Load Pins - SIL3 | PLe | IP68

Custom-Made Load Pin

load pins octogonLoad measuring pins or just load pins are connecting pins between force-transmitting machine elements that simultaneously enable the measurement of the transverse forces. These measuring pins thus assume the function of a conventional connecting element with additional measurement of the tensile and compressive forces acting on it. They replace regular pins or bolts and measure the stress that these components experience. The measurement is carried out using built-in strain gages (DMS). Load pins can be used to monitor forces in machines, cranes, elevators and systems.

 

octogon develops and produces customer-specific load measuring pins according to your specifications. This enables you to customize your own unique force sensor. The design of these sensors depends on your requirements. We adapt your measuring pin individually to your existing mechanics.

Advantages of the octogon load pins

  • Space-saving design, for direct integration into the force flow
  • Large measuring range or special measuring range for very large forces
  • Change of dimensions for easy retrofitting of existing structures without redesign
  • Available with integrated electronics
  • Use in potentially explosive areas is possible
  • IP68/IP69k
  • ATEX, IECEx, CSA

 

We support you in all steps along the way to the realization of your customer-specific solution. This includes the development of sensors, electronics, and software. With our know-how in all these areas, we are the ideal partner for developing your customized solution. We can manufacture smaller quantities by in-house specialists, but we can also convert the manufacturing process to the production of larger quantities.

Trust octogon when it comes to producing a high end system for your measuring needs.

 

Please check out our application report – Load measuring pins for theater engineering – to get a first impression of our load pins. Please contact us to get more information.

Customized Solutions

We produce individually made load pins or load measuring pins that exactly match the specifications of our customers. Our constructions are characterized by high accuracy and linearity. Depending on your applications, individual dimensions are designed and produced. Our engineering department has developed solutions for quick, safe and effective load-pin design CAD tools, based on many years of experience in manufacturing. As for vertical integration, octogon has partner machining shops dedicated to manufacturing our proof bodies, and giving us the full flexibility to produce any size of machining batches, from one-piece to the medium series. Our approach is ‘bidirectional’: we can manufacture according to existing designs or new designs, having verified that the dimensions and corresponding capacity match the safety requirements of the application concerned; or we can recommend optimised load pin dimensions based on requirements and the corresponding safety factors.

Load pinTo request a quotation, we will ask you for as much information as possible to ensure we can provide an appropriate solution. Thus, we need to know the load pin capacity, its dimensions (and ideally the corresponding mounting drawings), as well as the environmental conditions (temperature range, ingress protection, distance between pin and instrumentation, etc.). Based on our accumulated experience, we invite our customers and partners to describe their requirements so that we can suggest appropriate technical options.

Utility

The octogon load measuring pins or load pins offer solutions for load monitoring of cranes, winches, hoists, undercarriages, chain stoppers, rope endpoints, steel structures and pulleys. Our load pins are also used in the railway and automotive industries. The load pins are particularly robust and are also suitable for tough use in harsh industrial environments. Force measuring axes offer the advantage that they can often be built into the existing construction to save space. For example, instead of a bolt in fork bearings.

How does a load pin work?

Load pin or “Clevis pin” or “dynamometric axle” is a shaft instrumented with a Wheatstone bridge for measuring double shear deformation. Load pin design obviously has the benefit of integrating itself in a system assuring the mechanical interface between the components and providing information on the applied forces. The design principle relies on managing reduced load pin diameters at the areas of separation between the holding plates (flanges) and the central tool applying the main effort. The purpose of these reduced diameters is to create deformation zones where the strain gauges will be placed to ensure sufficient strain concentration that will guarantee accuracy and repeatability.

load pin function

Redudant load pins

For quite some time, the machine standard 2006/42/EC has been considered to be the main standard for designing and manufacturing machines of any kind. From this standard, a raft of new specialised standards has emerged, covering a significant range of applications.

One such standard is the EN61508 –“Functional safety of electrical/electronic/programmable electronic safety-related systems” which is widely regarded as the main source of information for designing safety-related systems.

Today, there is an increasing demand for components required for machine building that are compliant with safety standards. This is especially true for standards based on EN61508, such as EN62061 and ISO13849. It is worth noting that levels as high as SIL3 and PLe are quite common.

Octogon load pins may be used for these types of application. Thus, we have worked out a proper response to such needs by creating efficient documentation, reliability tests and a practical architecture for these applications.

This is why we are pleased to offer load pins that enable signal redundancy allowing for the design of safety-related systems with built-in auto-test. These load pins are made of two distinct strain gauge bridges and separate connection points. Such features help to reduce common cause failure. In the case of an mV/V bridge, information is provided on how to analyse and diagnose a failing signal.

Our sensors are tested, first by finite elements than by other means, such as field and laboratory testing or computer simulation. The results of these tests provide valuable information on project reliability and will help improve product specifications. Our experience in build and designing custom-made load cells enables us to design and choose the best tools to suit your reliability demands. We have three standard levels of testing, but more can be done if needed.

To guarantee safety and accuracy, these rates are based on a predictive calculation with a high safety rating. It is worth noting that these are given for one bridge allowing for several uses with different architectures. Years of experience demonstrate that those values are pessimistic compared to their counterparts in the field and thus guarantee the proper use with a standards mindset. Furthermore, the main cause of sensor failure is the change in its environment. Our team of experts and sales are ready to answer any questions you may have.

Integrated amplifiers and other feature

The octogon load pins are optionally available with integrated electronics or measuring amplifiers. The exact design provides high long-term stability and precisely reproducible measurement results. The load pins are vibration and shock resistant, the strain gauge full bridge compensates for temperature fluctuations. The measuring pins can be supplied with a permanently attached cable or plug. In addition to a customer-specific design, our measuring pins have other features as standard:

 

  • Integrated amplifier (4-20mA, CANopen, optional CANopen Safety, PROFINET, optional PROFINET PROFIsafe)
  • Durable design
  • Temperature compensated from -40 ... + 80 ° C
  • High EMC resistance of 200V/m
  • No zero point drift i.e. no recalibration required
  • Constant accuracy over the entire temperature range
  • Design for tensile and/or compressive forces
  • Limit load 150% and breaking load 300% of the nominal load
  • Safety classification PL c/SIL 1
  • Protection class IP66/IP67
  • Calibration in a simulated installation situation including test report

 

Optionally, our load and force measuring pins also offer the following advantages:

  • Increased ultimate and breaking load, e.g. 300/500%
  • Temperature compensated up to + 160 ° C
  • Redundant execution
  • Protection class IP69
  • External amplifier
  • Customized connections (cables and plugs)