Force Sensors
Force sensors are transducers that transform mechanical input forces like weight, tension, compression, torque, strain, stress, or pressure into an electrical output signal whose value can be used to...
Load Pins: Types, Applications and Benefits
Introduction
Descriptions of types of load pins and their use and a list of loan pin manufacturers
Topics covered in this article are:
- What are Load Pins?
- Considerations When Choosing Load Pins
- Applications of Load Pins
- Types and Calibration of Load Pins
- Working Principle of Load Pins
- Load Pins Signal Transmission
- And much more......
Chapter 1: What are Load Pins?
A load pin is a type of sensor designed to detect force or weight in numerous settings, such as research, control, measurement, and testing applications. They are specialized force sensors that transform applied force into an electrical signal. Load pins deliver reliable and precise measurements even under harsh conditions, including locations like outer space, seas, mines, and deserts. These sensors are highly valued for identifying applied forces and playing a crucial role in measuring and preventing excessive loads transmitted via pin joints.
One notable advantage of force sensors, particularly load pins, is the integration of internal strain gauges, a technology that has been employed for over six decades, broadening the application of load pins. This advancement is feasible because the pins feature a partial internal bore along the neutral axis to accommodate and shield internal instrumentation, effectively protecting the gauges from environmental factors. Load pins are crafted from high-strength stainless steel or alloy steels, ensuring optimal linearity and repeatability.
Standard load pins are universally adaptable, but the demand for custom load pins has grown when addressing unique needs. These can be tailored to exact application requirements and specifications. The custom design process is both cost-efficient and can be accelerated to fulfill urgent demands.
Load pins, also referred to as "Clevis pins" or "dynamometric axles," have a shaft-like structure incorporating a Wheatstone bridge for detecting double shear forces or loads from overhead equipment. Load cells, known as load pins, are utilized as pivot, clevis, sheave, and equalizer pins or other load-bearing components.
Diverse types of load pins are employed in cranes, winches, elevators, hoisting mechanisms, sheaves, shackles, bearing blocks, and pivot points. These pins function as force-measuring strain gauges. Similar to load cells, load pins track alterations in the electrical signal induced by force, which is then converted into weight measurements.
Chapter 2: How Load Pins Work
Load pins are highly specialized force measurement sensors that play a critical role in industrial safety and operational efficiency. At their core, these devices utilize strain gauges that are interwired into a Wheatstone bridge circuit. When voltage excitation is applied, the bridge arrangement produces a variable output voltage that is directly proportional to the force exerted on the pin’s elastic element. This process allows for the accurate conversion of physical force into a reliable electrical signal, enabling immediate load monitoring in real time.
- Force - Applied mechanical force is transformed into internal mechanical stress, following the principles of material strength calculations and load distribution analysis.
- Stress - Stress experienced by the load pin is converted into micro-level strain in accordance with Hooke's law, foundational in mechanical engineering and sensor calibration.
- Strain - Strain results in a variation in resistance, as detected by the strain gauge sensor integrated within the pin’s core.
- Variation - A relative change in electrical resistance modifies the output voltage from the Wheatstone bridge, providing a digital or analog signal proportional to the applied force or load.
When a load is applied to a load pin, minute deformation occurs within the pin body. The embedded strain gauge captures this deformation and converts it into a precise electrical signal by leveraging the Wheatstone bridge configuration. This method ensures exceptional measurement accuracy and is the foundation of load monitoring systems used in overhead cranes, winches, hoists, and other heavy machinery.
The sensing area of a load pin is precisely defined by two grooves, placed between the load-bearing surfaces. This structural design isolates the measurement zone, allowing for accurate detection of applied forces—whether tension or compression. Opposing forces, such as those from a lug or sheave, act against the pin, and the resulting pressure or force is measured and transmitted to the digital display or monitoring system.
