Stand: Januar 2009
When looking for a comfortable method to fix workpieces vacuum technology is one of the first choices. For reliable results, however, you have to note a lot. Make use of our experience and have yourself helped.
Have a look at the possibilities and facts .....
What are you going to fix?
What size and weight are the parts?
Are you going to bore holes through the workpiece?
How long will machining take?
Are you going to make the same pieces or different ones?
According to the answers to these questions you must set up the components:
> Vacuum circulation (vacuum plate resp. cacuum table)
--- Sort of construction
--- Size and material of the suction area
--- Position and way of connection
> Bore-through holes
--- Partial suction
--- Mats of disposable material out of wood, paper or plastics
--- Maximum allowable size of leakage area
--- Cover possibilities
> Vacuum generation
--- Technology and size of the vacuum pump
--- Recommendation for vacuum cleaners
> Inlet, control and switch on/off
--- Hose and cable conduit
--- Control of vacuum
--- Swich manually or automatically
Finally you can determine the technical data you have to keep to in practice.
Have a look at the following pictures and details:
Date: January 2009
Vacuum plate and components
To have the vacuum circulate you need a channel system milled into the plate. The connection to the vacuum pump is made through a cut-off cock and an appropriate hose.
The plate can be made out of PVC or Aluminium, other solutions on demand.
Isolate vacuum circulation
The area of the plate, corresponding to the workpiece is isolated from the rest by foam rubber band, thus preventing unnecessary leaks.
Vacuum boxes for special workpieces
They are useful when the workpieces are always the same shape and you have got little time for changeover.
Vacuum plate for vacuum cleaners
Connect the vacuum cleaner to an adapter and have the intake flow circulate through several channels.
The vacuum cleaner must be appropriate, for more details see below.
Date: January 2009
As soon as the workpiece gets pierced, there will be holes and a leakage which weakens the vacuum. Prevent it by partial suction, where each suction spots must be isolated separately.
This method is useful with same workpiece dimensions and contours in serial production.
Sealings and mats
If some zones are not necessary for vacuum , they can be covered by airproof rubber mat.
Mats are useful when, for example, the workpiece will be pierced on many spots.
You may use different materials, but they should be permeable to air in vertical direction but little permeable in horizontal direction. The vacuum output must be raised.
Date: January 2009
Simple vacuum pump
They differ in pump technology as well as in power.
The pump you see here is suitable for continuous operation and supplies 10 cbm/h.
High performance vacuum pump
It has got a buffer storage to balance short-term vacuum differences and supplies 23 cbm/h.
Continuous leaks are problematic, the pump needs to "rest" after some time and needs to be controlled (e.g. oil level, air filter).
Compared to vacuum pumps their "air performance" is higher, but they may not be blocked continuously, because of risk of overheating. Advantage: Chip and dust can be intaken through leaks without risk.
You need industrial vacuum cleaners. They have to be proven for continuous duty and need a separate ventilator for motor cooling. The picture is just an example.
They work with compressed air, the vacuum is generated by a reverse nozzle (Venturi principle).
It can be used for small parts or with multi-arrangements. Mind that compressed air is relatively expensive, but you do not need a vacuum pump.