Posted by Chuck Keeley on | Comments Off on Open Cell vs. Closed Cell Foam: What’s the Difference?
At CGR Products, we field a lot of questions about the differences between open and closed cell foam. To address these inquiries, we’ll be comparing the two types of foam and outlining the unique benefits and properties of each.
When deciding on a material for your specific project, it’s important to understand which kind of foam will best serve your application and meet your unique requirements. The benefits of each type of foam can differ depending on your specific industry, so it’s important to fully assess each option before moving forward.
Open Cell Foam
Open cell foam is a rubber-like product made by incorporating an inflating agent, such as sodium bicarbonate, into the rubber compound; this agent gives off a gas, which expands the rubber during vulcanization.
Foam is usually classified as “open cell” when more than half of its cells are open. Common open cell materials include reticulated foam, polyurethane foam, and open cell rubber.
Some open cell foam is unique in that it operates more like a spring, easily returning to its original state after compression thanks to the unrestricted air movement and chemical makeup. Soft and breathable, open cell foam is generally more flexible and can more easily conform to sealing applications than closed cell foam. Open cell foam can also be manufactured at both high and low densities. It is less durable than closed cell options, however.
Reticulated foam is usually classified by PPI (pores per inch). 10 PPI foam would have large cell structures and allow the most flow, while 80 PPI foam would have very small cells and be more restrictive.
Closed Cell Foam
Closed cell foam is defined as a cell totally enclosed by its walls and hence not interconnecting with other cells. Closed cell foam is usually made by subjecting a rubber compound to a gas, such as nitrogen, under high pressure. This type of foam may also be made by incorporating gas-forming materials into the compound.
Closed cell foam offers a wide variety of material and density options. EPDM, neoprene, EPDM/CR/SBR, and PVC/NBR are a few common types of closed cell foams, which can range in densities from 6 lb/ft3 (soft) to 19 lb/ft3 (hard).
This type of material is ideal for sealing as it effectively reduces liquid and gas flow. Closed cell foam is also ideal for industries in which liquid resistance is critical, such as marine, HVAC, and automotive.
CGR carries several types of open and closed cell materials, including neoprene, PVC/NBR, silicone, microcellular urethane foam (PORON®), and polyurethane foam, and we keep a wide variety in stock to reduce lead times. We can also convert foam materials as needed for your application and will work with your team to find a solution that works for your project, no matter how complex.
To learn more about foam materials and identify which type is right for your next project, download our comprehensive Chemical Compatibility Guide.
Posted by Mike Burris on | Comments Off on Die Cut Solutions for EV Batteries using Avery Dennison Materials
CGR Products is your go-to converter of die cut flexible materials for Electric Vehicle (EV) Batteries. CGR Products provides solutions for thermal runaway, sealing out elements, heat shielding, gap fillers, battery cushioning, and more. CGR Products is a leading converter to solve challenges for EV battery manufacturers.
Adhesives for Compression Pads
Avery Dennison offers pressure-sensitive adhesive tapes to bond compression pad foam that protects EV Battery cells.
Individual prismatic and pouch cells in EV Battery packs need protection from impact and movement. Pouch cells can also swell during charging and discharging. To help prevent damage, EV Battery manufacturers are placing foams backed with pressure-sensitive tape between each cell.
CGR Products offers full in-house converting of these adhesives to foam. Our first step is our lamination process for adhering the adhesive to the foam. We utilize various types of laminations depending on the application including thermal transfer, infrared, and hot roll lamination.
Second, we employ the optimal die cut method to make the compression pads. For ease of installation, CGR Products can supply these pads kiss cut on rolls. Kiss cutting is performed by cutting through the part down to, but not through, the release liner. The parts would be supplied on a roll or pad for easy “peel and stick” application.
Adhesives for Gasketing
Sealing and gasketing are critical for preventing water intrusion and unwanted noise, vibration, and harshness, and protecting pack enclosures from contact with the chassis. Avery Dennison offers transfer and double-coated tapes for bonding various gasket materials, including foams and fibers.
As described above with compression pads, CGR Products has complete in-house capabilities to laminate the adhesives and die cut the finished gaskets. We have extensive experience with laminating transfer and double coated tapes to various gasketing materials. The die cut gaskets can be supplied bulk packed in a box or kiss cut on rolls. Our team can help you with your gasketing project to ensure you get the easiest method for installation.
