Waterjet Group

Laro · Member

Any users with a perfect abrasive removal system?

GlassCannon · Member

If there is one out there I havent found it yet. Garnet removal is a pain and consumes alot of time for the operators. We typically dont need to vac our tanks out unless they have to be moved or repairs need to be made to the bottom, etc... We use the typical plumbing in the bottom and pump it through a dump hopper and let the solids settle and water return to the tank. One thing I have taught my guys to do is to use the machine to do some of the work. In between jobs/setups I ask them to run a stirring program, this helps tremendously to get the garnet moving out of the tank and into into the dump hopper. If you cut in one place all the time the majority of the garnet in the tank is simply stagnant. The program just needs to be set up to avoid fixtures and such and just runs a zig-zag type pattern, I raise the nozzle about 6"-12" above the water level for best results as the air infusion aggitates the tank better although it can get loud.

Hope this helps

~GC~

Laro · Member

Hello GC,

Thank you for your response. The system that you describe, is that comparable to the Aros system? http://www.wardjet.com/aros.html

I prefer the settling method more than the big-bag filtration system. About 90% of the solids settle within seconds. Only the dustcloud needs minutes to settle.

What kind of pump do you use? Our machines is equipped with an air-operated double diaphragm pump. One for the extraction, one for the return.

Are your pumps running constantly? Because of the limited filtration flow rate our pumps are running on a 40% duty cycle at max.

Best regards.

TFabian · Veteran Member

The Ebbco system is quite expensive, but it pretty much runs with minimal intervention. You still ought to drain the tank once a year though and pull out any slugs.

GlassCannon · Member

Yes, Laro, the system we use is very similar to the Aeros system offered by Ward. We installed our own due to the fact that it is about 90% cheaper to go out and puchase the pipe and fittings than to buy a pre-fab set up. Our machines run around the clock so we keep the pumps running full time as well to avoid clogging the extraction lines. We only use a single draw pump (double diaphram, Warren Rupp I believe), gravity takes the settled water back to the tank. Yuo say you are running 40% duty but in reality with 2 pumps it is 80%. We run our pumps fast enough to keep from clogging and slow enough to allow particles to settle out and can dump hoppers up to 2x per shift. Another little trick, we use the empty garnet bags in the hoppers to help in dumping (it breaks the suction), we cut them open and lay them in it.

~GC~

Laro · Member

Hello GC,

I think we have the same pumps. Our machine is also equipped with Warren Rupp pumps, they are called Sandpiper pumps.

The extraction pump is pumping 40% of the time. If we let it pump more, the filter bag floods causing a sediment on the bottom of the housing. The return pump is of the same make, but smaller and not suitable for highly contaminated fluids. We have one extraction system per waterjet, so the extraction pump is at 40%.

Is your piping system devided in sections or do you extract the whole tank? Our tank (6*3m) is divided in 4 sections, which are opened one at a time.

If you are running your pumps full time, dont you get any problems with the ball seats in the pumps? We have to replace them once or twice a year.

GlassCannon · Member

We have found that the "flap" style check valves hold up longer in this environment than the "ball" style so we have switched everything over. All of our tanks are open type tanks of various sizes with no separations. We use "dumper" style hoppers so that the water continues to circulate and we can throttle the pump back so that there is no overflowing except back into the tank. Once the hopper is full we dump it in our trash dumpster. Most municipalities don't mind taking this type of waste, barring that you are not running heavy metals such as cadmium, chromates and things of that nature, they are typical byproducts of metal plating but can be found in water jet shops as well depending on the nature of business. We have researched garnet reclamation systems but could not provide enough ROI to justify the upfront cost.

~GC~