It is Usually Always a Clog
The most common reason for your hot glue system acting up is because of a clog. Clogs are common because you are working with glue, which is sticky and chars over time. Below are some of the most common technical calls we receive, with the solution…and you guessed it, it’s usually always a clog.
Pump is not pumping
There are several reasons as to why your pump can stop up. Honestly, it is usually dirty oily air in your shifter. However, when it is not your shifter it is usually a clog. If your shifter is running fine, but it sucked something up into the hydraulics of the pump, the pump shifter will be stopped in the top position, unable to shift down. That is because you probably have some char or debris in your hot glue reservoir and while pumping, you sucked something up into the ball check valve. You have now clogged up your pump and need to send it in for a flush and clean. Another potential issue could arise if your pump is running but sluggish. If your pump is running mush slower than it used to, it is probably because you haven’t changed out your tank filter and it is clogged. The tank filter is located on the side of the tank and filters all glue before it runs into the hoses. If that filter is not regularly changed (every 500 – 1500 hours depending on how clean your glue is) then that clog can cause pressure to back up into the tank and not allow your pump to run at full capacity.
Gun is not firing
If your gun is not firing at all, it is probably your solenoid valve. However, if your gun is firing every other time or randomly, it is probably due to a clog in your in-line filters. The in-line filters filter the glue from your hoses into your gun. These filters are there to help filter our char or debris that was missed by the tank filter or that has built up in the heated hose. If the filter screens are not changed regularly, they will get clogged up and not allow for your gun to fire properly. For example, if you need to increase air pressure in order for your gun to fire, it is probably the in-line filter clogged up. Another clog can happen in the gun manifold itself. Typically, this is only in multi-module guns. If you have a multi-module gun and the last module in the line is not firing, there is probably a clog in the manifold.
Module Drips
If your module is constantly dripping glue, then you have a clog in your module. This is most common in air open, spring close modules. A piece of char will get stuck in the seat and not allow the piston to seal tightly, causing the glue to drip out. A clogged module will need to be replaced with a new module.
Nozzle keeps clogging
This one is fairly straight-forward. If your nozzles keep clogging there are a few solutions. First, you can change out your in-line gun filters. They are probably not clean and not filtering the glue through the gun. You can also increase your nozzle diameter. If you are running small hole nozzles such as .010 or .012 diameter, try a .014 or .016 and you will start to see less clogging. However, that will lay down a little more glue, so keep that in mind when reviewing your glue usage.
The best way overall to reduce the number of clogs in your hot melt systems is to do preventative maintenance. That means cleaning your tank every month or every quarter, depending on how many shifts your tanks are running. Universal Systems makes Purge Plus tank cleaner and we sell them in a 5-gallon pail so that you are set for at least 2 – 3 cleanings. Additionally, change out your tank filters and in-line filters. These 3 tips are the most inexpensive way to keep your hot melt system running smoothly.
Packaging in the Pharmaceutical Industry
It’s been a wild ride over the last year, but the pandemic has brought on several advances in the pharmaceutical industry. Hot melt application in the pharmaceutical industry has always been important, but now more than ever. As the US pushes forward with millions of vaccines, each medication needs to be precisely packaged to make sure that it arrives safely to its destination.
Universal Systems manufactures ProBilt Zero Cavity Modules to apply a thin line of hot melt along medication boxes. Zero cavity modules have a very specific look, with a matched needle and nozzle assembly which eliminates minute material pockets that can cause nozzle clogging or dripping. They also come with an E-Z Micro Adjust option to that allows the operator to “dial in” on an exact adhesive extrusion and precise bead placement. This unique technology allows for line operators to place a small amount of glue on a small, predetermined location without creating any stringing. Typically, because of the precision requirements, most zero cavity modules are made with either a .008 or a .012 diameter orifice, so that there can never be too much glue applied.
Because zero cavities have a matched piston nozzle needle and seat, when they finally wear out, most manufacturers require customers to replace the entire module. Universal Systems does not. We manufacture a rebuild kit specifically for zero cavity modules for a fraction of the price of replacing an entire module. Check out our rebuild kits here: https://www.ussefl.com/products/hot-melt-modules/module-rebuild-kits/.
Not many hot melt application manufacturers offer zero-cavity modules. Luckily, here at Universal Systems we have been manufacturing this specific module for over 25 years. If you would like to learn more about zero cavity modules or get a price quote, please reach out to sales@ussefl.com or call (561) 272-5442.