One of the main advantages of load pins is their interchangeability with standard shaft, clevis, sheave, or equalizer pins, without reducing system headroom or compromising the machinery's operational safety. This attribute enables retrofitting for load sensing capabilities in existing equipment—improving workplace safety, providing overload protection, and helping to prevent costly equipment damage due to excessive loads or operational misuse.
Load pin technology is an integral component for industries operating heavy lifting or overhead machinery, including construction, marine, mining, energy, and manufacturing. By delivering reliable and continuous load monitoring, load pins help ensure adherence to regulatory requirements and enhance operational transparency. Constructed from corrosion-resistant stainless steel and housing robust, hermetically-sealed strain gauges, load pins are engineered to perform dependably in harsh industrial environments with exposure to moisture, chemicals, and extreme temperatures.
A load pin operates as an advanced strain gauge sensor engineered to sense force, load, tension, or weight. By utilizing the Wheatstone bridge circuit, the load pin translates physical deformation into a variable electrical voltage output, which is easily integrated with data loggers, PLCs, control systems, or load cell displays for real-time monitoring and feedback.
Using fundamental equations from material science and engineering, applied force is accurately transformed into stress, then into strain—yielding relative resistance changes measurable by precision electronics. The Wheatstone bridge circuit amplifies even the smallest resistance variations into clear voltage changes for instantaneous and reliable data acquisition.
Load pins have become the preferred force transducer for replacing conventional mechanical pins, such as those used in clevis, sheave, pivot, or equalizer applications. As soon as force is applied, the load pin’s geometric design ensures consistent deformation, which the internal strain gauge measures, validating the safety and stability of lifting operations. This innovation enables predictive maintenance, enhances equipment lifecycle management, and can be paired with wireless telemetry systems for remote load monitoring—a valuable asset for modern industrial applications.
Whether for load measurement, safety compliance, or real-time equipment monitoring, load pins deliver dependable measurements required for optimal performance in demanding working environments. Their seamless integration into existing structures, exceptional durability, and high accuracy make them a trusted choice in the field of force measurement and industrial weighing solutions.
Chapter 3: Considerations When Choosing Load Pins
Selecting the ideal load pin is a critical step in ensuring both safety and performance in many applications, including industrial weighing systems, structural monitoring, and crane overload protection. The key consideration with respect to load pin performance is any change in the geometry of the pin, the load-bearing structure, or variable loading conditions. Even minimal bending of a structure can alter the bearing surfaces or bending moment of the load pin, directly impacting its measurement accuracy and reliability. Since load pins are typically engineered to fit into existing mechanical assemblies, their dimensions are constrained by both the size and maximum load of the structure. Ensuring compatibility with the structure’s physical attributes and load requirements is paramount for optimal force measurement and system integration.
Capacity and Resolution
Determining the appropriate capacity and resolution is essential when choosing a load pin sensor for industrial weighing or force monitoring applications. The total amount of force—often measured in pounds, kilograms, or newtons—that needs to be measured, along with the smallest detectable change (the resolution), should align with the demands of your application. For accurate load monitoring and to prevent both overloading and excessive wear, the load pin’s rated capacity must meet or exceed the expected operating loads, while still allowing for a safety margin in demanding environments such as lifting equipment, hoists, or offshore oil and gas operations.
Modern load pins operate using strain gauge technology, producing millivolt outputs proportional to applied force. As resolution increases for more sensitive measurement, the individual millivolt signal becomes smaller and more difficult to detect minor force changes. For applications where high precision and overload protection are paramount, considering the interface with load cell amplifiers and digital indicators is essential to ensure clarity of the measurement signal and consistent data acquisition.
Environmental Considerations
The environmental conditions in which a load pin will be installed have a significant impact on its performance and longevity. The initial steps in the purchase process should include verification of compliance with regulatory standards such as NTEP (National Type Evaluation Program) and NIST (National Institute of Standards and Technology), especially if the load pin will be used in legally regulated or hazardous areas. Expert guidance from load cell manufacturers helps ensure the proper selection of a certified load pin that meets industry standards for safety and accuracy.
