Looking for some technical expertise on water pressure / abrasive combinations to cut into 3/8" wall MILD STEEL square tubing 8" x 20". The thing is I have 350 - 3/4" Dia. holes to cut on one side without piercing through the other side. and the parts are 960" long ( yeah 80 feet). I am going to set up a track system to support the part as I am restricted to 120" cutting area due to the size of the machine, this will involve removing the holding tank (waterjet table) as well. Looking for a way to avoid using a trolly system on the ID of the tubing to deflect the stream from cutting the bottom side. I can absolutely sacrifice the cutting speed that's not an issue.
oferiniowa said
May 8, 2013
I've cut holds in 3/8" square tube in one wall only. I just set up with the tube wall thickness and go. It puts a mark on the inside surface of the opposite wall but does not go through. I've made holes as small as 3/8" diameter and large enough to catch the radius of the tube. It is very loud and you'll have water coming out the end of the tube, but it works very well.
We run 60,000 PSI with HBA100 abrasive 0.7 lbs/min on a FlowJet. You may want to play with your pierce time and dwell time at the end of the cut, or make your lead in and out lengths to prevent the stream from being in the same area too much.
OPTION WATERBOY said
May 9, 2013
Thank you for your reply,
I run 60,000 PSI with 80 HPA abrasive 1.0 lbs/min on a FlowJet.
Hell Yeah it's loud! Double hearing protection for me ! Amazing how the shop clears out when I do these jobs, and thank God I have labourers to clean up the mess afterwards.
I have cut holes in square tubing tubing and Large Diameter pipe before but I have always had to put scrap metal inside to deflect the stream, especially during the peirce. ( I've had holes blown right through to the otherside on 10" dia x 1" wall thickess pipe before). I am going to try your suggestion on a test pce. This is a very large job to do, as I have four of these parts. The set up involved is not someting I would like to do all the time. I figure this job will isolate the machine for atleast a week.
Maxxheadroom said
May 21, 2013
I have cut many many tubes, I find the best way the same as you is to armor the bottom of the tube with scrap material. We consider this when quoting jobs. The other thing I do when cutting tube is I tack a plate on either side of the tube with a small hole cut on either end. While there is still some spray that comes out of the holes it greatly reduces the mess otherwise made, and greatly reduces the amount of noise.
TFabian said
Jun 20, 2013
The other thing to do is minimize your delay values and avoid stationary pauses. This will minimize the divots left on the opposite side.
Sorry for such a late reply but I am a fairly new user, some of this may help for future work though.
We do quite a few jobs that require cutting of tube, pipe and so on. We use carbide blocks/funnels to block the stream. It holds up much longer than sacrificial steel or other materials and can be made into any desired (reasonable) shape. We typically use an indexing rod to attach the carbide and for positioning under the jet on tubing, arm attachments for our 5-axis work and a "bucket" full of spent nozzles/scrap etc for other large open air type cutting that we can wheel around under the part to follow the stream.
We run 60,000 PSI with HBA100 abrasive 0.7 lbs/min on a FlowJet. You may want to play with your pierce time and dwell time at the end of the cut, or make your lead in and out lengths to prevent the stream from being in the same area too much.
Thank you for your reply,
I run 60,000 PSI with 80 HPA abrasive 1.0 lbs/min on a FlowJet.
Hell Yeah it's loud! Double hearing protection for me ! Amazing how the shop clears out when I do these jobs, and thank God I have labourers to clean up the mess afterwards.
I have cut holes in square tubing tubing and Large Diameter pipe before but I have always had to put scrap metal inside to deflect the stream, especially during the peirce. ( I've had holes blown right through to the otherside on 10" dia x 1" wall thickess pipe before). I am going to try your suggestion on a test pce. This is a very large job to do, as I have four of these parts. The set up involved is not someting I would like to do all the time. I figure this job will isolate the machine for atleast a week.
Sorry for such a late reply but I am a fairly new user, some of this may help for future work though.
We do quite a few jobs that require cutting of tube, pipe and so on. We use carbide blocks/funnels to block the stream. It holds up much longer than sacrificial steel or other materials and can be made into any desired (reasonable) shape. We typically use an indexing rod to attach the carbide and for positioning under the jet on tubing, arm attachments for our 5-axis work and a "bucket" full of spent nozzles/scrap etc for other large open air type cutting that we can wheel around under the part to follow the stream.
~GC