I ask Fred, "Why do suction press rolls have to be made out of metal?"
He pointed out the answer in his water bowl, which is always on the floor in the front seat of the car and is made of plastic (although he is a Cocker Spaniel/Terrier cross, sometimes he acts like a Pointer).
In it, I saw a pattern that looked something like this:
This is the end view of Fred's suction press roll. The roll is made out of carbon fiber. It does not have a drilled cover, the pattern of the carbon fiber is such that it is porous (think of how a press felt is constructed). The thickness of the shell is not shown on this simple diagram.
The sectors serve two purposes. First, the cross members serve to strengthen the roll, because now without a suction box, we can have cross members in the roll. Then, these same cross members create multiple chambers (sectors) in the roll which will replace the suction box. Likely there will be many more sectors than I have shown.
Let's say the sector in the upper right (the 1 - 2 o'clock position) is where we want suction. On the ends of the shell, as sectors pass this area, they are exposed to vacuum applied on the ends of the roll--this works much like a suction chamber does now. Then it get interesting--at the sector at the lower left (the 6 - 7 o'clock position) the sectors are exposed to high pressure air which blows the chambers out into a saveall pan (not shown).
Advantages as compared to metal:
1. Light weight
2. No corrosion
3. Self cleaning
4. No suction box seals
5. No internal showers adding yet more water
6. Much lower WK2 (torque) requirements
1. The suction area is not as tightly defined (depends on how many sectors there are)
2. A new device, an end seal, has to be developed.
How do you make this roll? Likely by using a 3-D printer that prints it axially, that is coming out of the page when looking at the diagram above.
Hey, if Boeing can make a plastic airplane, this ought to be easy.
This is what we do at the Light Green Machine Institute. This may be the best thing we have conceptualized all year. However, you never know, so you need to come to Raleigh, 16th - 18th of October (less than two weeks away)--to make sure you don't miss anything!