The selection of materials and protective features is equally vital. Environmental factors such as the presence of corrosive gases, liquids, or particulate solids can degrade the structural integrity of a load pin if not properly addressed. To combat potential damage, seek load pins made from corrosion-resistant stainless steel or with specialized coatings. Checking the device’s IP rating (Ingress Protection rating) is key, as it indicates the level of protection against dust, water, and contaminants—critical for applications in marine, offshore, chemical plants, or food processing industries. For additional durability, inquire about hermetically sealed load pins or those with custom environmental enclosures.
Temperature fluctuations can also affect the accuracy and lifespan of load pins. For installations in environments that experience extreme hot or cold conditions, select load pins with tested temperature compensation or wide operating temperature ranges. Furthermore, environmental vibrations, airflow, or wind loading may introduce noise or drift if not addressed—some advanced load pins include signal filtering or mechanical damping to counteract these effects.
Leading load pin manufacturers work closely with clients, offering guidance to ensure selected products meet both legal compliance and technical requirements. Certifications, such as those from NTEP for measurement accuracy and capacity, as well as conformance to NIST Handbook 44, guarantee a high level of quality assurance. These standards not only simplify the approval process but also provide peace of mind when integrating load cells into critical industrial lifting, safety monitoring, or process control applications. For specialized needs, consult manufacturer application engineers for advice on custom pin design, data interface options, or wireless load pin solutions for remote monitoring.
- Load Pin Selection Checklist:
- Determine maximum and minimum load requirements (capacity range)
- Assess resolution and signal output needs (precision and sensor compatibility)
- Verify certification and standards compliance (NTEP, NIST, ISO)
- Consider environmental exposure (IP rating, material, corrosion resistance)
- Account for extreme temperature or vibration requirements
- Consult with manufacturers for application-specific recommendations
By carefully considering these performance and environmental factors, and leveraging expertise from established load cell and load pin manufacturers, users can optimize their system for long-term accuracy, reliability, and safety in demanding industrial environments.
Chapter 4: Applications and Calibration of Load Pins
A load pin is a sensor used in various research, control, measuring, and testing applications to quantify force or weight. The load pin force sensor transforms a force into an electrical signal. The load pins offer reliable and accurate measurements even in harsh environments like space, the ocean, mines, and deserts. Identifying applied forces, measuring overloads, and preventing them from being transferred via the pin joints are some examples of the utility of load pins due to their design.
The internal strain gauge's inclusion into force sensors, and load pins, is one of their key benefits. The internal gauge technology enables a wider application of load pins. This wider application is made feasible because the pin is not entirely solid; instead, a small internal bore is machined along the neutral axis to house and safeguard the internal instrumentation, separating the gauges from the outside world. In addition, the load pins are made from high-strength stainless or alloy steel materials to maximize linearity and repeatability.
Numerous applications are suitable for standard load pins, and as the number of applications for load pins has substantially increased, custom pins have also grown in demand and necessity. Therefore, a significant benefit is the option to acquire a custom load pin made to fit their requirements.
Applications for Load Pins
When a force acting on a structure needs to be quantified, the necessary equipment is often expensive and difficult to install. Load pins are a key element which solves that problem as they are installed as another direct component of an assembly to replace non-instrumented pins or shafts already existing in the load path. When a force is applied to the instrumented load pin, the strain gauges produce an output signal that allows load measurement, including high stress and overload conditions.
Various force measurement applications across various industries use load cells, load pins, tension links, bolts/studs, and other force sensors and systems. Simple force-measuring systems to cutting-edge products like NASA's Mars rovers, the Space Shuttle launch pad, and hydrostatic or submersible vehicles utilized deep below the ocean's surface are all examples of uses. Generally speaking, there are two types of applications for load cells:
Load Cell Use for Research and Testing
Using load cells for product, component, and system research, development, and testing falls under this first category. For example, load sensors are frequently used for testing and requirement verification for new hardware designs, force distribution analysis, operational force determination, and overload or structural capabilities. In addition, computer modeling and simulation tools are increasingly used as design tools for new hardware development. As a result, the load cells are frequently used to collect real-world load and force data.
