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Interface Submersible Load Cells

Interface load cells and force measurement devices are designed for all types of environments. Providing solutions to those working in and serving the maritime industry Interface offers products engineered to provide accurate and reliable measurement data near shore, offshore and underwater.

Interface offers a variety of force measurement products that are designed for harsh environments and submersible use cases, both for single tests as well as designed into components and manufactured goods. Often these products are used for continuous regulatory and safety monitoring applications.

Interface submersible load cells and specialized sensors can transmit data through underwater applications and harsh weather conditions. These load cells can survive through underwater submersions at different capacities, and relay information to surface level or underwater devices. Interface load cells are used to regulate harsh maritime situations such as underwater tension lines, underwater drilling, as well as for storm and tsunami monitoring.

Submersible load cells are available in a range of capacities and configurations, from miniature load cells to load shackles. Interface provides standard submersible products as well as custom solutions that are designed to the exact specification. We also provide instrumentation solutions that can be fully sealed with wireless components. Working with our expert engineers, we can provide waterproof housing of sensors, including for our line of LowProfile Load Cells and Interface Multi-Axis Sensors to be used in harsh environments and underwater.

An example of a submersible product is the Interface WMC Sealed Stainless Steel Miniature Load Cell. This is an environmentally sealed tension and compression load cell useful for rugged conditions. The stainless steel construction and small size provide many benefits when using for underwater applications.  This model is available in capacities ranging from 5 to 500 lbf (22 to 2200 N) and utilizes Interface’s proprietary temperature compensated strain gages for precision measurement applications.

Another example of a submersible product is the Interface ISHK-B Load Shackle. It is designed for lifting and weighing in rugged or harsh environments, including submersible applications. The shackle pin is forged from high tensile stainless steel and high tensile carbon steel. Every load shackle is machined to exact specifications. The ISHK-B is internally gaged and the whole instrumented area is sealed to IP67 to protect it in service. The WTSSHK-B is the wireless version.

So, how do we guarantee accurate results even when these products are submerged or splashed? It’s all in the design, similar to the way new iPhones are made to be waterproof, our load cells can be designed to remain water-tight and accurate at a variety of depths. All electronic components are sealed so that data can be recorded and transmitted via waterproof cables or wirelessly.

Below are two examples of real applications that required Interface’s submersible load cell solutions.

Hydrofoil Testing In Wave Tank

Hydrofoil design is a delicate balance between performance and complexity. Finding the right shape without using overly complex angles to achieve the desired amount of lift is crucial when designing a successful hydrofoil. Once an engineer’s concepts are ready for testing, the best force measurement equipment is required to sense the subtle differences between hydrofoil designs. Lift and drag are the most important characteristics of a hydrofoil. The 3A120 3-Axis Force Load Cell is needed to read these forces. The Fz senses lift and the Fx and Fy sense the drag. The 3-Axis Force Load Cell and bridge amplifier are protected in a waterproof housing. The watercraft is placed in a wave tank or current simulator. Using the BSC4D-USB bridge amplifier increases the visibility of the load cells output signals. When using the load cell and bridge amplifier, the engineers can record the real-world lift and drag forces the hydrofoils apply to on the watercraft. This data allows a more in-depth comparison of proposed hydrofoil designs to find the best model for the job. Read more about this solution here.

Mooring Line TensionMooring Line Tension Testing

Due to the changing weather conditions, mooring cable lines undergo wear and tear. A customer wanted to ensure all mooring lines for ships or vessels are securely loaded at the same tension, so that they do not risk the mooring lines breaking or causing damage. Interface’s WTSTL Wireless Tension Link Load Cells can be attached to each mooring cable while in use. Results are sent to the customers through the WTS-BS-4 USB Industrial Base Station when connected to the customer’s supplied PC computer/Laptop. Data can also be transmitted to the WTS-BS-1-HA Handheld Display for Multiple Transmitters, giving the customer the option to view multiple mooring cable line tensions. Using this solution, the customer was able to verify the tension on multiple mooring cable lines. Thus, resulting in their ship being safely docked and secure. Read more here.

Interface expert engineers can help you design customizable solutions for all types of applications using our products designed for offshore, underwater, and splash zone locations.

Here are a few more examples of products we provide to the maritime industry.

Additional Resources

Maritime Measurement Solutions for Onshore and Submersible Applications

Deeper Dive into Maritime Solutions from Interface

CASE STUDY: Serving the Maritime Industry

Maritime Brochure

Interface Explores Maritime Applications Near and Offshore

 

Maritime Measurement Solutions for Onshore and Submersible Applications

Maritime test and measurement applications are some of the most unique because they require specially designed equipment that can handle the often-harsh environments in testing and during ongoing operational use.

The solutions for the maritime industry require technologies that measure force, torque, and weight under extreme and uncommon conditions. Interface provides products that have been used for withstanding the rigorous requirements of monitoring underwater tension lines, seaborne components and material testing, boat and ship engine testing, equipment durability and safety regulation monitoring, lift capacity measurements, energy extraction equipment, and storm and tsunami monitoring.

