What is Hermetic Sealing?

what is a hermetic seal

Hermetic sealing is the process of creating an airtight seal. Hermetic sealing can be done with plastics, epoxy resins, glass, metals, ceramics and more. There are many ways to create a hermetic seal, and even more applications. The specifics of what a hermetic seal is and what it’s for depends on the materials, applications, and processes behind it.

What is Hermetic Sealing?

A hermetic seal is simply a watertight and airtight seal. The first hermetic seal was an airtight glass tube known as the Seal of Hermes, which was used in very early alchemy. The process of hermetic sealing was named after the Greek God Hermes and the “hermetic tradition” that gave rise to alchemical experimentation. Though this first seal was made through glass, there are many ways to create an hermetic seal.

What is Hermetic Sealing Used for?

Hermetic seals have many different uses. There are many instances where contact with water or air can damage a delicate connection or stop it from working. Semiconductors, which can be damaged by contact with water or water vapor, are one of the most common. These semiconductors must be carefully sealed to keep them functioning. A hermetic seal might be created by glass, ceramic or metal to protect the semiconductor.

Nearly any device using sensitive electronics, from smartphones to advanced medical equipment to lasers and much more, uses hermetic seals. Circuits, switches, ignitors, sensors, transistors, semiconductors, microchips and much more all require the protection of a hermetic seal to function properly and maintain a long useful life. Hermetic seals are also used to protect electronics in manufacturing equipment, like hermetically sealed load cells. These load cells will maintain their accuracy, last longer, and can withstand cleaning procedures better than those that are not reliably sealed.

There are other types of hermetic seals that you see every day, but probably don’t often think about. A canned food item is an example of a hermetic seal. The can keeps food preserved by preventing contact with the air and therefore stopping bacteria from growing. Some other foods are vacuum sealed with plastic wrapping, which also prevents microbial growth.

There are other hermetic seals around your home that you might not think twice about. Lightbulbs, for example, are hermetically sealed. Many eco-friendly windows are hermetically sealed to reduce the loss of warm or cool air. Your thermostat, multiple components in your car, batteries, your TV, computer, and many other devices all use hermetic seals to function.

How to Make a Hermetic Seal

How a hermetic seal is made depends on the materials being used, and what the seal must be used for. For example, a hermetic seal made with plastic might not be ideal for a device that gets warm, while a glass hermetic seal wouldn’t make sense for a disposable item, like a ready-to-eat meal.

Glass And Metal Seals

Some hermetic seals are created simply by welding metals together. A proper weld prevents moisture and air from entering the seal. However, in some many cases, electrical signals or light still must enter or exit the seal. In these cases, a hermetically sealed glass enclosure might be ideal, or the glass might be soldered to a metal cap, depending on the needs of the object being sealed.

Glass hermetic seals can be made through matched sealed or compression seals, depending on the coefficient of thermal expansion between the metal and the glass. A matched seal is commonly used for lightbulbs, while compression seals are used for objects that must withstand more pressure fluctuations. Glass-to-metal seals can withstand temperatures up to 250 °C (compression seals) and 450°C (matched seals), so they’re useful for applications with high temperature demands. Hermetic seals can also be made using a ceramic-to-metal seal. These types of seals can withstand more demanding environments, but they are more complex to make.

Epoxy And Plastic Seals

Epoxy is another common way to create a hermetic seal. The use of epoxy again depends on the coefficient of thermal expansion between the substrate and the epoxy. Epoxy seals are commonly used in electrical devices and fiber optics. The epoxy can bond to copper, brass, or other epoxy. Epoxy seals can withstand temperatures between 70°C to +125°C or 150°C, so they’re useful for many standard applications, but can’t withstand extreme heat.

Thousands of different types of devices require hermetic sealing to keep them working properly, or to make them work at all. This airtight, waterproof seal is essential to many of the devices that we use everyday, as well as many others that are much more advanced.

9 Inefficiencies in Food Processing Eating into Money and Time

automation for FMSA compliance

Inefficiencies in your operation aren’t always big problems like a machine break-down or product contamination. Though these are certainly concerns, many sources of lost time, energy and resources—and, ultimately, lost money—are a series of small things. These small inefficiencies add up and take their toll on production time. Consider these 9 inefficiencies in food processing. How many are affecting your production line, and how much time is this costing you? Solving these seemingly small problems one by one can improve your productivity enormously in the long run.

