Folding is an essential operation that conditions the workflow in a sheet metal workshop. The challenges are numerous: productivity, precision of folded parts, safety of the operator, etc.
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Almost all sheet metal plants use press bending machines at this production post. Two main technologies are proposed by the manufacturers: machines with hydraulic drive and those with electric drive by servomotors.
The main advantage of hydraulic press brakes is to offer very large folding capacities. On the other hand, despite the higher purchase cost of electric press brakes, the use of servomotors instead of hydraulic cylinders brings productivity, energy, flexibility and maintenance gains. And the capacities of electric press brakes can be of up to 4 meters of folding and a force of 300 tons.
Mauricio Gutierrez Matta, Export Manager, SafanDarley, builder-developer of hydraulic and electric press brakes, agreed to enlighten us.
There are 5 axes of differentiation between electric press brakes and hydraulic press brakes:
On average, 60% of the operating time of a hydraulic press brake is used for adjustment and maintenance operations: programming, changing of tools, handling of parts to be bent, oil change, etc.
The productivity of the equipment is strongly impacted. The hydraulic system works continuously even when the machine does not bend. This results in considerable and unnecessary electricity consumption (oil to heat, machine idle, etc.).
Mauricio Gutierrez Matta indicates that, on the other hand, "the energy consumption is very low on an electric press brake, because the servomotors consume energy only during its operation!"
The bending is a deformation of the slider which is observed on all machines with hydraulic drives. Most manufacturers of hydraulic press brakes offer mechanical or hydraulic "de-bending" systems. There are actually solutions that consist in compensating for this phenomenon by a reverse force in the worktable. The adjustment is manual or automatic, according theoretical bending rules.
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"We have invented and patented for our electric press brakes a system of pulleys and belt that avoids bending in 99% of situations"adds Mauricio Gutierrez Matta.. "The force is distributed all along the sheet to bend evenly. The removal of the bending allows an improvement in the precision of the bent parts."
The manufacturer who invests in a press brake determines the capacity of the machine according to the largest part to bend and the thickest material to be bent. However, on a hydraulic press brake, energy consumption will be similar from one piece to another. On an electric press brake, servomotors consume only the energy required to bend the work piece. It has therefore to be taken into account in the choice.
Folding operator safety on press brakes is often considered by industry as a brake on productivity.
"The protection system installed on most machines reduces productivity. This is a passive solution that works according to the height of the tooling. It must be set at each tool change left and right. A wrong setting defaults the machine." »detailed Mauricio Gutierrez Matta.
And to add that« "SafanDarley has integrated in its machines a security system that requires no adjustment or use of a pedal. The descent of the slider can even be done in high speed up to 1 mm of the sheet. It's a security system that increases productivity instead of decreasing it!"
Hydraulic press brakes require regular maintenance, especially on the hydraulic part such as valves, tanks, pumps, filters and seals. In addition, the loss of pressure in the cylinders causes the loss of oil, which spreads around the machine. The challenge is to be able to reduce maintenance costs, without accident and without having to immobilize the press brake.
As a conclusion, Mauricio Gutierrez Matta differentiates the two technologies by stating that "the electric press brake is the most relevant solution up to lengths of 4 meters. The economic gains are very important because of the reduction of the energy expenses of about 30%, the reduced maintenance and the flexibility which makes it possible to increase the productivity."
We are looking at getting a new press brake and wanted to reach out for some user thoughts.
We started with a new 24 ton Atek and then purchased a "like new" LVD strippit SP540 The strippit is 7 years old but has next to no hrs on it. I would keep it but strippit has no desire to support it and I am not in a position to maintain it with no support. We are a small shop that tends to use newer gear that has good service.
Requirements:
4-6 foot bed
40-50 tons
Basic back gauge (CNC would be nice but not a must)
We do simple forming. nothing crazy complex
Would like to be under 40k
Looking at selling the new Atek and the Strippit to purchase new.
Any pointers on brands? Not opposed to used so long as it would be a well supported system.
Thanks!
Any pointers on brands? Not opposed to used so long as it would be a well supported system.
We have 24 Amada Press Brakes and 1 Safan Press Brake. Can't say anything bad about any of them.
Looked at LVD's new line up in Buffalo a couple of years ago. I really like what I see but adding another brand just isn't in the cards right now because of labor shortages and training issues with too many controls.
The Safan is in house to show Amada there are way faster Light Curtain machines out there and they had better catch up. Safan offered to place it on our floor for 3 months for a test...ended up buying it. Very nice production machine. But the Amada ATC do out produce it but the HFE and HFB series machines in most cases are no match for the Safan.
Look at them all and make the right decision.
Sounds like you're a perfect candidate for an Accurpress. The sheet metal shop I deal with uses them and they seem very well made, and the control is perfect for small run custom stuff.
They are quite expensive for what they are, if you actually option them out in a way to use them.
I've got a quote for an Accupress still sitting on my desk. By the time you option out the Accurpress to match the 'base model' MVD (what I ended up purchasing), you're at almost $30k more for the Accurpress, and even then it's not even equal - 8" throat on the Accurpress, 15.75" on the MVD. 8" stroke on the Accurpress vs 10.25" on the MVD. Accurpress was almost pounds lighter. Less clearance between the housings, etc.
