Silenta Screen

The single laning of bottles with standard guide rails causes the following disadvantages:

• Collision effect
• Deceleration
• Tilting effect

This causes:

• Fallen bottles
• Noise
• Abrassion

The collision effect is caused by the product running against an angled guide rail.
At a pitch of 1 : 5 and a Slat speed of 1.500 mm/sec, the collision speed is 300 mm/sec. and the Bounce back speed

• 150 mm/sec with standard guide rails
• 30 mm/sec with the Silenta Screen guide rail
  
  

The slowing down of bottles is a special problem because a higher slat speed is necessary to achieve the required line speed.

e.g., at a required slat speed of 1.000 mm/sec the system must be adjusted to a speed of 1.400 mm/sec. The sliding slat chain running under the bottles disturbs them, especially PET bottles with feet. The braking effect is caused by friction on the bottle walls.
The friction coefficient sways between 0,14 and more as 0,50 (Glass bottles with a friction base on dry steel guide rails).
Exactly these differences in the friction coefficient causes the difficulty to find the optimal speed adjustment of the conveyors.
For single laning it’s necessary that all bottles touch the guide rail. There must be gaps between the bottles so that the bottles on the outside can reach the guide rail. Slowing the bottles down, closes or reduces the gaps differently, depending on the friction coefficient from bottle to bottle.
It is considered helpful that the friction between bottle and guide rail causes the bottles to rotate.
The tilting effect cause the bottles to fall.
It is caused by the guide rail pressure point, not being at the center of gravity of the bottles.
The energy to transfer the bottles comes from the adhesion and or friction of the bottle base on the conveyor chain.

When the bottles meet the Silenta Screen Guide rail, the bottles are not slowed down but slightly accelerated.
Through this, gaps are made behind the bottles that are running against the guide rail.

Advantage of this new system
Reduction of the collision effect to 1/7th of the original.
Therefore less disturbence and lower bounce back effect.
Considerable noise reduction.

The use of a new material is the reason for the improvement. This was tested at the Fachhochschule Cologne according to DIN 53512. By using a parallel running guide rail there is no slowing down of bottles. The line speed of a PET plant was increased from 30.000 to 45.000 bpm.