Thursday, August 17, 2017

Air pressure for Nordson ProBlue Melters

Pressure Gauges

If your pump is shifting erratically and/or the glue output is not up to par, check the following in order to reach maximum adhesive output:

  • Verify the factory's air is clean and dry.
  • Verify the air supply is capable of providing a maximum of 6.2 Bar (90 psi) of non-lubricated air.
  • Read the specifications on your specific adhesive and what is recommended.
It is suggested that an isolation valve be installed in the factory air supply line immediately before the melter.

Minimum operating air pressure is 0.7 bar (10 psi).  Operating at pressures lower than the minimum may cause the pump to malfunction.

Still having issues, please call us.

Angela Wagley

Friday, August 11, 2017

Maintenance on Nordson Glue Melters

It doesn't matter whether you have a newfangled glue melter or and old dinosaur of a glue melter, proactive maintenance is key to long life and reduction in breakdowns.

Do you change the oil in your car within OEM recommendations?  You know what will eventually happen if you consistently provide poor maintenance to your automobile.....you have an expensive engine repair bill.

A glue melter is no different.

Periodically flushing the tank, changing the tank filter and inline filters is key to lengthening the life of a glue melter and also will reduce the amount of times the unit is unexpectedly down.  

Other ways to reduce clogging of nozzles is to verify the adhesive is stored in a clean protected environment, the glue tank is kept full and the temperature settings are within the recommended temperatures of the adhesive specifications.

Some facilities use auto-feeders for the adhesive to reduce the amount of contaminants entering the glue tank.  In addition, these provide a safer environment for the workers.

All of these steps are quick and easy to incorporate.

If your unit has too much build up of char, we can provide rebuild services to delay the purchase of an expensive new unit.

Have questions or need assistance.... please call Keystone Industries.


Angela Wagley

Tuesday, April 11, 2017

Sources of Adhesive Failures

Sources of Adhesive Failures | Keystone Industries

Industrial adhesives are normally reliable and dependable for consistent bonding. When used correctly, industrial adhesives can save money, time and effort.

Problems can and will arise when adhesives are used improperly which will cause complete chaos on the most sophisticated packaging line.

Areas to investigate to determine the root cause of the adhesive problem:


Impurities in either the dry adhesive, the substrate or the melted adhesive can cause loss of adhesion. Verify adhesive storage containers and substrate materials are covered properly to reduce the entrance of foreign materials. Some examples of foreign materials are box dust, milled food products, and any type of oils or impurities. Keep lids on glue melters closed to reduce the introduction of foreign materials into the glue tank. Any foreign material in the glue melter can char and plug the pump, hoses, filters, and applicator heads.

Adhesive Type

When speaking with your adhesive vendor, provide a sample of the substrate(s) to which the adhesive will be applied. There are many varieties of adhesive and the adhesive must be specific to your particular substrate(s) in order to bond properly. Certain adhesives are not compatible with certain substrates and will have no bond strength.

Mixed Adhesive

It is not ideal to mix any adhesives. If changing adhesives, always flush your glue melter completely to remove the old adhesive before using your new adhesive. Mixing adhesive chemicals can cause bonding issues and some types adhesive when mixed together can destroy your melter system.

Set Temperatures

Read your adhesive specifications and use the recommended set temperatures. Heating an adhesive too high will cause char issues, cause degradation of the adhesive and thus, cause bonding issues. Heating too low may cause bond issues.


Bonding issues can occur in cold environments or where fans or HVAC vents are blowing directly on the glue applicators. Check your set up and verify any type of fans are moved to face away from your glue applicators. Moisture is another factor that may adversely affect the adhesive bonding. Check the adhesive specifications and know your adhesive.

Amount of Adhesive

Are you using the proper amount of adhesive on the substrate? This is a question to pose to the adhesive vendor in the beginning. There are different choices for how to apply the adhesive to gain the bond strength needed. You can use a stitch, dot, spray, slot or continuous bead pattern. If you don’t need full coverage and are looking to save money on adhesive, consider a stitch or dot pattern. Testing in advance is key to long term success. Call Keystone for recommendations on patterns.

Length of Cure Time

Discuss cure time with your adhesive vendor to determine the setup of your packaging line. Pressure bar time should be discussed at this time to determine how long pressure should be applied to the substrate for bonding purposes. The adhesive needs to have enough time to bite properly.