Adhesives for Thermal Management
EV and battery manufacturers have strict requirements against thermal runaway events and rely on mica, ceramic fibers, and other materials for protecting cells and passengers. Avery Dennison offers a variety of solutions for bonding these materials to cells, modules, and pack structures.
CGR Products offers lamination and die cut capabilities for these thermal management materials laminated with adhesive. These materials can be laminated with a double coat or transfer tape to help maintain the dielectric strength.
Avery Dennison EV Battery Portfolio includes a wide range of available bonding and protection tapes, built on multiple pressure-sensitive adhesive technologies. These are engineered to make EV batteries safer, more efficient, and easier to assemble. To learn more about Avery Dennison EV Battery Tape Solutions click Here
CGR Products will work with you during the early stages of your project to high level production volumes. We have a vast network of preferred suppliers and manufacturers with expert advice in making the right material selection. We have 4 locations in the USA with over 190,000 sq ft of manufacturing space and are premier converters of foams, films, rubber, insulation, lamination, and more.
Feel free to contact us today about your upcoming EV Battery die cut applications.
Posted by Chuck Keeley on | Comments Off on Interesting Times
I have been working in the converting business since 1985 and I have never seen so many external inputs converge on the industrial sector at one time and hope I never do again. It has made business planning and proactive activities, let’s just say, exciting.
Covid-19 – Pandemics are obviously rare so planning for that is an adventure all by itself. The last major pandemic was the Spanish flu in 1918 so no one alive today could help us learn from that experience. That said, the world is a very different place today with many more people and a lot more travel so what was learned during the Spanish flu would not have been that helpful anyway. And it wasn’t. The high level of social conflict that we are currently experiencing hasn’t helped either. I hope that goes away soon.
Supply Chain Disruptions – The drastic slowdown caused by the pandemic and the subsequent flood of demand that has occurred as the pandemic has waned has created shortages in a wide range of raw materials. We have seen specific raw material shortages in the past, but the breadth of the recent shortages has been shocking. I have participated in many meetings with both customers and suppliers that I would have never gotten involved with in the past. It is amazing how much time and energy this has required out of so many of our associates.
Inflation – We have had periods of inflation to match this current time, but they are rare and happened a long time ago. The 1970’s were comparable to today, but that was before my 35 years in the business. I was in high school and my experience with inflation at that time was waiting in line to get gas for my 1972 Toyota Corolla. We supply lots of sku’s to lots of customers, so this pricing pressure has also created an incredible amount of extra work for the associates in our company.
Finding Personnel – This has happened for several reasons, but mainly because of the high number of people that decided to retire due to Covid 19. The tenure at our company is outstanding and has helped us weather this storm, but when we have had to find new people, it has been difficult. You can tell people that you have a good company culture, but until a person gets to experience it, they really don’t know. Furthermore, every company is going to say that.
Recession Concerns – There has been a lot of talk about a coming recession. Any election will ramp up and potentially exaggerate that kind of talk and the recent election was no different. We have experienced some slowness in certain segments, but not companywide. It will be interesting to see how this unfolds.
I am not sure when or if this convergence of inputs will ever happen in the future. And frankly, I am not sure it has ever happened in the history of this country. These inputs have made decision making interesting to say the least. Some of these events are exact opposites. Planning for a business slowdown or recession and struggling to find people to hire at the same time makes no sense. We have done more reacting to events than planning and being proactive in the last two years than we ever have. It has not been our normal way to operate and has caused undue stress for everyone on our team.
We recently tabulated our engagement survey results and I am thrilled that we have maintained the high levels that we have experienced in the past. We use the Gallup 12 question engagement survey that has been around for a long time. We use this data to see how we compare to other companies and to see if our trends over time are performing adequately. Do we have some areas that bare watching, yes, but overall, we feel very good about where we are. The burdens on our associates in all departments has been very high due to all the external inputs I mentioned above. As we all know our associates are our most important asset, so navigating the extra stress is critical. It requires good communication from the department heads especially due to the combination of working on site and off site.
The past couple of years have created issues that call for difficult conversations with customers and suppliers. It has also created opportunities for success. Challenges can turn into successes when we effectively partner with our customers and suppliers. I think the title of this article, Interesting Times, sums up the last two years. It will be interesting to see what the future holds. Have a fabulous holiday season.
