Strain Gauge Fundamentals
Strain gauges have been around for almost 80 years and continue to be key assets for measuring fatigue and testing materials for productivity and safety reasons. But how do I calculate material stress from strain? How can I select the right strain gauge and install it correctly?
HBM is commited to promoting a knowledge exchange about measuring strain with strain gauges. Our experts dug deep to provide their best answers for you about all the important questions regarding strain measurement using strain gauges. Click an option below to direct you to the content on the page.
- Basics of Strain Measurements and Experimental Stress Analysis
- Selecting the Right Strain Gauges, Adhesives, Covering Agents and More
- Installation of Strain Gauges: All there is to Know
- Reduction and Elimination of Measurement Errors
- Acquiring Data with the Right Hardware and Software
- Training, Webinars and References on Strain Measurements
1. Basics of Strain Measurements and Experimental Stress Analysis
How does an Electrical Strain Gauge Work
Watch this video to learn how an electrical strain gauge works.
Strain Measurement Glossary
A useful guide of technical terms to help you understand the precise concepts related to the fundamentals of strain measurement.
Experimental Stress Analysis
Experimental Stress Analysis (ESA) is the analysis of the mechanical stress state in materials, which is performed though experiments using strain gauge measurements. Learn the existing types of stress, their origin and states, or how to determine stress from measured strains by reading about it below.
Wheatstone Bridge Circuit
The Wheatstone bridge can be used in various ways to measure electrical resistance: For the determination of the absolute value of a resistance by comparison with a known resistance, for the determination of relative changes in resistance. Learn the basics and theory of operation.
Experimental Stress Analysis Reference Book
The strain gauge has become an essential tool in stress analysis, part optimization, safety testing and technical investigative work. It is also a major component used in the manufacturing of measurement transducers.
2. Selecting the Right Strain Gauges, Adhesives, Covering Agents and More
How to Select the Right Strain Gauge
Before the right strain gauge can be selected, the measurement goal needs to be clearly set. The main question to be considered is whether the strain gauge will be used for experimental tests or for transducers' manufacturing.
What is a Strain Gauge Rosette?
A strain gauge rosette is a term for an arrangement of two or more strain gauges that are positioned closely to measure strains along different directions.
Outlining Foil Strain Gauges
Foil strain gages are being used as proven sensor technology worldwide. Find out what a foil strain gauge is and what types are available on the market.
Selecting Adhesives for Strain Gauge Installation
The bonding materials have the task of firmly attaching the strain gauge to the measured object’s surface and transferring the object’s deformation without loss to the strain gauge. The various conditions and influences, and application options, require different bonding materials and installation methods.
Selecting Covering Agents for Strain Gauges
The quality of a measurement made with a strain gauge essentially depends on the type of installation and design of the measuring point. A thorough preparation of the installation surface, correct connection, and protective covering are important factors for problem-free results.
Wiring of Strain Gauges
The success of a measurement depends on the right connection cables. Not only do they have to transfer the measurement signals from the sensor to the DAQ system, but they also have to avoid interference signals and resist stress during their use. This article explains what to consider when choosing a cable for your strain gauge measurement.
3. Installation of Strain Gauges: All There Is to Know
How to install strain gauges - video series
Learn how to install electrical foil strain gauges efficiently. This video tutorial guides you through all the essential steps for a smooth strain gauge installation process.
Tips for a faster strain gauge installation
When you need to measure strain on an object, you are often doing so in a short timeframe. If the strain gauge is improperly installed, you can receive false measurements, which may cause you to spend even more time correcting these mistakes.
How to Prepare Material for a Gauge Installation
The Do's and Don'ts for Preparing a Successful Installation.
Welding or Bonding Strain Gauges?
How to identify the perfect connection for your strain gauges.
Tips for Correct Welding of Strain Gauges
Some environments are not suitable for bonding strain gauges, e.g. because of very low temperatures or excessive dust formation, e.g. on construction sites. Weldable strain gauges are the best choice for being used in this type of environments.
Bonding of Strain Gauges into Bolts
This article provides an instruction on how to install and use the 1-LB11-3/120ZW strain gauge from HBM. This type of strain gauge allows the measurement of axial load on bolt elements.
Wiring of a Bolt Strain Gauge
It is difficult to bond a strain gauge to a bolt while measuring the tightening stress. Normally, this requires the use of heavy machinery, but the application of special electrical strain gauges provides a simplified solution for measuring the axial load on bolt elements. The finalization after bonding the gauge in the bolt is shown in this helpful article.
Lead-Free Soldering of Strain Gauges
Learn how to perform lead-free soldering of strain gauges professionally and how to ensure a high reliability in your measurement.
Strain gauge installation on composites
Testing composite materials and structures is important to ensure their durability during use. It is essential to measure component deformation. Strain in the material is a critical factor determining damage effect and durability.
Strain Rate Measurement on PCBs
Based on the fact that detecting systematic failures at an early stage of development is absolutely essential, OEM manufacturers have increasingly started to ask their suppliers to check the mechanical quality of PCBs. Electrical strain gauges are designated to measure the deformation of printed circuit boards (PCBs) to an extremely accurate degree; this quick-step guide shows necessary steps, including the setup of a complete measuring chain.
Installation of Strain Gauges on Concrete Surfaces
Installing strain gauges on concrete surfaces does not have to be difficult! This article provides useful tips and tricks for your daily work.
4. Reduction and Elimination of Measurement Errors
Measurement Uncertainty: Less Errors, Better Results
This article addresses possible sources of error when strain gauges are used in experimental stress analysis and shows how to successfully assess measurement uncertainty already in the design stage.
Temperature Compensation of Strain Gauges
In this article we will show you which (unwanted) temperature effects can affect the measurement result when using strain gauges. You will also find practical assistance for how you can minimize these effects or compensate for them entirely.
Successfully compensating for lead resistances
Measuring points, e.g. at bridges or aircraft wings, are often located at greater distances from the measuring instruments. With measuring points that are not directly accessible, measuring instruments need to be connected using long cables.
Gauge Factor Deviation
In this article we will demonstrate why an exact parameterization of the gauge factor in the software is essential for reducing the measurement error in a strain measurement.
Fatigue Life of Strain Gauges
This technical article gives an overview of the fatigue life of electrical foil strain gauges and the limits for durability testing.
5. Acquiring Data with the Right Hardware and Software
How to work with strain gauges in catman AP
In this tutorial you will learn how to set up strain gauge rosettes by using HBM's catman®AP data acquisition software and a QuantumX MX1615 data acquisition system.
Strain gauge ¼ bridge calibration with shunt signals
This paper explains how fast and precise calibration procedures can be carried out automatically by means of simple shunt resistor switching technique.
Linearity and Sensitivity Error
This article describes the basic principles of strain measurement by means of strain gauges, from the strain itself via the variation in resistance to the eventual electrical signal, and compares the magnitude of error of the voltage-fed bridge circuit and the current-fed circuit.
6. Training, Webinars and References on Strain Measurements
Customer Stories
HBM sensors, measuring amplifiers and software products are used worldwide in thousands of development projects and a wide range of industries. Our case studies gathered on this page show the diversity in which HBM products are used.
Events & Seminars
The HBK Academy offers seminars and trainings for all knowledge levels from beginner to measurement application professional.