anachronism
Well-known member
- Joined
- May 31, 2016
- Messages
- 3,153
Learning to ash carbon has been a steep learning curve for me over recent months. In fact it's probably worthy of a thread all of its own however I thought I would share the process I went through in selecting the correct material for the trays used in the furnace.
Requirements:
Large surface area to allow large volume of carbon therefore increasing furnace efficiency and lowering cost of production runs.
Material has to remain structurally sound at 650 degrees Centigrade for long periods of time.
Material has to be impervious to the effects of high temperature ramps both up and down.
Material has to have no negative effects as a result of contact with carbon at high temperatures.
Material has to be resistant to oxidation within the temperature requirements.
Material has to be resistant to corrosion even at high temperatures.
Material has to be workable.
So firstly let's look at Stainless Steel.
Sadly the main problem is that the carbon would leach the carbon from the steel at high temperatures turning it effectively into iron and cracking. So that's no good.
Secondly let's look at Titanium.
Titanium's oxidation zone starts at 550 degrees C so given the furnace is operating at 650 degrees C that's a no go.
So where do we go from here? Having spent a fair amount of time on the net I decided to phone a couple of alloy specialists. The unanimous verdict given all the requirements was a Nickel Chromium superalloy known as Inconel 601.
http://www.hpalloy.com/Alloys/descriptions/INCONEL601.aspx
So here it is. All ready to be shaped with a hydraulic press into the right shapes. It was laser cut to the right dimensions to allow a 340mm x 340mm tray, of which there are 6. I'l post pictures of the completed trays and some pictures of ashing in progress during the weekend.
Requirements:
Large surface area to allow large volume of carbon therefore increasing furnace efficiency and lowering cost of production runs.
Material has to remain structurally sound at 650 degrees Centigrade for long periods of time.
Material has to be impervious to the effects of high temperature ramps both up and down.
Material has to have no negative effects as a result of contact with carbon at high temperatures.
Material has to be resistant to oxidation within the temperature requirements.
Material has to be resistant to corrosion even at high temperatures.
Material has to be workable.
So firstly let's look at Stainless Steel.
Sadly the main problem is that the carbon would leach the carbon from the steel at high temperatures turning it effectively into iron and cracking. So that's no good.
Secondly let's look at Titanium.
Titanium's oxidation zone starts at 550 degrees C so given the furnace is operating at 650 degrees C that's a no go.
So where do we go from here? Having spent a fair amount of time on the net I decided to phone a couple of alloy specialists. The unanimous verdict given all the requirements was a Nickel Chromium superalloy known as Inconel 601.
http://www.hpalloy.com/Alloys/descriptions/INCONEL601.aspx
So here it is. All ready to be shaped with a hydraulic press into the right shapes. It was laser cut to the right dimensions to allow a 340mm x 340mm tray, of which there are 6. I'l post pictures of the completed trays and some pictures of ashing in progress during the weekend.