AI-007 operation manual
Issue 1 12.10.10, HMI version 13, plc version 29
P.15 of 43
> Principle of Seam Sealing
When seam tape is heated up, the adhesive on the tape is activated. This activated tape is applied on
the water proof coating or lamination of the fabric seam under pressure. When cooled, a strong bond
is formed between the tape and the seam. This bond is so strong that it will prevent pressurized water
from penetrating the sewn seam. As a result, a water proof seam is produced.
A hot air machine, like AI-007, produces hot air with precisely controlled temperature to directly heat
up the adhesive of seam tape. The heated tape and the fabric are feeding into two oppositely rotating
rollers under pressure called nip rollers. The linear speed of the nip rollers is called sealing speed.
During sealing, hot air is being blown out from the nozzle. The hot air that actually reaches the surface
of the tape is a mixture of hot air from the nozzle and surrounding air, hence the actual temperature
that appeared on the tape is somewhat lower than the nozzle temperature. The farther the distance
between the nozzle and the tape, the higher the percentage of surrounding air becomes. On the other
hand, a higher hot air flow rate will reduce the percentage of surrounding air causing the hot air
temperature appeared on the tape to be higher. So both the nozzle position and hot air flow rate are
very important factors.
So, the major factors that can affect the seam sealing are as follows:
Hot air temperature
Sealing speed
Nozzle air pressure
Air flow rate
Nozzle position
When a consistent product is required, the combination of the above factors have to be set precisely
since their effects towards a proper sealing are all interconnecting.