Casting of wedge wire profile

[Larry767]

Hello,

My company manufactures and repairs large industrial centrifuges. We supply some customers with replaceable wedge wire screens which essentially look like a soap dish approximately 2" X 3" with the bottom made of a grid of wedge wires spaced either 0.012" apart or 0.024" apart. Our method of manufacture thus far has been to weld the wedge wires onto two short bars to give the correct spacing between the wires and form a 2" X 3" matt, then to weld that matt onto a stamped "cup". This is very expensive.

Does anyone know of a process like powdered metal or investment casting or something which would be able to mold these shapes and produce the small slot size we need on the bottom? I realize this is probably difficult to picture so if anyone is curious, contact me at larry.jorgenson@andritz.com and I can send you a photo of what I'm talking about.

I would appreciate any help anyone wants to give.

Larry Jorgenson
Andritz Bird
Saskatoon, SK

 

[MintJulep]

What is "wedge wire"?

What quantity of these things do you need?

 

[Larry767]

Wedge wire is a wire that has been shaped as follows:

Flat on top, 5 deg. taper on sides, radiused at bottom. When used to make screens with small slots the theory is the wedge shape allows a solids/liquid mixture to pass over it allowing liquid to drain. Any solids which make it through the slot will not get trapped because the wedge shape of the wire means the slots get bigger as you go deeper into the slots. The wedge wire we use is .086" wide across the flat edge and 0.137" deep. We used to buy this wire from Ulbrich but recently we have been sourcing the entire assembly from China so not sure where they would be getting the wedge wire from.

A picture of the cross section can be seen at

http://wedgewire.com/wedgewire.htm

Wedge wire is widely used to make all sorts of screens for the solids/liquids seperation industry.

We will likely buy approx. 10,000 total screens per year in batches of 2000-4000 depending on slot size.

Larry Jorgenson, P.Eng (Mechanical - U of S, 1994)
Andritz Bird, A Division of Andritz Ltd.
Saskatoon, SK Canada

 

[MintJulep]

Ok, here is my quick thought:

Machine a plate with grooves matching the wire profile at your required spacing. Possibly EDM or rolled.

Slice this plate into bars.

Align two bars in a jig at suitable spacing.

Feed pieced of wire in, and vibrate until they fall into the grooves.

Place your cup on top.

Furnace braze the whole thing together.

 

[davidh729]

From the research I've done on metal injection molding your qty's seem to be where the domestic operations will start looking at it. You may want to look at philipsplastics.com, they do metal injection molding.

Dave Hyman
iRobot Corp

http://www.irobot.com