For most major car makers, all parts must be made from materials that are on their approved source list. It’s a competitive business and only the best suppliers with a proven track record of quality, new technology, on-time delivery and service will make the cut. Once a material has been included on the approved source list or our fabricator partners have been selected as preferred suppliers, the task is not over. We must continually maintain or improve our specs to stay competitive and meet the high expectations of auto makers and their supply chain.
Armacell’s foam is used in automotive components such as gaskets for sealing out water, air, dust or noise.
FIAT CHRYSLER AUTOMOBILES
In the 1930’s Chrysler was known for its iconic Chrysler building in New York City and affordable luxury vehicles. Now they are known as a maker of family cars including a hybrid. Armacell makes a number of materials on the approved source list for FCA including Monarch 3091® and EnsoLite® EF0 which meet the MSAY 430 spec. Both have the necessary resistance to UV, weathering and acid. They meet the horizontal burn requirements for interior automotive gaskets. EnsoLite EF0 has the added benefit of being a super soft and conformable, semi-closed cell, crushed foam that works well in applications that require the material to spring back to its original thickness.
Armacell made more than 6 million square feet of EnsoLite SF0 in 2018
TOYOTA MOTOR CORP
For 75 years, Toyota has disrupted the market and revolutionized manufacturing. As a maker of cars that are known for efficiency and reliability, Toyota stands by their brand. It makes sense that they insist on suppliers that do the same. Armacell makes a number of products that meet the tough Toyota TSM 1501G spec for automobile parts. Monarch 8002 is a 100% EPDM bun that has a dependable resistance to corrosive acids, UV and weathering. That means the material will hold up to the abuse auto parts take over time. EnsoLite IG1, manufactured in continuous rolls or sheets, has excellent resistance to oil, fuel and flame. These qualities make EnsoLite and Monarch great choices for gaskets and seals in automotive design.
Click Here to Download the Full Automotive Component Foams PDF.
To learn more about Armacell Products, visit their website – Armacell
To go along with the Component foams, Avery Dennison has put together an in-depth adhesive bonding study which can be found Here.
As flexible material specialists, the CGR Products team offers years of experience in converting foam material into gaskets and components. Our in-house precision cutting services include rotary and flatbed die cutting, kiss cutting, slitting, splitting, knife cutting, and more. For your next foam project, Contact Us today.
Posted by Mike Burris on | Comments Off on How to Prepare for Your Next Adhesive Materials Project
Adhesive bonding is often required for projects in many applications and industries.
With various types of bonds available to meet virtually any need, it’s important to know how to pinpoint the best option for your unique project. When discussing your application with a bonding products manufacturer, you will be presented with a series of questions in order to narrow down adhesive options. Being able to anticipate these preliminary questions and having a clear understanding of your needs will help ensure that your project runs as smoothly and cost efficiently as possible. (more…)
Posted by Chuck Keeley on | Comments Off on Why is Being “Wrong” so Important?
Let’s face it, nobody likes to be wrong about anything. It challenges your sense of self confidence, it’s embarrassing, and it just doesn’t feel good.
That said, being wrong is where learning takes place. When people are correct, they move to the next thing. There is no need for reflection or thinking. Being wrong forces people to contemplate their position and how they arrived at their decision. In doing this people see things differently and learn how to make better decisions. That part of being wrong is obvious, but there is much more to it.
The impact on human interactions when people are wrong is monumental. Almost anyone that realizes they are wrong becomes defensive. In that moment communication can deteriorate and in many cases that makes reaching a resolution difficult, if not impossible. On the other hand, when someone needs to point out that another person is incorrect for some reason, it likely causes anxiety for the person that needs to explain why. In a team structure, it can create stress and make it difficult for the team to function at a high level. We have all experienced situations where people go to great lengths to “prove” they are correct. There are two reasons people decide to press their position; they believe they are correct, or they do not want to lose. Regardless of the reason, this activity is usually destructive for your relationships and your ability to function effectively in your role. No matter which reason is behind pushing that you are correct, at that moment pressing ahead is not going to help resolve anything. When there is disagreement, it is best to do nothing more than listen.
