Why do you say not to use Clemco or Marco deadman valves?

Bleeder – Not compatible to our normally closed system.

Thank you for your posting and interest in the Schmidt product line and community.

Axxiom Engineering Staff

Axxiom Manufacturing Inc
1.800.231.2085
Fresno, TX

Copyright 2008 Axxiom Manufacturing, Inc.
Axxiom Manufacturing, Inc. is the exclusive manufacturer of Schmidt products. Certain products manufactured by Axxiom Manufacturing Inc are protects by patents pending in the United States and other countries. Axxiom, MV, MV2 and Microvalve are trademarks and Schmidt, the stylized "S", Combovalve and Thompson Valve are registered trademarks of Axxiom Manufacturing, Inc. All rights reserved.

What does bleeder mean, and what is normally closed?

The Clemco handle is far easier to hold and my blasters wont use your orange one, unless they tie it down, and i'm worried about an accident. Please do you have an electric handle my men will actually be able to hold, on a blast hose, and safely?

Using a "bleeder" type deadman is not compatible with our normally closed system. It can create an unsafe situation as well as voids any and all warranties.


A bleeder deadman works on the principal of back pressure.
In the off position there is a constant "bleed" of control air out of a hole under the handle.
When the handle is depressed, a rubber plug covers the bleed hole and creates back pressure down the return line to activate the controls of the blast unit.
When the handle is released, the pressure in the return line is vented out the bleeder hole to allow the controls to shut off.
During this process, not only is the return line venting but the supply line is also escaping from the same hole. Therefore both lines compete with each other to shut down the blast unit.

A hazard of this design is that any foreign material in the control lines can plug the bleeder hole. Should the bleeder hole become plugged the blast hose will engage. There have been reports that in certain atmospheric conditions frost or ice have formed and plugged these bleeder holes.



SOLUTION:

A normally closed deadman, such as the G2 from Axxiom, works on a different principle.

In the off position the supply air is mechanically shut off inside the deadman.
When the handle is depressed an internal valve is opened allowing the supply air to be transferred to the return line to activate the controls on the blast unit.
When the handle is released the internal valve shuts the supply air off and simultaneously opens a dedicated passage to vent the return line to atmosphere allowing the blast unit controls to turn off.

The mechanical shut off of the supply air as well as the venting of the signal air through a dedicated vent hole is our preferred design.


© 2009 Axxiom Manufacturing Co., Inc.
Axxiom Manufacturing, Inc. is the exclusive manufacturer of Schmidt® products. Certain products manufactured by Axxiom Manufacturing Inc are protected by patents pending in the United States and other countries. MV is a trademark and Schmidt, the stylized "S", Axxiom, Combovalve, Microvalve, MV2 and Thompson Valve are registered trademarks of Axxiom Manufacturing, Inc. All rights reserved.