9 Inefficiencies in Food Processing Eating Up Money and Time

1. Inaccurate measurements

Using an inaccurate weighing device is a common cause of ingredient over-use, and an inefficiency in food processing that is often overlooked. While it’s important to meet minimum amounts of any ingredient, many weighing and batching systems overfill, ultimately wasting the ingredient. Using a volumetric meter instead of a mass flow meter can create inaccuracies, as well as failing to calibrate the load cell, or damage to the load cell. If the measurement device is extremely inaccurate or inconsistent, in can cause product defects, creating more waste.

Maintaining accurate measurements is equally important for small amounts of relatively expensive ingredients and larger amounts of inexpensive ingredients. For example, overusing an ingredient by .5% might be within the tolerance, and might not seem like much for a small amount of a microingredient. However, this culminates in a .5% overuse annually, which can be substantial.

2. Energy-Wasting Equipment

Overhead costs like energy use is an easily overlooked inefficiency in food processing. As equipment ages, these costs often sneak upward without notice. A number of factors can cause equipment to waste energy. Many of these occur as the equipment ages, such as compressed air leaks from aging seals. Some can be prevented with a good maintenance schedule, such as replacing seals, and keeping proper belt tensioning and lubrication to keep from over-working motors.

Other times, this actually occurs at the equipment design stage, such as excessive horsepower on inefficient motors. When working with your equipment manufacturer, remember that more power is not necessarily a good thing; if your equipment doesn’t need the extra horsepower to run, it’s ultimately a waste.

3. Energy-Wasting Facilities

Just like equipment, facilities also age and become less energy efficient. Or, as new building materials and designs emerge, their energy rating can fall behind the norm. Inefficient heating and cooling systems, lighting, insulation, even worn-out seals on doors and windows can all create energy waste.

While a single leaky seal on a door isn’t cause for concern, it can become a problem when every door is letting cool air escape, while light fixtures are creating extra heat, and the ventilation system isn’t running properly. Besides wasting energy, this can cause both employees and machines to get overheated, reducing productivity. Over time, small issues stack up and compound. Comparing energy use over time and reassessing or making improvements can help to save thousands.

4. Ingredient Spoilage

Ingredient storage systems can have a noticeable impact on waste. First-in, first-out (FIFO) ingredient storage systems help to prevent ingredients from spoiling. However, maintaining these systems requires employee participation, training, and proper set-up. If FIFO is difficult for employees to maintain—for example, if workers must repeatedly move pallets or bulk bags, or check use dates on every shipment—the system will either introduce losses to productivity due to time, or ingredient loss due to spoilage. Taking the time to arrange an easy, manageable FIFO system, and emphasizing its importance to employees, can help to prevent this inefficiency in food processing from eating into productivity.

5. Machine Down-Time

Preventative maintenance might seem like a regular inefficiency chipping away at productivity time, however, scheduled maintenance can actually help to prevent a more costly issues; unscheduled maintenance and machine down-time. Checking lubricant levels, seals, drive tension, electrical wires, electrical sockets, load cell calibration and other preventative maintenance items regularly can help to prevent breakdowns. Scheduled maintenance means downtime is planned; the necessary tools and parts are prepared, employees aren’t unexpectedly idle, and productivity schedules aren’t lagging.

6. Excessive jogging

Excessive jogging can also cost valuable production time. Jogs occur when the automation
system stops the feeder before the target weight is achieved. The system will then start and
stop the feeder for a short duration in order to fill to the target weight. Besides creating inefficiencies in production, excessive jogging can also be hard on drive components and switchgear, because the feeder is constantly starting and stopping.

Free-fall compensation helps prevent this from happening. Two-speed operation of the feeder can also help to prevent excessive jogging.

7. Overweight Alarms

Overweight alarms occur when the batching system meters too much product into the scale. They can occur because the feeder size is not well matched to the required minimum output. They can also occur because the system stopped too early, and then had to jog to put the remainder of product into the bin. The final jog to reach the target weight can put the weight over.

Each time an overweight alarm occurs, the system halts and sends an audible and visual alarm to the operator. The operator then has the option of accepting the overweight or aborting the batch. Each alarm consumes valuable production time. The best way to prevent overweight alarms is with two-speed operation of the feeder.

Overweights can also occur because the user has an unrealistic expectation of what the system can actually weigh. Don’t set the tolerances for the system to be one scale increment if the feeders and controls are not capable of stopping the system within one increment.

8. Batch Routing

Batch destination confirmation is another inefficiency in food processing that can cost production time. When a new formula is produced prior to the discharge of the batch mixer, the operator is asked to specify the correct downstream destination for the formula. If the operator is busy doing something else, this alarm may go unnoticed for some time and cost production time.