We have been a long-time supplier of sensor technologies and instrumentation that are applied in building and maintaining boats, yachts, and other water vessels of all sizes. Our force measurement solutions are used for waterborne vessels, maintenance, safety equipment, and offshore products. You can learn more in our maritime case study here.

Interface offers a wide variety of submersible and wireless load cells, DAQ and instrumentation products, and rugged load shackles, load pins and tension links. Maritime manufacturers and field users rely on these quality products as they are designed for test and measurement requirements onshore, near-shore, and completely undersea.

Interface Maritime Capabilities and Solutions:

  • Stainless steel and rugged load cell designs for different temperatures and climates
  • Environmentally sealed products used in harsh environments
  • Wireless telemetry system components
  • Custom solutions based on safety and regulatory specifications
  • OEM engineered products for submersible use cases
  • Bluetooth and Wireless data acquisition and instrumentation for safety monitoring
  • Load pins and load shackles for continuous hoist and lifting applications

Mooring Line Tension

Included below are a few examples of applications our products are used for testing, force measurement, performance monitoring, regulatory and equipment maintenance:

  • Weight and tension monitor
  • Motor and engine testing
  • Submersible equipment tests
  • Commercial fishing wire rope testing
  • Hydrofoil testing in wave tank
  • Crane block safety check
  • Mooring tension testing and quick release hooks (QRH)
  • Crane capacity verification and force regulation
  • WTS yacht rigging inspection
  • Defense submergible tests

Interface understands that the maritime industry has high standards and requirements force and torque testing, measurement, and weighing.  Accuracy in testing is absolutely critical. Interface’s quality measurement solutions provide accurate data needed for all types of maritime equipment used to ensure safety and success. Our Interface expert engineers can help you design customizable solutions for all types of applications using our products designed for offshore, underwater, and splash zone locations.

This is just a preview of our capabilities in the maritime industry. To learn more, check out our maritime solutions. We also recently developed a new maritime solutions brochure, which provides in-depth information on our submersible product offerings, as well as other ruggedized products for maritime applications.

Maritime-Brochure

Tension Links 101

A tension link load cell is commonly used in lifting, both for short and long distances, and weighing applications. This type of load cell sensor generally has capacities ranging from 2.2K lbf to 1.1M lbf (5 to 500 metric tons). All tension links are available in custom versions and large capacities based on the customer’s project requirements.

Interface’s Tension Link series is manufactured from high tensile aluminum and stainless steel. Matched to shackle sizes, the load links have a rugged design for uses in harsh environments on the surface and in water. The tension links are environmentally sealed to IP65, IP66 or IP67. There are higher ratings available upon request.

A major benefit of Interface tension links is the option for custom designs in dimensions, ratings and capacities. The tension links are easy to install and are highly accurate.  They are compact in size and light weight. Another benefit is the options available, which include standard, wireless and self-indicating, giving the operator a variety of application use cases for quick measurement readings.  Self-indicating tension links have a built-inaudible alarm, which can be set by the operator to warn when an applied weight or force is met.

Often, customers will integrate the tension links with an Interface Crosby styled load shackle for robust applications that require accurate and reliable force measurement used for lifting, weighing, hoisting or towing apparatus that need sensors for safety and monitoring.

Wireless options are growing in acceptance for all types of uses. Interface provides wireless tension links that are compact and reduce the overall product weight based on the casing used to house the small alkaline batteries, which can be easily accessed by removing the telemetry housing cover while the internal electronics remain completely sealed. The antenna is also internally mounted, protecting it from accidental damage during use and handling, which is ideal for harsh environments.

Watch this discussion to learn more about the wireless features of the Interface Tension Links and Load Shackles.

Interface’s most popular tension links include:

WTSTL Wireless Tension Link Load CellDesigned for lifting applications requiring short or long distances. This product can transmit wirelessly up to 600 meters in distance (clear line of sight) to a handheld display or USB base station. Model WTSTL is available in capacities ranging from 11K lbf to 220K lbf (5 to 100 metric tons). Custom versions and larger capacities are available upon request.

ISITL Self-Indicating Tension Link Load CellManufactured from high tensile aluminum to minimize weight, the ISITL is great for lifting and weighing in rugged or harsh environments.  The self-indication tension link load cell is ideal for mobile use cases.  It is simple to install and is matched to standard shackle sizes. They have a built-in display for applied weight or force in tons, kgs, lbs or kN. Interface can also offer a custom software to meet any specific application requirements for digital display or readouts.

ITL Tension Link Load Cell – This basic tension link can be amplified with 5VDC, 10VDC or 4-20mA Outputs. It can also be made to meet ATEX requirements. Model ITL is available in capacities ranging from 11K lbf to 220K lbf (5 to 100 metric tons). Custom versions and larger capacities can be requested at no additional charge, based on the exact specifications needed by the customer.

To learn more about our wide variety of load pins, load shackles and tension links, please visit www.interfaceforce.com/product-category/load-pins-tension-links-and-load-shackles/.

 

 

Understanding One-Cell Force Measurement Systems

When it comes to load cells and force measurement systems used to test and validate product designs, the options for different configurations is nearly endless. In fact, Interface has tens of thousands of force measurement products in standard, modified and custom-made configurations.