So, what are the not so obvious reasons why it is important to be wrong and accept it gracefully? Other people will analyze how you react to being wrong and how they interpret that will go a long way to determine what they think of you. When you accept that you are incorrect professionally, that shows them that you have confidence in yourself. At that moment they become more confident in you. At the same time, it makes it much easier for people to interact with you. They are not afraid to point out your inaccuracies. In other words, you have given them permission to challenge you. People will be more candid and that will create more fruitful conversations and better decisions in your relationships and in team environments.
Picking your Battles
Let me take this to another level and suggest that at times you should go out of your way to say you are wrong even when you are not. I know that sounds strange but hear me out. You need to decide if you gain more by “not being right”. Human emotions are a powerful thing and in many cases winning the emotional war is more important than winning the immediate battle on an issue or topic. There are many interactions where it simply does not matter who is right. If someone thinks a car is gray and I think it’s silver, does it matter at all who is correct? For that matter, whether a car is blue or red doesn’t matter. As you know this is called picking your battles. Furthermore, if there is more than one way to solve a problem, it can be better in the long run to “not be right”, or probably more accurately, not insisting to do it your way, even if their way is not as good as yours in your opinion. It helps people learn to solve problems and it makes them feel good which is a positive for everyone involved. No matter what role you are in, a spouse, a colleague, or a leader, productive resolutions to important issues are critical. Being right or doing things your way in many cases will do nothing to solve problems because of the “collateral” damage that can occur.
Now you are asking, did Chuck really write this? Okay, do as I say, not as I do. I realize that this is a struggle for me and possibly others, but I hope you will at least give me credit for acknowledging that and putting this on paper (or on the computer screen).
Finally, I want to thank all our constituents, our wonderful Associates, our paying Customers, and our Supplier partners. It has been a trying year in many ways, but it is years like this that make us appreciate the not so trying years. Have a safe and enjoyable holiday season.
Posted by Mike Burris on | Comments Off on Ingress Protection for Electrical Enclosures
Since CGR Products’ founding in 1963, we’ve worked with design engineers to bring projects to life, and we do everything we can to make that process efficient, affordable and successful. CGR uses a wide variety of converting methods and equipment to create parts and designs with precision and efficiency
Enclosure gaskets are mechanical parts used to provide weatherproof seals on electrical enclosures and its doors. The typical method of attaching the gaskets is by means of a chemical fastener such as pressure sensitive adhesives (PSA). The mating surfaces many times can be irregular. In order to protect the sensitive electronic equipment inside the enclosure, a properly selected and manufactured gasket is critical. The enclosures can be used indoors or outdoors; therefore, a properly selected material and design are essential to ensure proper performance and long life. Generally, gaskets are used to seal out dust, dirt, water, Electromagnetic Interference (EMI), and Radio Frequency (RFI). Gaskets can also be used to dissipate vibration.
Water: Direct spray tests are conducted. These tests can be a drip test, pressure hose test, or submersion test. UL requires that no water enter the unit during any of these tests. Full submersion tests can require up to 24 hours of submersion with zero entry of moisture. Oil Swell: The gasket material is submerged in oil for 24 hours. The gasket material cannot swell over 25% of its original dimension or shrink more than 1%. Tensile & Elongation: Some NEMA tests require tensile and elongation retention. For tensile and elongation the gasket materials are aged for 1 week @ 70 degrees C (158 F). After completion, the new and aged gasket materials are compared. To pass the tensile test the aged gasket material must stretch 75% of the same length as the new material before breaking. Elongation requires that the amount of force needed to break the aged material must be at least 75% of the new material. Other tests include water absorption, compression deflection, and compression set. Contact CGR Products for a more detailed explanation for all of these industry tests.
For a FREE downloadable PDF version to keep for your records:
Die Cut Gaskets: Die cutting is the general process of using a die or tooling to shear webs of low-strength materials, such as rubber, fiber, foam, paper, paper, plastics, thin metals, and pressure-sensitive adhesive tapes.
Die cutting can produce a precise shape with no seams. These gaskets form around the entire perimeter of the enclosure or the sealing surface. These type of gaskets can be supplied individually, in sheets, kiss-cut on rolls, or in strips, with or without pressure sensitive adhesives for mounting.
Strip Gasketing: This method is the oldest. Supplied in rolls, the manufacturers of the enclosures adhere strips of the gasket material to the enclosure surface to be sealed. One side of the gasket material will have a pressure sensitive adhesive designed to adhere to the enclosure structure. The corners are not sealed due to the strip design. This method is the most economical but the corners are areas of concern for some applications.