When I was trying to buy 20 year old used, the Accurpress made sense. They're everywhere, and you can pretty much rebuild them from the Grainger catalog. But, when I changed my mind and decided to go new, it didn't even come close to being the right choice for me.
I`m interested to follow this thread as, having successfully got a new CNC mill in I can turn my attention to dreaming about upgrading from our 12 ton 48" Atek. (This is a large biomedical research centre and hospital shop so we dream and write applications for funding) We're limited for space and always are doing onesie twosies so being able to accurately program the press travel (is that the R axis?) would be a huge addition. The Atek has a CNC backgauge which I wouldn't do without but we spend a lot of time futzing around with the travel stop and 12 tons is just not quite enough for quite a few of our jobs. I like the idea of electric press brakes for small scale low duty cycle usage. In the 25-40 ton 40-51" category I see the Trumpf which was $140K in , and the Mitsubishi Diamond BB series for which I didn't get a price when I was last looking. The CoastOne C15, which at least is sold by the guys who sell MVD hydrualics presses, looks good and the smaller C9 is only $50K per their website. And there's the Accurpress at 25 tons and 51". If anyone has a ballpark knowledge of these prices I'd love to hear. I'd go look myself but I need to identify funding first as I don't like pestering sales guys with my dreams too much.
TruBend Series | TRUMPF Trumpf
Diamond BB Series - Electric & Hybrid Press Brake Machines | MC Machinery Systems
Electric Press Brakes – International Technologies, Inc. - Coast One
Accurpress sales man came by and I told him what I was looking for. Blah blah blah and he had horrible bad breath. Kept my distance. Asshat never got back to me with a quote. Looked seriously at Amada. Critical questions got skirted around and never answered. Trumph had the highest price and the True Bend footprint with 10 foot was smaller than the Amada 8 foot. Have the Trumph.
Decide what you NEED it to do.
If it takes seconds to program a good part the first time, you will like it.
After sub'ing out press brake work for many years, I finally bought one. I ended up settling on used Amada. Their earliest RG series press brakes are still supported by amada with all parts available. There are several used equipment resellers who specialized in refurbishing the Amada brakes because of the parts availability aspect and they they are dead nuts accurate and repeatable. There are even now 4-6-axis backguage suppliers who have popped up selling killer retrofit back gauges for these older Amadas. So there is room to grow with this machine but the basic backguage on a RG50 will be a nice feature for your current tasks.
If you searched, you should be able to find a clean RG50 well within/under your budget.
MachineTools.com, The metalworking machine & tooling marketplace for new & used equipment.
I am almost 100% sure this is one of the refurbish companies that is super into the Amada equipment. Super knowledgeable and professional.
AMADA RG-50 Press Brakes Used - Excellent # - MachineTools.com
I wanted to buy from him when I was finally ready to buy but he didnt have what I was looking for at the time.
amadas are up acting, right? how much does that affect operations?
It makes no difference.
In all my years of sending out parts, they were all produced on down acting accurpress, trumpf or cincinnati presses. Down acting was the default way my brain saw parts being processed. The upacting was foreign upon first seeing it but my brain and eye quickly adjusted and it makes no difference. The way the amada tool holders slide along the upper beam, you can do some very deep boxes and very unique parts compared to the continuous style punch holder typical on a 7 series rocker style accuress.
amadas are up acting, right? how much does that affect operations?
The LD Series and RG are up acting. The HFB-E's and HG series and many others are all down acting.
Productivity depends on the parts. I have 1 guy who will only run a up acting.
The biggest effect on productivity is the Light Curtains. If you are starting out with no Brake or Tooling look at common shut height tooling. We are making the switch where we can right now. I figure we'll need to invest about $500K to completely switch over.
Light Curtains now days are a must. Our last OSHA inspection we got tagged on 2 machines out of 25 (10 of our older machines do not have light curtains). $700.00 per machine. While she was explaining her findings she stopped midsentence and said "Why are you glaring at me?". My reply was "you are going to put me out of fucking business unless you write all my competitors the same citations". After a rather harsh conversation with her she allowed me to pick the 2 machines we would take out of service. She asked why I wanted and I explain to her I would just push them right in the scrap trailer while she watched.
Well my guys calmed me down and we simply put them in the backroom while she watched. Later we traded one in on a new Hymech Saw. The other is still sitting in the back room. No way am I going to put light curtains on a 20 year old Amada LD. Thinking about taking it home...
Hey Scruffy887, (or anyone else) could you comment on bend angle accuracy with a modern control? Is it reasonable to be within, say, one degree (.018" at the end of a 1" long flange) on your first bend if you have all your tooling parameters and thicknesses set up properly?
It is safe to say you will never get it right on the first part no matter what. Too many factors weigh in...biggest in my opinion would be the material thickness, next tooling condition and crown compensation.
On our new Amada HG ATC machines .5-.75° after dialing it in...
The software is intentionally set-up to leave the angles open incase the material is running heavy. This saves the tooling from abuse on accident. We program everything off line for the HFB, HFE and HG Machines.
I did see a demo at Strippit LVD about 3 years ago where they had a camera that followed the material and got the bend angle perfect every hit. The operator formed 2 pieces at once and the angles were perfect on both parts...needless to say the parts were not to print however but it did not wreck the tooling or cut the parts in half.