Everything you simply must know about industrial adhesives

Joining materials can be carried out in various ways; at an industrial level, welding, adhesive or mechanical connections are the typical techniques used. Joining technology is in continual development and in many different industries the use of adhesives as a joining method is becoming even more popular. In this article, we’ve compiled the must-know information about industrial adhesives.

The advantages of adhesive bonding
Industrial adhesives have been widely used in the aviation and automotive industries for a long time; just think about how the windscreen of your car is bonded. This bonding technique is also on the rise in other branches of the manufacturing industry. What are the advantages of adhesive bonding?

• You have full utilisation of the available surface
• There are no peak stresses in the bonded material
• The material does not change in shape or in structural integrity
• You achieve perfect sealing of the surface at the place of bonding
• You gain cost savings
• It’s a faster process, for rapid results
• Adhesives can also be applied as part of a hybrid system.

There are, of course, advantages and disadvantages to choosing traditional connection methods, such as bolts, nuts or welding techniques. With all these mechanical or welding connections, however, the result is immediately visible. It may also add extra weight, which can have an unfavourable impact on the product’s performance. Connections with bolts and nuts also carry the increased risk that they will loosen due to vibrations.

What should you watch out for when using adhesive bonding materials?
It is important to bear in mind when using bonding materials that each of the following factors can affect the adhesive bond: temperature, air humidity, the type of material and other external influences. Of course, patience is also vital: the curing time of the adhesive is very important for the strength of the joint.

There are lots of types of adhesives available on the market, each suited to different applications. Not all adhesives will work equally well for every material. So before you start, always check the suitability of the adhesive for the parts that need to be bonded. If in doubt, contact your Kramp account manager for specialist knowledge.

Step-by-step plan: how to ensure a good adhesive bond
Once you have found the right glue and you are ready to use it, it can be tempting to get started without the proper preparation. This can be a costly mistake, however. Our step-by-step plan for adhesive bonding will help getting the job done. Don’t forget to read the manufacturer-supplied information about the product, which might deviate from this guide!

Step 1: Cleaning the parts you are going to bond together
A good cleaner or degreaser is very important. Why is it necessary? Because there are cleaners and degreasers that leave a residue that can weaken the adhesive bond. Always make sure you have a good cleaner or degreaser, preferably one recommended by the supplier. Cleaners and degreasers that you can find with us:

• LC88365 Fast cleaner: SF 7070 Loctite 400ml, for cleaning various plastics before bonding, but can also be used for metal and other materials;
• LC149293: SF 7063 Loctite fast cleaner for cleaning all kinds of materials before bonding;
• LC1581831 FL Cleaner: a cleaner that can be used for plastic repairs and window glueing.

Step 2: Sanding and machining the parts to be bonded
In some cases, it is necessary to sand or process the materials first. By machining the surface to be bonded, the adhesive surface increases, creating a stronger bond. If you would like more information about this, please contact a Kramp product specialist.

Step 3: Cleaning the parts to be bonded – again!
If you have worked on the parts, you will need to clean the surfaces you want to glue again. 

Step 4: Glue the parts
Make sure that you spread the glue evenly and do not apply it in one place. Some adhesives have very specific instructions about ratios of the adhesive elements and quantity of glue for particular uses or materials. Always read the product manual to avoid mistakes!

Step 5: Fixing parts in the right place
Once you have applied the adhesive, bring the parts together precisely. Take your time to make sure everything is aligned properly; some adhesives are initially slippery, which can skew the connection you are trying to make.

Step 6: Note the curing time of the adhesive
We all know patience is a virtue. We all get impatient sometimes. But if you take shortcuts on adhesive curing time, it is likely that the strength of the bond will be compromised. A weak bond could lead to premature adhesive failure and disappointment at best, unnecessary expense and danger at worst.

An important note about gluing different materials
If you want to glue two different materials together, be absolutely sure that the manufacturer states that the adhesive will work with both of those materials at once. There are situations in which the material of one part will bond with the glue and the material of the other part will not, particularly if those materials react differently to certain temperatures. The adhesive bond must be able to absorb this sort of change without affecting performance.

Looking to buy adhesives?
We sell a wide range of adhesives through our webshop. And remember, if you have any technical or usage questions, you can always contact our product specialists or email knowledgecenter@kramp.com for expert guidance.