, in order to show you one of the reasons we originally rejected this design. We felt that the pick-up ports would be deflected upward enough to render them unable to supply a continuous flow of water to the top of the drive. Then when the water pressure falls low enough, the tube would return to its original form. Unless you were watching the shower while the boat was underway, you would never know if it was working or not.
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