Precautions for buying a tensile testing machine How to choose a tensile tester
Choosing a tensile testing machine has always been a difficult decision. Faced with many similar products on the market, it is not know that the product of that manufacturer is a truly high-quality product, and which product is suitable for you. If you master the following precautions, you should be able to easily solve the problem of how to choose a tensile testing machine.
1. When purchasing a tensile testing machine, consider the tensile force range of the test material
The larger the load of the tensile testing machine is, the larger the size of the machine, and the smaller the load cell, the higher the accuracy. Of course, the larger the machine, the more expensive it is. Therefore, when choosing a tensile testing machine, it is not the bigger the better. But to adapt to the size of the product power range. Sensors on the market are divided into imported and domestically produced sensors. The domestically-made sensors are relatively cheap, but their poor accuracy will cause zero drift. On the contrary, the imported sensor has high accuracy and good repeatability, but the price is more expensive. The main part of the tensile testing machine is the sensor. During the test, the sensor outputs a force signal to the processor. If the output signal is inaccurate, the processed data must be inaccurate, and the tensile testing machine loses its ability to monitor and test.
2. The test stroke is also an element to pay attention to when choosing a tensile testing machine
The displacement measurement system that comes with the tensile testing machine only measures the distance moved by the beam of the tensile testing machine. If the elongation is required, such as measuring the elongation of rubber products, a large deformation test frame and a large deformation extensometer are required. For metal materials, a small deformation extensometer (metal extensometer) is added. Large deformation and small deformation (metal extensometer) are the absolute displacement between two points during the tensile process of the test sample, which has high accuracy. Choose the model according to the size of the product that your company needs to test, and the optional model with small sample volume and small tensile force: single-column tensile machine. However, the sample size is larger, and the tensile force is large, a double-column tensile machine is required. Generally, the stroke of the tensile testing machine is about 600mm. If the elongation of the material exceeds 1000%, you can choose a stroke of 1000 or 1200mm
3, the test speed of the tensile testing machine should also be taken into consideration
Some of the equipment on the market is 50~500 mm/min, and some are 0.001~500 mm/min. The former generally uses ordinary trapezoidal screw plus speed control motor or frequency conversion speed control system, which has lower cost and greater wear. Long time, too many tests will cause the joint board to shake, which will affect the accuracy of the test. Later soon the machine will be noisy and easy to break. The latter uses a servo system with a ball screw, which has high precision, constant speed and stability, low wear and good durability. The test repeatability is also good. The standards all stipulate the test conditions, what material and how much speed, because the measured force values are different because of the different speeds. There are not many tests, and it is more economical and practical to choose ordinary trapezoidal screw plus speed regulation motor or frequency conversion speed regulation system with little power.
4, the measurement accuracy of the tensile testing machine needs attention
Precision issues, including force measurement accuracy, speed accuracy, deformation accuracy, and displacement accuracy. Combine your own needs when purchasing. If you have high precision requirements, you need to pay special attention to this.
5, the standard configuration of tensile testing machine manufacturers
Three basic configurations of intelligence: host, microcomputer, and printer. If the microcomputer is powerful, you can print directly. In addition, it can also be equipped with an ordinary computer to perform complex data analysis, such as data editing, partial enlargement, adjustable report format, and statistical analysis of group styles. If equipped with a computer, the manufacturer will add the corresponding control system.
6, pay attention to the output results of the tensile testing machine
The output of the test results can be set arbitrarily: 8 items of force value, elongation, tensile strength, constant elongation, constant elongation force value, yield strength, elastic modulus, and large test force. This can be said to be the overall result output when the microcomputer is operated. The products of some foreign manufacturers can generally export these 8 items. Some domestic manufacturers can output 5-6 items, and some manufacturers can only output three items: strong value, average value, and small value.
7, pay attention to the main mechanical configuration of the product when purchasing the tensile testing machine
Transmission, there are screw transmission and rack transmission, the former is expensive, used for high precision, high test repeatability; the latter is cheap, used for low precision, low test repeatability. The lead screw plays a decisive role in the measurement of the precision of the tension. Generally, there are ball screws, trapezoidal screws, and general screws. Among them, the precision of the ball screw is high, but its performance depends on the operation of the computer servo system. The price of the whole set is also relatively expensive. The precision required by flexible packaging, namely 0.5-1% precision, can be achieved by using general lead screws and trapezoidal lead screws. Transmission includes gear transmission and chain transmission. The former is expensive and is used for high precision; the latter is cheap and is used for low precision. The main cost of sensors lies in their lifetime. Photoelectric sensing is one of the more advanced technologies, which can generally be used more than 100,000 times.
8. Pay attention to the manufacturer's after-sales service when purchasing
A more lasting after-sales service is a stronger guarantee after you buy the product. When purchasing a tensile machine, try to choose a manufacturer with a relatively long warranty period.
Liangong Group is the professional manufacturer of high cost-effective materials physical testing equipment, such as Impact tester, Universal testing machine, Compression tester, Bending tester, Torsion tester, Cupping tester, Hardness tester, etc. We also have ability to OEM for many big brands both at home and abroad. Here i attached our company brief product catalog for your reference. When you have any request about the testing equipment in future, please feel free to contact us.