Load sensing is also used to test established, mature hardware designs when use is expanded to encompass new requirements or some form of enhanced scope or capacity and additional testing is necessary. Load cells are not just used to test/evaluate new hardware designs.
Load Cell Measurement and Control Applications
The second utilization area is centered on product or process control applications rather than new or used hardware design or testing. In these situations, the load cell products regulate a certain force or operation to guarantee that the desired force is achieved, either directly monitored or incorporated into a full-fledged automated system. The load cell systems can alert or set off various programmed actions or events. As an alternative, other control applications include monitoring forces during an operation to guarantee that specific overload or unsafe circumstances, if encountered, are identified promptly.
Several applications and illustrations of how load cells are used in control applications to make sure process force is attained, or conversely, that it is not over-ranged or exceeded are provided in this area.
There are several applications for load pins; a selection is given below.
- Bearing Blocks
- Brake Anchors
- Structural Tests
- Flight Simulators
- Winch/Crane/Lifting Systems
- Landing Gear Clevis Joints
- Mooring Lines/Lanyards
- Sprocket/Pulley Axles
- Bombay/Cargo Doors
- Railroad/Towbar Connections
- Armament Suspension Systems
- Rocket Reaction Forces
- Aircraft Wing Joints
- Conveyors
- Test Machines
- Hydraulic Actuators
- Nuclear Fuel Rod Control
- Robotic Pin Joints
- Sheave Axles
- Ground Support Equipment
Load Pins Calibration
Many industries, including aerospace, marine, oil and gas exploration, the military, aviation, and the automobile, depend on load pins. It is necessary to show that force measurements are correct to avoid product liability and safety concerns. Compliance with ISO and AS certifications frequently focuses on traceability to NIST standards.
Calibration at regular intervals is required to ensure the load pin is operating within specifications, as all load pins are susceptible to degradation through usage, abuse, drift, or aging. Electrical impact, mechanical effects, instrumentation errors, loose wires, etc., can reduce load pin performance and reliability over time. As particulate matter can accumulate around load pins even in clean surroundings, failure to inspect or clean load pins is another important aspect that might result in operational problems. Performing annual calibrations helps to guarantee optimal performance.
Since all load pins are subject to deterioration due to use, mistreatment, drift, or aging, calibration at regular intervals is necessary to ensure the load pin is performing within its specification. Over time, wear and tear can degrade performance and make a load pin less reliable due to electrical influences, mechanical effects, instrumentation faults and loose cables. Failure to inspect or clean load pins is another significant factor that can lead to operational issues, as particulate matter can build up around load pins even in clean environments. Regular, yearly calibrations ensure optimal performance.
Leading Manufacturers and Suppliers
Chapter 5: Types of Load Pins
Load pins are manufactured from robust stainless-steel or other high strength alloy steels. They have a high corrosion resistance and can be designed for use in harsh environments. Load pin systems include thermal compensation, are easy to install and maintain, and are an economical solution to difficult load measurement conditions. An optional wireless transmitter has integrated electronics that enables monitoring without cables. Properly installed and calibrated load pins can be drop-in replacements, minimizing installation costs, mitigating the requirement to add additional hardware components to the load path.
Dual Bridge Load Pins
Twin bridge, two independent strain gauge circuits, is offered by clevis pins. Dual bridge transducers can utilize just one bridge for measurement while saving the other bridge as a backup, or they can use both bridges simultaneously for control and measurement.
With either single or dual connectors, electrical terminations can be either radial or axial (dual shown below). Cables that are permanently attached are also an option.
Wireless Load Pins
In situations where cable installation may be challenging, expensive, or unwelcome, the wireless load pin offers a high-performance wireless telemetry solution. The system offers great measurement precision, resolution, and stability combined with long battery life. In addition, software tools enable rapid and simple device configuration, calibration, data logging, and recording interfaces.
