Dosing of cyanoacrylate adhesives

Dosing of cyanoacrylate adhesives
 

With cyanoacrylate adhesives there are special dosing requirements, as these adhesives react with moisture and are highly reactive. Accordingly, we have 3-4 dosing options:

 

1. We dispense glue directly from the tube:

For example, 50g of ATK FIX glue - by installing a tapering needle, we increase the precision, but remember that high accuracy is out of the question and it depends on the person who is applying it. We take into account her skill and experience.

 

2.Dosing with the THD-4K / KE dispenser:

Pour the glue into a 10, 30 or 50 ml tube and dispense the appropriate portion. We have 2 methods, i.e. continuous dosing, as long as the trigger is pressed, as long as the glue flows out - the amount is adjusted by the air pressure and the size of the needle. Always, in addition to the portion, the density of the product should be taken into account.

The second way is to set the portion size, i.e. the valve opening time on the dispenser from 0.1s to 9.9 seconds, and also take into account the size of the needle outlet and the pressure that we give. We can obtain here an accuracy and repeatability of 0.1-0.01 ml, which are values ​​that are sufficient for 95% of the application. Filling the tubes with an amount of 1-2 a day is not a problem, but if we have several stations that use 2-3 tubes a day then you should consider speeding up the filling of the tubes and there is a very simple way to do it. It is enough to buy a pressure tank into which we put a large container with 0.5 - 2 or even 5l glue. The pressure entering the tank pushes the glue into the tube from the dispensing side, i.e. where we put the needle. It is a quick and clean way of filling glue for multiple stations, reducing glue costs.

 

Our NOTE: Just remember that the air fed into the tank or tube is free of moisture and oil, so as not to contaminate the adhesive and react with moisture.
 

3. Super precise dosing of cyanoacrylate adhesives and aggressive liquids:

Like acids, strong bases, etc. If we need a dose of glue even 0.001ml. (yes, it's not a mistake in the number of zeros), there is nothing better than the THD-6B1 dispenser. Here the principle is different from the above - the adhesive is pulled by a hose to the destination by a peristatic pump in the dispenser. We can set a continuous dosing or an appropriate portion - setting is very simple because it depends on the number of revolutions of the pump and the diameter of the dosing tube. The only downside is the dosing of adhesives to a viscosity of approx. 5000 cPs. But the big plus is the cleanliness at the point of gluing because we do not come into contact with anything other than the hose, which can later be reused or treated as disposable at the end of the day.

Watch how it works - see the video below.

4. Dosing of small and larger quantity and volume portions per day is a system that already consists of:

- pressure tank, into which we put a bottle with glue 0.5 - 5l - in extreme cases 20 liters and deliver it through a polyethylene / Teflon hose to a special head.

- THD J-90 or J-180 heads. These are special heads that allow you to dispense cyanoacrylate products and other reaction liquids such as anaerobic adhesives, acids, bases, etc. without contact with metal parts. In the first case, we have a clamping hose, which the head clamps and releases when we want to dispense, while in the second, we have a special membrane that opens and closes during dispensing,

- controller / dispenser - which controls the whole, i.e. serving portions in a continuous manner or portions depending on the demand,

It is easy to automate something like this, because the dosing itself is handled by the controller and the signal can come from a manual button, a photocell of an approaching element or a dosing robot that only gives a 0-1 signal (one zero).

 

Finally, a few words of summary, i.e. how we can dose cyanocrylate adhesives:
 

1.for imprecise but cheap dosing,

2.for dispensing in most cases and by installing the tube on the robot, also automating even more of the work,

3.super precise manual dosing,

4.manual, semi-automatic and automatic dosing on lines in large daily amounts, but small unit portions (after all, no one pours glues approx 0.5l per element)