Fold- out / Dovetail Gasket In instances of very large enclosures, high volumes, or the design does not allow for strip gaskets, a fold-out or dovetail gasket may be an option. The fold-out gasket allows the die cut to be expanded to its final shape, eliminating the center scrap. A dovetail gasket works in a similar fashion, except the corners are mitered and fit together comparable to a jigsaw puzzle. The design of the enclosure and level of ingress protection needed will determine if this type of gasket is suitable.
Elastomeric materials are the most common and affordable materials used for enclosure gaskets and seals. These materials are available in foams, sponge, foam blends, and cork blends, with and without pressure sensitive adhesives. The key to choosing a gasket material is defining the environment in which it must perform. One must consider temperature / thermal management requirements, UV and Ozone exposure, EMI / RFI resistance, just to name a few.
What can CGR Products do for you? CGR Products can assist in suggesting a material for an electrical enclosure. We have worked with many enclosure manufactures over the last 50 years. The full CGR Resource Library and team of experts are available to clients with specifications, cost charts, comparative material information and more. Our design team works with automotive, marine, appliance, plastic molding, power tool, electrical, small engine and countless other clients.
Our in-house tool and die capabilities mean maximum problem solving with minimal lead times, and an extensive inventory of raw materials supports projects of all kinds. Safety stocks are in place with our inventory of raw materials, and consultation with our experienced staff is always available to get you started.
For a FREE downloadable PDF version to keep for your records:
Consider CGR Products when you are developing your enclosure protection. With over 170,000 square feet of manufacturing and warehouse space and over 100 top-quality machines, CGR serves a diverse range of clients, including those in the electrical enclosure industry.
To request a quote for your next gasket click Here or visit our Sample Gallery to view a portfolio encompassing all the industries we serve.
Posted by Mike Burris on | Comments Off on Learn About CGR Products Laminating Services
At CGR Products, we laminate many different materials on a daily basis. We can laminate materials up to 84″ wide and as thin as .062″. Materials can range from closed cell foam to heavy fabrics. In this series, we will look at some common ways CGR Products offers laminating services.
Heat Platen Laminating
This type lamination involves a process where the adhesive roll rides over a heated platen. Heat is used to soften the adhesive which is typically called “Flow”. The heat of the platen is computer controlled and is critical to the speed of the process. The material being laminated is pulled through the machine via driven rollers and the adhesive is applied to the bottom side of the substrate. The bond of adhesive to the substrate is performed at the nip roller. Once bonded the materials can be rewound and supplied on a core.
Infrared laminating is similar to heat platen laminating other than the heat source. This process uses Infrared heat to help the adhesive flow before it is applied to the material. One benefit of infrared is the heat can be micro adjusted while in process which allows the operator to quickly find the optimum temperature to create the best bond. The infrared process is instant so the heat can be started and stopped within seconds saving valuable time and material.
Camouflage fabric laminated to closed cell sponge rubber
Hot Roll Laminating
Hot Roll lamination involves applying adhesive over a heated drum. The heated drum helps the adhesive flow just before being applied to the substrate. CGR Products hot roll laminator will handle materials up to 84″ wide. Our hot roll laminator is well suited for materials such as carpet and textiles. A common use for this machine is the process of glue web lamination. This process allows customers to reactivate the adhesive with heat when parts are ready to be installed.
For high volume die cutting applications, we utilize Rotary lamination. We commonly laminate materials up to 16″ wide such as 3M VHB, Copper foils, and Mylar. Depending on the complexity of the part, we can usually laminate and cut the part in one pass. This helps to reduce cost and increase responsiveness to your customer.
To learn more about our lamination capabilities, visit our laminating services page. Feel free to click around our website or visit our Sample Gallery to view a portfolio encompassing many of the industries we serve.
Posted by Mike Burris on | Comments Off on Gap Fillers for Acoustical and Ingress Protection
Elastomeric gap fillers come in many shapes and sizes, from open cell foam used for acoustical management, to closed cell sponge used for sealing outside elements. In this article, we will discuss three types of gap fillers that CGR Products manufactures on a daily basis.