Most adhesive and glue melter issues are not due to the adhesive or melters, but are due to how the adhesive and melters are being used/misused. Many dollars can be saved by being proactive in the setup stages in choosing the correct adhesive, using the adhesive properly and maintaining a clean glue melter.

Keystone Answers Your Hot Melt Questions

Need guidance with your glue melter setup and adhesive issues? Contact a Keystone representative or call us at 800-238-8090 to get help today.

Tuesday, March 14, 2017

Leaking Glue Modules

Common Causes of Glue Module Leaks | Keystone Industries

Glue Modules: What is the Cause of My Leaks?

Being knowledgeable regarding your glue guns/modules can help in diagnosing issues. Are you having leaking, dripping, stringing or stoppage issues?

Understanding the Components of Your Glue Module

The glue applicator gun body only controls the temperature and is a go between hydraulically from the hose to the module that is mounted on the gun body.
The glue module is the valve that controls the glue flow out of the nozzle. Opening of the module is triggered either by compressed air or electricity, depending on the type of system you have. Closing of the module is controlled by either compressed air, electricity or spring.

Common Issues with Glue Modules

In order for the module to open, the needle must lift off of the seat to allow adhesive to flow. In order to close, the needle must seat firmly and completely to form a seal on the seat to stop the adhesive flow.
The needle seating process can be significantly affected by pressure, adhesive viscosity, compressed air, adhesive cleanliness or spring used to close the needle.
If adhesive is too thick, the air solenoid could have issues pushing the spring closed, therefore, preventing a tight shut off seal. Dirty air flow can cause module to open/close improperly and dirty glue can produce buildup at the seat, causing loss of a tight seal. Spring tension loss over time will eventually cause affect closing time.
Other factors that affect performance are worn seals and worn nozzles.

Talk to a Keystone Expert

Need help with a glue module issue? Contact one of our representations today or give us a call at (800)235-8090.

Tuesday, February 28, 2017

Tankless Hot Melt Systems - The Truth

The Truth About Tankless Hot Melt Systems | Keystone Industries

Before sinking an enormous amount of capital into a tankless hot-melt system, make sure you know the cons as well as the pros that the adhesive melter company is selling you. Remember, they will tell you only the good side and before you know it, you are writing a big whopping check without knowing the full picture that may affect your type of packaging application.

Why Choose Tankless Hot Melt Systems

Below are the selling points on tankless hot melt systems you will hear and what that truly means:

  • Tankless take up less space: In order to set up the temperature controls, feeders and stands, the space used is as much and sometimes more than the conventional hot melt systems. They are referencing the unit only when making this statement.
  • Less time in “Warm-up” phase: Since most packaging plants run 24 hours a day, this is not a benefit. The units are already hot from shift to shift. Also, the conventional hot melt units have a timer that can be set to heat before a shift begins.
  • Less time used in filling: Since tankless technology involves feeding small quantities of dry pellets into the heat on demand system, there are 2 factors that can come into play that can cause downtime:
    • Clog in feeding system
    • Unit runs out of glue (you cannot manually fill this system)
  • Proven & Dependable conventional melters: Melt rate times on standard melter reservoirs are 40 minutes up to 2 hours, depending on size of unit. Many people use less expensive adhesive feeders that supply these conventional units and only fill the feeders once per shift.

Using Your Current Adhesive with Tankless Systems

Did you know only certain adhesives can be used in the tankless units? You may not be able to keep your current adhesive. Not all packaging grade adhesives will blow properly in the tankless systems. Before you write that big check, make sure your specific adhesive is compatible, otherwise, you may be spending months testing glues that will work with your application.

The tankless system sounds like a great new idea, but practically, it is not for everyone. The benefit to those who are able to meet all the criteria is less char build up in the tank. With periodic preventive maintenance, which is probably already scheduled on your conventional units, control is kept on reducing any char issues in the tank. Hoses and heads have the same char issues in either scenario since they have to remain heated.

Choose Keystone for Your Tankless System Needs

Call us at (800)235-8090 or contact us online today for your melter and melter parts needs.