Auto-routing is a simple automation upgrade that can solve this problem, and most automation suppliers provide it. This allows the operator to designate the bin when the formulate goes into production, thereby easily eliminating this inefficiency in production.

9. No-Flow Alarms

No-flow alarms are one of the most common and costly inefficiencies in food processing. This alarm occurs with an auto-batching system. No-flow alarms can occur when someone forgets to fill a bin, when a bin bridges or when a feeder plugs. A standard operating procedure for bin inventory and refilling bins can prevent these alarms. It may be necessary to add some type of bin agitation to the system to prevent the ingredient from hanging up in the bin or feeder.

One small inefficiency in food processing can quickly become many inefficiencies if they’re allowed to add up. Solving these small problems takes regular assessments and housekeeping, but this time is well-spent when it prevents wasted ingredients, surging energy costs, maintenance problems, and lagging productivity. Assess your operation carefully to see where you can solve these problems, and make small improvements to save time and money.

How to Choose a Food Processing Equipment Manufacturer

how to choose a food processing equipment manufacturer

When your food processing equipment works at optimal speed and efficiency, every part of your plant runs better. Choosing the right food processing equipment manufacturer is the first step to implementing the best possible equipment. Consider the following when choosing your supplier and you can reduce repairs, maintenance, and hazards.

How to Choose a Food Processing Equipment Manufacturer: 6 Considerations

1. Experience With Your Products

material segregation in batch mixing processesAll food products are unique, and each one presents unique challenges when it comes to processing. When choosing a food processing equipment manufacturer, look for experience with your products.

For example, powder or oil coatings can cause challenges in the mixing process if the equipment is not properly designed. Or, products that contain mixed nuts can experience segregation problems during batching, and require special considerations for allergies. Working with milk or other perishable liquids requires adherence to 3-A sanitary standards. A food processing equipment manufacturer who has designed equipment for your products and ingredients will be aware of these unique challenges and requirements.

2. Offers Product Testing

With product testing, you can be sure that your equipment will operate according to plan. Sometimes, unexpected problems can arise with your equipment and processes. Product testing with your food processing equipment manufacturer allows you to address these problems before they become problems at your facility.

With product testing, your equipment supplier will conduct a demonstration using your ingredients and a version of your equipment. This test will allow you to see how the process actually works, and how this compares to how it’s supposed to work.

Product testing can reveal issues that arise at any point in the process, such as inadequate mixing, inconsistent coating, cycle times that are too long or too short, inaccurate weighing, or other challenges. Then, these can be addressed before your equipment is finished and shipped.

3. Provides References

One of the best ways to choose a food processing equipment manufacturer is to take a closer look at the equipment they’ve built in the past. Your equipment manufacturer should provide a list of references, including a contact person you can ask about the equipment.

Consider the following when examining the list of references:

  • Are your ingredients, products and processes comparable?
  • Are your environments and volumes comparable? Keep in mind that changes in temperatures, humidity, and facility size can impact the equipment design.
  • Did the customer have any unexpected problems? How did the supplier respond?
  • Did the machines require repairs or maintenance? Are the parts difficult to obtain?
  • How long has the equipment been running, including both time and volume?

4. Will Customize

Food processing is not one-size-fits-all. While some standard fittings may work for your process, you should be able to customize some aspects without much trouble. You may wish to add or remove some features, add coatings or finishes, or alter the dimensions of the machine to fit your facility.

5. Complete Process Engineering

food processing system

Now more than ever before, each step in the food processing chain affects the next. For the system to perform at its highest level, each step in the process should work together. This means your food processing equipment manufacturer should have experience with every part of the process, including mixing, coating, weighing, batching, controls and more. When you choose a food processing equipment manufacturer with a range of experience, you can optimize each machine to get the most efficient mixing time, and minimal waste and maintenance.

6. Offers Plant Visits

To choose the right food processing equipment manufacturer, you may wish to inspect the manufacturer’s facility. This will give you a closer look at how the manufacturer does business, including the manufacturing equipment and technology they use, the condition of the facility, its capacity, and adherence to safety requirements. Though these details by themselves may not tell you much, all together they can show you the manufacturer’s attention to detail, level of organization, and use of technology.

When you choose the right food processing equipment manufacturer, you will not only have exceptional equipment to support a highly efficient process, but you will also have a problem-solving partner to support your equipment into the future. To learn more about food processing equipment design, manufacturing and product testing, contact us.