Open Cell Polyurethane
Open cell polyurethane is a great low cost material as a gap filler when sealing out water is not applicable. Open cell foam is made up of cells that are intentionally left open, which results in foam that is softer and more flexible. Its composition allows air and moisture to pass through so that when condensation takes place, the foam dries and doesn’t hold the moisture.
Open cell polyurethane works well for items such as bulldozers, excavators, generators, and other heavy equipment thathave engines that generate a significant amount of noise. Polyurethane foam gap fillers can help reduce engine noise and other acoustical noises when water ingress is not an issue.
Open cell polyurethane from CGR Products is available with or without adhesive on one side. This material can be die cut into any shape used for a specific area or supplied in roll form. Thickness typically ranges from .125″ to 1.25″. We utilize an acrylic adhesive on our polyurethane foam for optimal long-term, durable applications.
Closed Cell Foam
Closed cell foam is made of cells that are fully closed and packed tightly together. This results in foam that is more rigid and stable than open cell foam. Closed cell foam can block air movement and water ingress. Due to the cell composition, closed cell foam is typically much denser than open cell foam.
Closed cell foam rubber can fill large voids and gaps, and also has cushioning properties to help lessen impact between two substrates. Closed cell foam is perfect for sealing gaps and helps reduce ingress, whereas open cell foam offers more flexibility. Additionally, closed cell foam is ideal for outdoor applications because it resists weathering, UV rays, and fungi.
At CGR Products, we offer a variety of adhesive options for closed cell foam gap fillers. From economical “aid in assembly” applications to higher performance permanent bonding applications. We can die cut these fillers into individual parts or they can be supplied in continuous rolls. We skive our thickness in house to accommodate our customers exact specifications.
Crushed Semi-Closed Cell Foam
Crushed semi-closed foam is great for filling uneven gaps and sealing out acoustics, dust, heat, and air. Semi-closed cell foam is a soft, flexible foam. It has good UV resistance and good resistance to ozone and weathering, making it an ideal material for both indoor and outdoor use. This soft, compressible closed-cell foam, can fill various types of gaps, impede heat, water, sound, and vibration, offering a solution for various uneven types of gap filler applications. Semi-closed cell materials combine the flexibility of open cell materials with the excellent sealing capabilities of closed cell foams.
As with our closed cell foams, CGR Products offer a variety of adhesive options for semi-closed cell foam gap fillers. We offer die cutting, and various types of fabrication, such as layering and bonding different types of foams. An example of a layered gap filler is a closed cell foam on the bottom for rigidity and support, bonded with a crushed foam on the top for compression and uneven surfaces. Crushed semi-closed cell gap fillers can be die cut to meet specific sizes or supplied in roll form.
Consider CGR Products when you are developing gap fillers for sound and ingress protection. With over 170,000 square feet of manufacturing and warehouse space and over 100 top-quality machines, CGR serves a diverse range of clients, including those in the heavy equipment industry. To learn more about our capabilities visit our Die Cutting pages or visit our Open and Closed Cell Foam pages to view a portfolio of the different types of foam we work with.
Posted by Mike Burris on | Comments Off on Noise, Vibration, and Harshness (NVH): What You Need to Know
Guest Author: Technicon Acoustics
Noise, Vibration, and Harshness (NVH) is a concern for many companies. One of our long time suppliers Technicon Acoustics has provided the below resource and also has a full version pdf available to download here.
The extraneous sound and vibration are more than just an annoyance for people who work around noisy machinery.Excess equipmentnoise creates a perception of low quality that can decrease the perceived value of an OEM’s product. Noise and vibration are first and foremost bothersome, but it can also cause underlying issues of increased wear and tear, ultimately leading to shorter equipment life. These results havedetrimental effects on the marketability of the product, decreasingits appeal to the customer.
Fortunately, there are methods to decrease excessive noise and vibration tooptimize performance and enhance the overall consensus of your product.
What is the Meaning of NVH?
NVH stands for “Noise, Vibration, and Harshness.” NVH seeks to understand the source of industrial noise and modify equipment to reduce it. When looking for methods to diminish the noise and vibration from machinery, Technicon Acoustics relies on these core principles when engaging in equipment modification:
Reducing the source strength
Interrupting the path of the noise and vibration
Absorbing the noise and vibration
Smoothing out sound quality and annoying tones
Increasing speech intelligibility inside of the machinery
Sound waves move outward from their source at different strengths and speeds, depending upon the mediums they encounter. Installing the right kind of barrier material deflects sound waves, reducing their impact. Some mediums absorb sound waves rather than allowing them to proliferate. Specialized foams are often used to absorb sound waves caused by vibrations.