Tuesday, January 31, 2017

ProBlue Under Temperature Fault F2

ProBlue Under Temperature Fault F2 | Keystone Industries

Common Causes of Temperature Fault

There are a few reasons you can experience an under temperature fault on your Nordson ProBlue unit. Many people do not think about unique causes that could be causing temperature faults.

Understanding F2 Faults

ProBlue units circuity monitors the manifold temperature every 15 minutes after the "heaters" button is active. If the line voltage is low in your plant, the manifold may not reach the expected set temperature with in the 15 minute time frame set in the software. In this case, the unit will display a F2 fault.

Combating F2 Temperature Faults

There is a remedy for this situation. You can reprogram the unit to give the unit 30 minutes to heat instead of the default 15 minutes to heat.

Press and hold the "heaters" and "pump" buttons together while powering up the glue melter. During power up, the unit will display the code of Lo17O which indicates the 30 minute set time.

If you want to change the unit back to 15 minutes, repeat the process.

Solutions to Your Temperature Fault Problems

Keystone is here to help you with any temperature fault issues you might experience with hot melt equipment. We carry a range of hot melt systems to help meet your unique needs. Contact a Keystone representative for more information or call us at (800)235-8090.

Thursday, December 15, 2016

Proper Glue Hose Installation for Nordson & Other Glue Melters

Proper Glue Hose Installation for Nordson & Other Glue Melters

Improper routing and installation of a glue hose can shorten the service life. With a few simple steps, you can maximize the life of the glue hose, keep employees safe and keep your production lines running.

Proper Hose Length

For areas where hoses will be installed in a straight line, the length must be longer than the distance from port to port. As the hose is heated, the diameter increases to contain the force of the glue and the length will decrease. Some hoses have decreased in length up to 2 inches.

In this case, if the hose is too short and there isn’t enough slack, the hose fitting connections will be under stress, causing a possible leak. Even worse, a catastrophic failure of the hose breaking loose from the fitting could occur causing pressurized hot adhesive to flow.

Proper Bend Radius

Adhesive hoses are somewhat flexible, but have bend radius limitations. The hose core, fitting crimps and electrical components can be stressed to the point of failure if the hose is bent beyond the maximum recommended bend radius. Call Keystone (800-235-8090) for your hose’s specific recommended maximum bend radius.

Regarding the fitting crimps and bending near the fitting, the suggestion is to keep the hose straight for twice the hose outside diameter. If the hose OD is ½”, keep the hose “straight” beyond the metal fitting for a minimum of one inch. If this is not possible, consider using 90 degree or 45 degree elbow fittings with insulator jackets to accomplish the angle needed without stressing the hose.

Avoiding Hose Twist

Metal hose cores in a glue hose have mechanical strain limits with regards to twisting. Tighten fittings using two wrenches or “double wrenching”; one to hold the fitting from twisting and the other to tighten the hose connection. To further prevent twisting, limit bending motion of the hose to a single dimensional “plane” when routing. A hose bending only left to right, only up and down or only forward and backward is moving in a single plane. Any combination of left/right, forward/backward, and up/down movement represents 2 planes of motion and all three represent 3 planes of movement. A compound bend can occur with multiple planes of motion and this can cause the hose to twist, since the hose ends are fixed and held tight. Try to limit routing to a single plane, but, if your application requires hose movement to cross multiple planes, ask a Keystone rep for a recommendation.

Abrasion and Attachments

Another cause of premature hose failure is abrasion of the outside hose cover, exposing insulation, wiring and possibly the hose core. Live wires being exposed is a safety issue and should be avoided at all cost. Use proper hose hangers and keep moving hoses from rubbing against other surfaces. Clamps, zip ties and any other restrictive attachments should not be used on hoses since they can press on the wiring and cause hot spots. These hot spots will cause untimely hose failures and could burn through the metal hose core causing an unsafe catastrophic failure.

Contact Keystone for All Your Installation Needs

By following these simple suggestions, you can maximize the service life of your glue hoses. Call or email (sales@keystoneparts.com) Keystone with any questions or requests for recommendations.

Keystone manufactures hoses for Nordson®, Slautterback®, ITW®, HMT®, Graco®, Valco/Melton®, Klebtec® and other hot glue melters for a fraction of the cost of the OEMs. Warranty provided is equal to OEMs.