cnc plasma water table for stainless steel

knez57 · Apr 3, 2017

Hi all !

My company is investing in new cnc 3d bevel plasma cutting system, to replace old 2d one. It will be 2.5x10 meter of working area, as you can imagine, pretty big plates will be cut on this machine (with additional flame cutting head, plates up to 250mm thickness also). As we can imagine, this means A LOT of fumes going out. Right now we have standard dry (downdraft) table, with pretty costly air filtering unit etc. We are considering also water table with built in transporter for automatic slag removal. We saw this table in action by competition and we were impressed with minimal fumes. However, we will also be cutting stainless plates on same machine, which means water will make some sort of surface contamination from previously cut ''black'' material.

Do you have any similiar experience of that matter ? I heard there can be some additives for water to avoid that, but I d not have any informaion.

I will apreciate any comment !

DDoug · Apr 3, 2017

a water table is versatile.

When cutting normal steel, you can run the water up high enough to touch the bottom of the plate.
This will elinimate most all fumes and steam (prove it to youself by running it with the water 3" below
the bottom of the plate and you will see more steam liberated)

when doing stainless, if you would like, simply lower the water level slightly below the plate for no contamination problems.

Jimmy_pop · Apr 3, 2017

Are you currently cutting stainless steel with plasma? I dont even like to cut it with laser due to heat. Waterjet is my go-to cutting method for stainless steel because stainless steel warps at the slightest amount of heat.

Just out of curiosity, can you tell me exactly what contamination you are talking about?

knez57 · Apr 4, 2017

Hello,
seems like a reasonable solution ! Surely that means that I need to have water pump installed also, since most of the basic water tables only have one (or two) input/output pipes with flanges and thats it.
I really believe that cutting lower weater levels and also some sort of additives, most of the contamination can be avoided.

I also cut with my Flow waterjet stainless steel, but that is , when parts are more complex (i also have bevel head on). When I have simple parts, with few chamfer edges for welding, I will definitely work with plasma. I will also have Hypertherm 400 XD amperes power on my new plasma, therefore I will cut some pretty big thickness also.
About contamination: we do alot of work for pulp and paper and chemical industry, and there standards are, that no contamination of surface is permited. Believe me, if we grind black carbon steel anywhere near stainless, and we put then this part outside for one night only, next morning surface starts to brown. Surely that is no biug thing if i pickle and passivate, but still I want to avoid as much as i can. When I have my stainless parts floating in black water, I started wrong

adama · Apr 4, 2017

IMHO you need to passivated the stainless after cutting weather theres contamination or not if you want it to truly perform well - at its best.

Customer - you won't really see the difference till a month or 2 down the line in all but the nastiest of environments.

IMHO i like laser cut stainless, the mitsubishi lasers have some awsome setting and the edge comes out spectacular with no real taper at all and a very very good finish.

DDoug · Apr 4, 2017

knez57 said:
Hello,
seems like a reasonable solution ! Surely that means that I need to have water pump installed also, since most of the basic water tables only have one (or two) input/output pipes with flanges and thats it.
I really believe that cutting lower weater levels and also some sort of additives, most of the contamination can be avoided.

I also cut with my Flow waterjet stainless steel, but that is , when parts are more complex (i also have bevel head on). When I have simple parts, with few chamfer edges for welding, I will definitely work with plasma. I will also have Hypertherm 400 XD amperes power on my new plasma, therefore I will cut some pretty big thickness also.
About contamination: we do alot of work for pulp and paper and chemical industry, and there standards are, that no contamination of surface is permited. Believe me, if we grind black carbon steel anywhere near stainless, and we put then this part outside for one night only, next morning surface starts to brown. Surely that is no big thing if i pickle and passivate, but still I want to avoid as much as i can. When I have my stainless parts floating in black water, I started wrong

A water table usually doesn't use any pump.

The bottom chamber can be charged with air, sending the water up thru several siphon pipes located evenly
throughout the table.
Dropping the air pressure, allows the water to flow back along one edge, thru a series of sluice pans to remove the slag (and keep it out of the bottom chamber).

As far as edge contamination, as you are running a Hypertherm plasma, I would ask Jim Colt
(comes in here to offer help every so often) or look up Hypertherm help topics online.
I know that Hypertherm has improved things for stainless, different gas mixes, etc.

I did a short stint, as burn nesting a large plasma machine 27 years ago, and when stainless came
thru, it had much the same contamination requirements. IIRC the technique was still complete
submerging the plate under water, but the snag grinder operator had a special wheel to be used only
on stainless.

jraksdhs · Apr 5, 2017

I get stainless cut all the time on a trumpf fiber. Then again I usually work with material up to 1/4".

Search

Largest Manufacturing Technology Community on the Web

Search

cnc plasma water table for stainless steel

knez57

Plastic

DDoug

Diamond

Jimmy_pop

Aluminum

knez57

Plastic

adama

Diamond

DDoug

Diamond

jraksdhs

Aluminum

Similar threads