The field of NVH has its roots in the automotive industry. Sound dampening methods were originally developed to reduce the noise produced by automobiles, but now noise and vibration control techniques are applied across an array of industries.
Engines and motors on machines and vehicles are the primary sources of noise in an industrial setting. Interrupting the path of the noise involves installing barriers within the machinery, as well as equipping individual components that are prone to vibration with damping material that reduces vibrations.By addressing both structure-borne and airborne noise the overall sound quality of the machinery improves. In turn, this improves the ability of operators or passengers to understand one another or to hear the speech from a GPS or radio. This is the definition of speech intelligibility.
Increasing Sound Quality and Speech Intelligibility
Not all sound is created equal. The different sounds and their harshness all have a unique perception to the individual. Some noises may sound alike, but have certain attributes which make it more disturbing. A tone is defined as any frequency bin that has a dB rating of +/- 3dB from the previous bin, which makes the difference audible and annoying to the human ear. There are methods to reduce noise and vibration, butmasking the harshness of the noise needs to be accounted for as well.
By properly addressing the noise sources, the acoustic signature becomes less harsh. No one wants to be in or around a piece of equipment that has a loud annoying tone to it – whining, thumping, scraping, etc. Improving the sound quality of a machine and smoothing outthe annoying tones helps improve speech intelligibility, which is vital inside cabs orsimply being around the equipment.
In an ever-growing world of digital communication,speech intelligibility is not just important for person–to–person interaction. Devices also need to be able to understand voice commands that are given by the operators and vice versa.
Why is Measuring NVH Important?
Measuring NVH and implementing the correct acoustic solutions will enhance the value of your product. Customers commonly look for the equipment and machinery that check all the boxes on their shortlist, which always includes a product with the least amount of excessive noise, vibration, and harshness.
With vehicles, noise originates in the powertrain, which includes the motor, engine, exhaust, and all ancillary support systems. At lower speeds, powertrain noise is the most noticeable type of sound. At higher speeds—those exceeding 100 km per hour—rolling noise takes over. Rolling noise is directly tied to airflow. An everyday example of this would be to compare the noise generated by a car in city traffic compared with the noise generated on the highway.
Vibration is caused by the sound waves generated by moving components within the equipment or vehicle. As sound waves emanate from their source, they reverberate off of other components and cause them to vibrate as well.
When it comes to perceptible sound, the human ear has a wide range. We are able to sense anywhere between 20-20,000 Hz. It is critical for engineers and manufacturers to reduce the upper threshold of their equipment’s NVH sources during the design process to appropriately mitigate risks posed by industrial noise.
Lowering NVH Levels with Technicon Acoustics
When dealing with sources of NVH, there are two types of sounds that need to be considered:
Structure-borne sound results from all moving components within the machinery. Airborne sound is generated by the equipment’s aerodynamics and combustion processes and is transmitted directly to your ear. Together, these two types of sound compose the machinery’s overall acoustics.
Technicon Acoustics uses different solutions to reduce harmfulnoise. Designed to address the three core NVH principles, these solutions include:
Acoustic absorbers are made using porous materials like polyester foam and polyester fiber. These absorbers are installed on sound-reflective surfaces to prevent airborne noise from proliferating and affecting equipment operators and bystanders.
Acoustic barriers are made from mass–loaded vinyl, a dense material that stops sound waves from spreading. Barriers serve as an environmental modification and are often installed on surfaces surrounding industrial machinery or in the cab of a vehicle.
Certain materials actually amplify the frequency and harshness of sound waves. Damping materials such as PVC and foam composites dissipate sound waves before they amplify and are used to keep the interiors of large-scale mass transit vehicles comfortable for passengers.
Click here to download the full NVH materials guide PDF.
CGR Products has worked with Technicon foams for well over 30 years, providing solutions ranging from small gap fillers to full enclosure panels. As flexible material specialists, the CGR Products team offers years of experience in converting foam materials into gaskets and components. Our in-house precision cutting services include rotary, flatbed, kiss cutting, slitting, waterjet, knife cutting, and more.