Everyone wants a safe work environment. One of the workplace hazards are explosions and fires due to static discharge, but these can be mitigated by grounding equipment. Proper grounding is the only way to ensure true static protection if you are in any environment where the potential for static discharge exists.

Many places ground with heavy duty cast clips, solid copper clips and clamps of all shapes and sizes connected to a wire and attached to drums and pipes throughout a storeroom, plant floor or pumping stations.  These are referred to as grounding assemblies or “straps.”

These areas may or may not be perfectly grounded. Even though they may look grounded, it’s hard to tell if it’s done properly. An improper ground could mean safety hazards that can lead to fire or explosions.

First and foremost, it must be determined that access to a fully grounded grounding pin or buss bar is readily available. This will be necessary for a solid true ground and will act as the backbone of the grounding system. Keep in mind, however, that the grounding pin and buss bar must be kept clean so solid metal-to-metal connections are made.

The next step in ensuring that something is properly grounded is to make sure the correct connection device is utilized.

Many times a C-clamp or center spring clip will be used for this connection. This would certainly result in a good connection as the C-clamp can bite into the metal pin or buss bar and the clamp pressure on the center spring clamp is strong enough to drive the teeth into the metal pin or bar. It’s important that the clamp or clip is able to pierce any paint that might be on the surface. The connections on the grounding pin and buss bar must be solid tight connections as maintaining continual connectivity is critical for the integrity of the entire grounding system.

The type of cabling used from connection to connection (grounding pin / buss bar to clamp or clip) will depend on the environment being grounded. If the environment is clean such as a paint mixing room, uninsulated stainless steel wire rope or braided copper can be utilized. In other applications where the environment may contain more contaminants, an insulated wire may and should be considered such as THHN (oil and gas resistant).

Now that the connection to the ground source and wire are complete, focus can be placed on the connection to the can, drum, or tank. This connection can be made with a cast clamp with points, C-clamp containing a point or center spring clip with strong clamp pressure and teeth. The type of connection depends on the type of surface in which it is being attached. If the surface is clean and free of dirt and paint, a center spring clip can work fine. The size of the clip will be determined by the size or thickness of the object being grounded. If the container is dirty or painted the connection will need to be made with a connector which will break through those layers to make a solid metal-to-metal connection. Cast clips with points and the C-clamp with a point are perfect for this application.

Once a connection is made to the first container a “daisy chain” method of connecting the remaining containers in the area can be used. This means that a grounding cable can be attached from container to container to maintain a good ground as long as the series of containers is attached to the one connected to the grounding source. Keep in mind that each grounded container must have a solid metal-to-metal connection with the grounding device. It may be necessary in more caustic environments to wire each container directly to the grounding source. This same approach can be applied to grounding pipes for fluid flow, and even grounding work stations.

Following the above steps for creating a solid grounding system should produce good results and create a safe environment.  To confirm that there is good connectivity, take resistance measurements with a multi-meter, ohm-meter or ground analyzer. To ensure entire system integrity, a lead should be placed on the connection on the grounding source (grounding pin or buss bar) and the other on the very last connection in the system. This will incorporate a resistance measurement from point-to-point for the entire grounding system. If the reading taken is zero or approaching zero, the system is well grounded and a safe environment exists. If the reading approaches 1M Ohm then check the connections throughout the system to ensure that there are solid metal-to-metal connections. Once the appropriate measurement is received (zero or approaching zero), you have a good and well-grounded system in place ensuring static protection.         

It may seem like common sense, but it’s important to make sure your grounding and bonding straps are working properly. It is essential that your clips are making a good connection. 

• Ensure your clips are clean and clear of debris.
• Check to see that you are getting a solid metal-on-metal connection. If there is paint on the surface the clips connect to, make sure the clips are breaking through that paint.
• Inspect your grounding equipment regularly and take measurements with a multimeter to ensure there is a low resistance.
• Replace any clips or straps that are too rusted to perform properly

Remember that bonding and grounding serves an important safety purpose, and regularly checking up on the grounding and bonding straps can prevent sparks and explosions.

To read more on static electricity in industry, check out our whitepaper here

If you are interested in custom-made grounding or bonding equipment, you can see our capabilities here

So you’re considering if you need a custom grounding solution for your automated paint/powder coat line, but you still have questions and concerns.  You’ve probably evaluated all your alternatives and realized it may be time to update your grounding process, and maybe you've even read our whitepaper on Static Electricity and Grounding in Industry. But there are still some questions and things to consider.  This infographic addresses the common questions and considerations that people have when evaluating grounding solutions.

 Ready to move ahead with a custom or ready-made solution for grounding to update your process? Click here and fill out the form to get the ball rolling!   

You can also read our free guides to grounding for plastic and metal painting below

When trying to determine the cause of problems encountered with electrostatic painting, it can be confusing. The problem is often solved by updating the grounding process, however this simple solution is often overlooked. 

1. There is a drop in transfer efficiency

Your measurements and output are lower than they should be. 

2. Paint thickness is not what it should be

You may see a reduced paint thickness, uneven paint thickness, or both.  

3. There is a lot of scrap/rework

Lack of a good ground can result in much higher  amounts of scrap and rework than there should be. 

4. There's more paint on the surrounding surface than on the substrate

This can indicate you had a bad ground or no ground at all. 

5. Your cost of paint has gone up

You are going through more paint to coat the same number of items. 

6. Servicing the robots doesn't help

You may have thought there was something wrong with the paint robots, but they are in working order

7. There's a drop in weight

If your substrates come out weighing less than they normally do, this can indicate that less paint is making it to the surface which usually indicates there're something wrong with the ground.

If you think updating your grounding process will help, you can head over to this handy page which addresses the most common considerations and questions for updating your grounding process. 

For more information on grounding, read our whitepaper Static Electricity and Grounding in Industry. 

You can also take a look at our free guides for grounding plastic and metal for painting.

Paint lines come in many shapes and sizes incorporating a wide range of paintable substrates. Some paint lines require large grounding assemblies to carry current while others are short light weight items used to provide a simple ground. Grounding metal is different than grounding fiberglass or plastics. The one thing in common is, everybody wants their paint line to produce high quality output with high percentages of transfer efficiency with low defects. In short, everyone wants their paint job to look great!

We all know that paint lines need too be grounded but since no line is the same where do you go to get the solid ground connection you need in the configuration your paint line will accommodate? GOOD NEWS, options exist for all grounding applications! When speaking to a supplier of grounding solutions you will need to be ready to provide the following:

•  Your paint application, what and how are you painting?
• What component of the process are you trying to improve?
  • Transfer Efficiency?
  • Output aesthetics?
  • Safety?
  • Costs?
• What grounding practices have you been using?
• What do your carriers look like?
  • Provide photos of you carriers and paint line
• What does your cleaning process entail?
• Are you looking for permanent or once and done solutions?
• Do you have a budget for the upgrade that needs to be adhered to?

With this information a potential solution can be formulated.Once an initial solution is ready a sample package is created and forwarded for testing. After enough data is collected, feedback is provided to the supplier for approval or design modifications. If modifications are required, a new sample package will be created and forwarded again for testing. This process continues until a solid grounding solution is identified and agreed upon. Once the design is approved by the paint line manager a quote will be provided based upon expected usage. A blanket order is usually the best way to keep the new grounding assemblies flowing when needed and your paint line well grounded.

Mueller Electric has been providing customer paint line grounding assemblies to paint line managers for years. Below are some of the examples of the unique custom designs that shave been created to deliver pinpoint grounding solutions for a multitude of paint environments.    
 

For more information on grounding, read our whitepaper on Static Electricity and Grounding in Industry.