Benefits and Features of Wireless Load Pins
- Without a license, 2.4 GHz telemetry
- Transmission range of up to 800 m (2,600 ft.)
- Extended battery life
- Ideal for sensor systems with one or more sensors
- With the wireless transmitter installed, load a pin or shackle bolt
- The transmitter can be used with either unique or common clevis pins.
The Uses of Wireless Load Pins
- Aerospace
- Industrial Weighing
- Automotive
- Construction
- Energy
Standard Force Sensing Load Pins/Bolts
Force sensitivity load pins, sometimes called clevis pins or clevis bolts, are special load sensors that utilize the internal strain gauge transducer technology created and used in flat load cells and tension links. By replacing the existing shear pins, clevis bolts, load pins, shear axles, and many other types of pinned joints for the aerospace, automotive, marine, and military industries, these load pins, and clevis bolts provide exact force measurement.
Features
The strain gauges are installed at two sites at the clevis to clevis eye interfaces and are sealed inside tiny axial holes within the load pin. The strain gauges are carefully positioned and orientated at a neutral plane concerning one particular direction of pin loading to detect just those strains caused by the shear stresses at these two sections.
The four strain gauges—two at each location—are electrically connected to create a full bridge. Since each strain gauge's signal is additive, the output of the bridge is proportional to the total loads communicated by the pin's shear planes. The circuit often includes temperature compensation, signal trim (if applicable), and balancing resistors that terminate in suitable connector sockets or integral cables.
Detailed calibration data up to 500,000 lbs. are included in standard force sensing load pins/bolts. Therefore, standard force sensing load pins/bolts need higher capacity calibration data. Although calibrations are meant to mimic installed settings, it is advised that an in-place calibration be carried out to take into account any installation, tolerance, and alignment impacts that may alter sensor data.
- Precision Load Sensing
- Rugged
- Internally Sealed Strain Gauges
- Easy Installation
- Direct Force Measurement
- High Strength Stainless Steel
Applications
These standard clevis pins are often utilized in new applications where the designer can construct the exact load pin joint around the standard clevis pin specifications to maximize the performance of force measurement. Additionally, the conventional clevis pin may suit existing load pin joints or can be added by using bushings or changing the clevis assembly.
Standard Wire Rope Load Pins
Force sensitivity load pins, sometimes referred to as clevis pins or clevis bolts, are load sensors that use internal strain gauge transducers and are used in flat load cells and tension links. By swapping out the current clevis pins in typical wire rope socket gear, these load pins and clevis bolts provide precise force measurement and monitoring.
Standard Force Sensing Shackle Load Bolts
The force sensing shackle bolts use the internal strain gauge transducer technique, also used in their flat load cells and tension links. By swapping out the current pins or bolts in typical Crosby anchor and chain shackles, these shackle bolts provide precise force measuring and monitoring.
Detailed calibration data up to 500,000 lbs. are included with standard force sensing shackle load bolts. Therefore, standard force sensing shackle load bolts need higher capacity calibration data. Although calibrations are meant to mimic installed settings, it is advised that an in-place calibration be carried out to take into account any installation, tolerance, and alignment impacts that may alter sensor data.
- Easy Installation: Standard Crosby or Skookum shackle the RCP and SCP series and replaces bolts/pins
- Precision Load Sensing: The whole strain gauge bridge circuit is bonded and sealed inside a small hole along the longitudinal axis of the bolt.
- Durability: Since strain gauge installation is sealed inside tiny pores, it is self protecting.
- Accuracy: The overall inaccuracy caused by repeatability and non-linearity for force sensing loads or clevis bolts is often less than 1% of the specified load.
Applications
Clevis pins or bolts are incredibly resilient even under the worst weather and working conditions. As a result, these goods are widely applicable and have a long useful life. And are being utilized on numerous installations that call for force measuring in a shackle application.