In our recent post, Considerations for Steel, Stainless Steel and Aluminum Load Cells, we detailed materials used in load cell construction. These considerations are important based on the project specifications for accuracy, quality and reliability in test and measurement.

Similarly, understanding the system configuration is another critically important factor to setting up the correct test for receiving accurate data.  A simple system configuration used for less-complex testing is known as one-cell or single load cell system.  They are popular for performance and durability testing.

How do one-cell systems work and what are the benefits and trade-offs?

One-cell systems are developed by using a tension cell and mounting it through a rod end bearing and clevises. If the cell is properly oriented with the dead end going to the support, the only other major consideration for this system is the elimination or reduction of possible parallel load paths. This type of simple system is attractive to some testing engineers and product designers because it is cost effective and can provide very accurate measurements when using Interface precision load cells.  It is important that the load meets the criteria for the test system.

In this figure, it shows a high-impact one-cell system platform. This one-cell system can withstand the high impact of rough treatment from certain applications such as large drums, LPG tanks and more.

The downside to using a one-cell system is that the center of gravity of the load must be placed directly on the mark for the system to work properly. However, this can be accounted for by positioning the fences as shown in the high-impact one-cell platform diagram, so that the center of gravity is located properly when the application you are measuring is shoved up against fences.

The actual load at the center of gravity for your application will be factored by the lever arm (as shown below):

The one-cell system works simply because the location of the center of gravity is under control. If the force on the primary axis of the load cell bears the same relation to the location of the center of gravity and the load under all conditions, the scaling will be correct. Whether using a one-cell or two-cell system, the system must be designed to retain its integrity.

This has been a brief overview of a one-cell system, which is detailed in Interface’s Load Cell Field Guide.

To learn more about these systems and to determine if your application test can utilize the simplicity and cost savings of a one-cell or two-cell system, contact our systems experts and application engineers.

Considerations for Steel, Stainless Steel and Aluminum Load Cells

In the world of force measurement and load cells, one size certainly does not fit all. There are thousands of different options for size and force ranges, and our load cell configurations vary widely based on the requirements of your project. Whether you are designing and testing products for the medical industry, or measuring force deep within a mine shaft, users need to be aware of certain force product details to ensure their getting the right tools for the job.

One of the critical considerations in the load cell selection process are the materials used in the construction of the load cell. If you did not already know, load cells can be made from several different metal materials. This list includes aluminum, steel, stainless steel, titanium, Inconel®, and even glass or carbon fiber.

Each material used depends on the end-use requirements and the need for strength, resistance, hysteresis, environmental concerns, output signal, size and weight, and budget.

For this post, the focus is on the three most used materials for load cells: aluminum, steel and stainless steel. Below is an outline comparing the different factors that make one material better than the others based on the testing requirements and use case.

Aluminum

Aluminum is a light and inexpensive metal, making it the most budget-friendly of the three. It is also the easiest to machine, as it does not require a heat treatment or secondary machining. Aluminum has a higher thermal conductivity, which can be a good or bad thing depending on your need. The hysteresis of aluminum load cells is also the lowest on this list. The most prominent benefit is that it can be used for constructing smaller load cells, so if size, weight, and total volume of the load cell is a key consideration for your project, aluminum would be the metal we’d recommend.

In adverse, when dealing with aluminum load cells it is important to understand that it is the softest material on this list, which means it is more susceptible to damage. This also means that it cannot handle as much stress, resulting in a lower output signal.

Steel

Steel is a stronger metal, so it is a bit more expensive than an aluminum load cell. It is still comparatively cost-effective. It also has the highest strength of the three materials outlined here. This means it is the least susceptible to damage and has the highest signal output. It also has higher environmental resistance than aluminum and less heat conductivity, which once again can be good or bad depending on the project.

The downsides to steel include the fact that it is more complicated to machine and requires a multi-step heat treatment operation. Compared to aluminum, the hysteresis is generally slightly higher for certain load cell designs. This can be remedied with additional engineering. It also does not provide the benefit of size, weight, and total volume flexibility that lighter aluminum provides.

In our opinion, steel provides the best value for a load cell in terms of money and performance, if size, weight and total volume is not an issue with your project or application.

Stainless Steel

Stainless steel is a stronger material than aluminum; however, it is not as strong as steel. The output signal performance for stainless steel load cells is somewhere in the middle of steel and aluminum. The main benefit of stainless steel is that it is the best material to use in a corrosive environment because of the metal’s environmental resistance properties.

The downside to stainless steel is that it is a bit more difficult to machine but does only requires a simple heat treatment process. It is also the most expensive metal of the three and has the highest hysteresis. We would recommend stainless steel when the user needs to collect data in a hazardous environment. Read more here about our Ex Rated products.

Understanding the difference between these materials is critical to getting the most accurate data from your force tests based on the environment and the nature of the product or system you are testing.

If you’re unsure about the requirements your project demands, be sure to reach out to us at 480-948-5555, or visit our website to be connected with an application engineer. We can discuss your specific challenge and help you select the load cell with the right material for your needs.

Contributor Ken Vining, Chief Engineer at Interface