Cyclone

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Building the Cyclone for GEK v2.0

 

 

Parts needed:    

     - Top Cylindrical vessel

     - Bottom Taper

     - 5" end plate for top of cyclone

     - Square taper tube for tangential entry to cyclone

     - Square flange for above tube

     - 2" x 4" black pipe nipple

     - 1" coupling

     - 1" x close nipple

     - Glass Mason jar

 

See here for the CAD files of the sheetmetal parts.

 

If you want to design your own cyclone, the dimension ratios are explained Tom Reed's Handbook of Downdraft Gasification.  The specific except on cyclone dimensioning is here. 

 

The most difficult part of cyclone making is the cone taper.  See here for a wiki page with instructions for how shape and cut the cone taper.  You can bend the cone with a slip roller or pound it out a pipe or anvil. 

 

Once you have all these parts, or have the kit from APL, or have made your own to new dimensions, follow the below instructions.

 

 

1. Assemble cyclone body

• Clamp top end plate into top of cyclone cylinder.  Slag side of plate should be down.  Make sure to center tabs in slots around the perimeter.
• Tack end plate and cylinder together.  Tack down side seam, making sure overlap stays consistent.
• Weld 2" x 4" pipe nipple into top of end plate to make cyclone outlet.  The threads on the nipple should extend exactly 1" above the top of the end plate, and be exactly perpendicular to the top plate.  Reconfirm this alignment from the outside as well as the inside of the cylinder.
• Tack together the tapered cylinder.  You may find hose clamps, tie downs, or other clamping devices to help hold the taper together and aligned before tacking.
• Bring the top cylinder and bottom taper together to assess alignment.  The weld is usually easier if the taper lip is slightly larger than the cylinder, allowing the cylinder to slip down inside it about 1/8".  It is also fine if they meet edge to edge.  The important thing is that the seam is smooth and even.  Any method that achieves this is fine.
• When happy with the alignment, tack into place, then stitch weld in stages to prevent warpage.

 

          

 

 

2. Attach inlet to cylcone body

• Align tangential inlet tube into topside of cyclone.  The lip of the inlet tube should insert just inside forward edge of the square entry hole, and all the rest of the edges should conform with the sides of the cylinder.  Bend and coax as needed.  The goal is to have a smooth transition surface all around the joint for smooth gas flow.  The top of the square inlet tube should also be parallel with the top of cyclone, and without twist, so that it will align properly with the gas cowling.
• When happy with the alignment, tack into place, then stitch weld in stages to prevent warpage.
• Align and weld square flange onto inlet tube.  Use this weld step as an opportunity to make sure the cylcone is aligned parallel with the gas cowling.  Alignment is usually helped by bolting the cyclone flange to the gas cowling flange, then holding the cyclone in place while tacking.  Once tacked alignment is confirmed, weld into place.

 

      

 

3. Attach condensate trap on bottom of cyclone

• Weld half of a 1" coupler into the bottom of the cyclone's taper.  Use a 1" nipple screwed into the coupler while welding to make sure the coupler is aligned in the bottom of the taper. It is visible in the tip of the cyclone taper in the left photo below.
• Weld a 1" close nipple into the steel ring lid for the Mason jar