More Applications
- End of Whip Line Winch
- Clam Shell
- Boom Pendant Cable Support
- Crane Hoist Cables
- Mooring Lines
- Bridge Support Cables
- Cable Dead End
Instrumented Load Pins for Sheave Applications
Sheave and pulley systems use a variety of instrumented load pin designs. The user can create a sheave around our basic CPA clevis pin or have a bespoke pin made for an existing sheave design with a specific measurement capacity and geometry, enabling easy installation and maximizing measurement capacity. Observing the pin's reaction load, the instrumented sheave pins are frequently used to gauge line tension. The following formulae can be used to calculate the line tension.
Constant Wrap Angle
Axis of Maximum Sensitivity: Position the load sensing pin's keeper flat so it is perpendicular to the axis of maximum sensitivity at a wrap angle of one-half. In this case, the wrap angle is 105 degrees, and the angle is divided by two to get 52.5 degrees. See the specification illustration below.
Ø= Wrap Angle
T = Line Tension
P = Resultant Force on Sheave Pin
Line Tension (T): Utilize the specification picture and the following calculations to calculate the tension in a line by measuring the reaction force on the sheave:
P = 2T cos (Ø/2) or T = P ÷ 2 cos (Ø/2)
Example: For a measured sheave load of 10,000 lbs. and a wrap angle of 105. The formula: can also be used to calculate the Line Tension (T).
Variable Wrap Angle
The bi-axial clevis pin's cross section is an example of gauge alignment. The load component Py will be sensed by the gauges designated Y, whereas the load component Px will be sensed by the gauges marked X. The resultant force P is calculated using constants (Kx, Ky) derived from calibration data* and the outputs from the two bridges as Ex and Ey.
Px = Kx Ex
Py = Ky Ey
and the resulting force P = [Px]² + [Py] squared²
Calculating the Line Tension (T) and Wrap Angle () can be done by using the following:
T = Py² + Py² ÷ 2Px and Ø = 2 inverse cosine ( P ÷ 2T)
Where P, Px, and Py are cross-talk effects corrected.
Chapter 6: Working Principle of Load Pins
The advantage of load pin design is that it may be integrated into a system, ensuring the mechanical link between the components and providing data on applied forces. The most typical examples include clevis pins set at dead-end anchor points or the upper sheave/equalizer beam of EOT cranes, used to suspend a chain hoist to its trolley, on a fairlead sheave of a winch, at the head of a hydraulic cylinder, etc.
The design approach is based on controlling smaller load pin widths where the holding plates (flanges) and the center tool exerting the most force are separated. These smaller sizes produce deformation zones where strain gauges will be installed to assure accuracy and repeatability by ensuring sufficient strain concentration.
The mechanical resistance of the load pin is determined by these smaller sizes, which explains why a load pin cannot always replace a simple shaft because doing so would necessitate increasing the diameter. Instead, aeronautic-grade steels' high resistance level makes up for this mechanical change.
The safety coefficient of the clevis pin is defined by the load pin diameter, reduced diameters, and size of strain gauge pockets to reach the neutral fiber of the pin and concentrate the required strain:
- FORCE: permissible overload: 150% of nominal capacity, breaking load >300%
- HOIST: permissible overload: 200%, breaking load >500%
- LIFT (lifting people or hanging equipment over people): permissible overload: 400%, breaking load >1000%
The maximum overload for which we promise the load pin won't permanently distort is known as the permissible overload ("0" offset).
Strain limitation on the various shaft components serves as the foundation for the design requirements (the most critical being those parts in contact with the holding plates that are generally thinner than the central tool). For "FORCE" load pins, the range must stay between 150 and 200 N/mm2; for "HOIST" load pins, the range must be between 100 and 120 N/mm2; and for "LIFT" execution, a strain of about 50 N/mm2 is the target. If the working span of the pin is greater than those strain values, the shortfall of the span is made up of a larger diameter.
