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Smart Fastening

Smart Optics


Zmart is a representative organization of Kistler Remscheid (formerly Schatz) in Germany and AFS Advanced Connection Technology Research Institute in China. It was funded by Zwick China and has a German enterprise background. Its headquarters are located in Shanghai, and it has a joint laboratory for fastening connection technology with Huace Testing in Shanghai.

Smart Fastening

Committed to introducing advanced fastening assembly design, testing and verification technology to assist China in intelligent design and manufacturing. We specialize in providing software and hardware products and services for fastening connections throughout their entire lifecycle.

Smart Optics

Zimao Intelligent Optical Dimension Measurement is rooted in providing an overall solution for fasteners, strip steel, threaded steel, and round steel. As an industrial foundation, threaded steel has a basic tone for people's livelihood. The fully automatic intelligent optical reinforcement detection system breaks through traditional detection and lays a solid foundation for high-precision intelligent manufacturing.

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Friction coefficient testing machine

The quality characteristics of bolts and nuts during installation have a direct impact on the quality of bolted connections. Functional testing is the most important analytical method used in the assembly process. It determines the mechanical characteristics and functions of the fastening parts to ensure their quality. Simultaneously determine the friction coefficient, preload, and torque. And in this process, comply with international standards and simulate usage conditions as realistically as possible.

Ultrasonic axial force testing and analysis system

Unlike ordinary ultrasonic equipment, the Ifast ultrasonic axial force analysis and testing system Digital acquisition can be performed on the entire tightening process Short or long-term axial force monitoring of bolts Using the German professional fastener analysis and testing software TestXpert in conjunction with Kistler tightening equipment ® Conduct and process analysis

Thread Assembly Tool Testing System

In order to achieve reliable bolt connections in modern industrial production processes, a reliable tightening gun is crucial. Not only must the tightening gun be calibrated and certified before assembly, but it must also be repeatedly tested during the assembly process. The purpose is to ensure continuous high performance in order to achieve optimal assembly results and meet established standards.

Smart fastening wrench

Whether it is a soft connection tightening point or a hard connection tightening point, the torque decreases to varying degrees after completing the tightening process. How to find residual torque and how to find residual axial force has become an urgent problem that every tightening process engineer hopes to solve. The detection of residual torque values requires good tools to ensure the reliability and repeatability of the detection results. KISTLER's New Generation Intelligent Wrench Inspector has comprehensive residual torque testing function There are various built-in testing methods that can customize the detection mode according to customer needs.

Lateral vibration test bench

The lateral vibration test bench is equipped with an adjustable amplitude driving device, which is used for force sensors for lateral loads, high-precision displacement sensors, and sensors that can be replaced according to bolt size to measure clamping force and thread friction. During the vibration test, the test product is installed on the test bench according to the actual construction process, and the test conditions, such as test frequency and amplitude, are set using Kistler software. The experimental system will monitor and record in real-time the attenuation of clamping force, lateral thrust magnitude, thread torque, and other data that you are concerned about. The amplitude and frequency information during the lateral vibration testing process are controlled by the measurement and control unit.

Simulated assembly test system

In assembly testing, it is required that the test results obtained must be free of any "false evidence" - especially, if the position of the fasteners on the required test components is the actual installation conditions, this type of testing is considered challenging.

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Fully automatic steel bar shape and size measuring instrument

Zimao Intelligent Optical Dimension Measurement is rooted in providing an overall solution for fasteners, strip steel, threaded steel, and round steel. As an industrial foundation, threaded steel has a basic tone for people's livelihood. The fully automatic intelligent optical reinforcement detection system breaks through traditional detection and lays a solid foundation for high-precision intelligent manufacturing Breaking through the pain points of traditional manual offline measurement, switching between multiple measuring tools, and the inability to effectively save and trace data, we aim to create a new scenario for intelligent optical detection. The fully automatic intelligent optical steel bar size detection system (RM) can accurately and quickly measure the transverse and longitudinal ribs, width, height, and other dimensions of various types of ribbed steel bars in multiple scenarios through built-in rich steel bar detection standards. The developed data interface enables the sharing and export of test data in multiple ways

Fully automatic bolt size measuring instrument

A fully automatic optical bolt size measuring instrument developed from Germany for measuring the overall dimensions of fasteners in different industries. This device can automatically measure the geometric shape of rotating samples such as screws and bolts. Whether placed on site or in the laboratory, this equipment can greatly integrate conventional measurement methods, improving measurement efficiency. The convenient management mode of measuring big data will become a reliable choice for fastener enterprises to make a leap in quality.


Imess is an independent manufacturer of laser and optical camera inspection equipment. Since 1998, the Imess team has solved demanding inspection tasks in optical quality assurance and developed innovative inspection technologies to support your production line in achieving efficient, high yield, and high-quality levels.

Technical Focus: Analysis of the Truth about the Friction Coefficient of Locking Nuts

Classification: Course Introduction



Release time:2020-07-09 13:53


The thread friction coefficient angle and total friction coefficient angle curves of the locking nut are shown in Figure 6. From the thread friction coefficient curve, it can be seen that the friction coefficient changes with the tightening angle. After the nut fully fits the connected part, the thread friction coefficient and total friction coefficient decrease with the increase of axial force (or rotation angle), which indicates that if the tightening torque of the locking nut is relatively low, The setting or calculation of tightening torque cannot be based on the normal torque axis force, and needs to be calculated based on the actual friction coefficient, or a certain amount of screwing in torque needs to be considered in order to be more in line with the actual situation.

The friction coefficient of the support surface of the locking nut has relatively little change. After the nut fits the connected part, the friction coefficient of the support surface of the nut is basically consistent with the friction coefficient curve of the normal non locking nut. With the increase of the pre tightening force (bolt axial force), the friction coefficient of the support surface will not have a significant change. As shown in Figure 7.

For example, when installing nuts between the shock absorber piston rod and the mount, as shown in Figure 8, due to factors such as weight reduction, the outer diameter of the piston rod is not designed to be very large, and the effective contact surface is often only about 3mm, or even smaller in some designs. Therefore, on the premise of meeting the requirements, the tightening torque of the installation nut cannot be set too high, otherwise it may easily cause the mount to collapse or permanent plastic deformation, resulting in the attenuation of the tightening torque.

If the lock nut is tightened normally, and the lock nut is developed according to the required friction coefficient, it can be tightened according to the normal tightening torque without considering the issue of screwing in torque. Therefore, during the development of lock nuts, the friction coefficient test is also carried out at a guaranteed load of 75%, which means that the friction coefficient meets the required friction coefficient during normal tightening torque.



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