For more than 20 years, our user-friendly fastener test systems have provided OEMs and suppliers alike with accurate, reliable test data.
We offer a comprehensive line of user-friendly fastener test products,custom-configured into systems to suit your needs. Our systems are used in number of applications in industries such as automotive, aerospace & defense, and power generation. To complement fastener test systems, we offer expert technical support and services including testing, system maintenance and upgrades, and calibration in our A2LA accredited laboratory.
5 Things to Consider When Establishing a Threaded Fastener Program
1. What tests do you need to perform?
The following are typical fastener tests:
- Torque vs. Tension Testing
- Friction Coefficient Testing
- Locknut Prevailing Torque and Breakthrough Torque Testing
- Yield Determination Testing
- Assembly Strategy Testing
- Bolted Joint Analysis & Troubleshooting
- Bolted Joint Modeling and Analysis
2. What methods will you use?
The most comprehensive testing programs will include methods for modeling the joint,determining torque-tension characteristics and friction coefficients, and experimental testing of components and assemblies.
There are test methods for mechanical properties such as hardness, tensile strength, and torsional strength, as well as corrosion and hydrogen embrittlement, published by organizations such as the Industrial Fasteners Institute. These standards provide the baseline information necessary for proper interpretation of the friction coefficient, torque-tension, and angular ductility testing tests that are used to complete the evaluation of bolted joints. Once the basic material strength and friction coefficient information has been determined, an additional method, torque-angle signature analysis, can provide valuable information on joint strength and performance when applied to testing fasteners in bolted joints.
3. Where should you start?
The basic torque-angle signature is generally a good starting point for all analysis. It can be used to illustrate the influence of underhead and thread friction on the tightening process where an increase in friction, in either the thread or underhead regions, can result in a proportional increase in the slope of the torque-angle signature. The study of the slope of the torque-angle curve when the fasteners tightened is an important component of analyzing the performance of threaded fasteners in bolted joints.
4. How will you collect the data?
Before you can apply torque-angle signature analysis, you need a torque-angle recording device for measurement and curve plotting. The recording device should be able to display curves on-screen for immediate analysis and print or export the data for additional study. Tightening, audit, and release angle signatures for a given bolted joint can be displayed and printed. After careful review of the applied torque vs. angle-of-turn plot, you can use signature analysis to evaluate bolted joints for loss of preload due to settling, creep and relaxation, or vibration and dynamic loading. In addition, joint strength problems such as thread strip and embedment of bearing surfaces and material yield within the bolted joint are easily identified.
5. What equipment should you include in your test system?
We offer a full line of user-friendly products and accessories specifically designed for use in all of fastenertest applications. Our product offering includes:
- PortableData Recorder, Model 962
- LabMaster Professional, Model 3200
- Rotary Torque Transducers, Series PC9000
- Fastener Tension Load Cells, Series FT9000
- Fastener Torque-Tension Load Cells, Series FTA9000
- Force Washer Transducers, Series FT4000
- Fastener Drive System