These design requirements ensure the mechanical and fatigue resilience of the load pin and the mechanical mounting supported by the load pin. In any event, aeronautic-grade steels with 1150 to 1350 Mpa (or N/mm²) are utilized to comprehend the well-known safety aspects.
The accuracy of the load pin is affected by various circumstances. First, if the load pin diameter is too close to the size of its active span, its accuracy performance will be poor (>3%). This low accuracy performance is due to the ratio diameter/operation span (load pin supports and deformation zone). Good decoupling is essential because if the holding plates make contact with the central tool (or sheave in hoisting applications), they will cause friction that will increase uncertainty, cause non-repeatability problems, and, in extreme cases, prevent the signal from returning to "0". After all, the releasing strains will not be able to be applied to the load pin due to friction (the central tool/sheave will remain blocked in the loaded position). There should be air gaps of at least 0.5 to 1
A load pin is designed to move with just one effort. When a force is introduced at an angle to the operating direction, the output signal is greatly reduced for any applied force that remains constant once the angle exceeds 10°. The reduction becomes even greater as the angle increases. For example, when the wire rope is wrapped around a sheave at an angle of 180°, the load pin will be acting in the direction of both wire rope falls; in the event of a 90° wrap angle configuration, the load pin will be operating at a 45° angle from both wire rope falls. For designs where the force direction is continually changing, it is also possible to use double-direction load pins (X and Y).
Thus, the pin diameter decreased, and the span of the mechanical components retaining and applying stresses to the pin affected the clevis pin's sensitivity (output signal). The "FORCE" design will produce between 1.5 and 2 mV/V, the "HOIST" design about 1 mV/V, and the "LIFT" version about 0.5 mV/V. But it also relies on how the load pin is mounted. Half-moon components that support and exert force on the pin will produce a particular sensitivity. However, a different sensitivity will be produced by mounting the pin diameter entirely. The span of the matching mounting, as well as the hardness of the material holding the pin and exerting stresses on it, both have an impact on load pin sensitivity.
It becomes clear that a single live calibration on a live mounting can produce the true image of applied efforts with the matching output signal by combining the mechanical mounting with the design and hardness of the material utilized. Any laboratory calibration will be more of a pre-calibration with its associated uncertainty than a calibration on a live mounting with actual stresses, even using a calibration instrument replicating identical mounting conditions.
Dimensionally, load pins as small as 7 mm in diameter can be made, and there is no upper limit; a load pin with a diameter ranging from 360 to 480 mm has already been constructed. By following a detailed examination of the application, nominal capacities between 2000N (0.2t) and 30MN (3000t) and even beyond can be created. For most applications, external bonding of strain gauges is used (models 5000-5300-5600 with visible pocket covers). In contrast, internal bonding of strain gauges (design 5050) is reserved for submerged/subaerial requirements (up to -5000m and more), high-pressure applications (up to 700 bars), or ATEX Ex d requirements (explosion-proof).
Load Pins Signal Transmission
In terms of output signals, load pins can be fitted with inbuilt amplifiers for the following signals in addition to the conventional mV/V output: 4-20mA, 0-10V (and derived), RS485, Modbus, and CAN. In addition, analog amplifiers can be tuned to allow overloads without signal saturation using a range from "0" to nominal capacity or any other capacity.
Conclusion
Load pins are a type of load cell that are used as replacements for clevis, sheave, pivot, normal shaft, and equalizer pins. They are exceptionally reliable and have capacities of over 500,000 pounds (2224.11 kilonewtons).
Load pins have a bored center that contains force measuring strain gauges that measure the change in the electrical signal caused by applied force.
Load pins are used in any application that has a repeatable load path. They are beneficial to several industries, including agriculture, chemical processing, energy production, and marine cargo and port shipping operations.
Although there are standard types of load pins, manufacturers work with customers to create custom load pins for unique and special applications.
Interface load pins are machined using high tensile strength stainless steel that can be used in environments that are exposed to harsh environmental conditions.
