How about Jin Cheng s pile foundation acoustic tube?

It can be used in urban water pipe network systems, urban and rural drinking water pipelines, agricultural irrigation pipelines, chemical industry, chemical fiber, food, forestry, printing and dyeing, pharmaceutical, light industry, papermaking, metallurgy and other industries of material and liquid transportation pipelines, post and telecommunications lines, power wire protection casings, and mining mortar transportation pipelines.

Choosing a high-quality acoustic tube is a very important part of construction, so how to see the performance of the acoustic tube? Jincheng Pipeline Technology, a well-known expert in the industry, will take you to uncover the "secret" of the acoustic tube.

1. Yield point.

When the stress exceeds the elastic limit when the stress exceeds the elastic limit, even if the stress does not continue to increase, the acoustic tube or specimen will continue to undergo significant plastic deformation, which is called yield. The stress value when the yield phenomenon occurs is the yield point.

2. Yield strength.

The yield point of the acoustic tube is different depending on the metal used, and the yield point of some metal materials is very inconspicuous, and it is difficult to measure, so in order to measure the yield characteristics of the material, the yield strength is generated, and the yield strength is equal to a certain value (generally the stress of the original length.

3. Tensile strength.

The limit of the stress value reached by the material used in the acoustic tube during the tensile process from the beginning to the time of fracture is the tensile strength, which indicates the ability of the acoustic tube to resist fracture, and the tensile strength corresponds to the compressive strength and bending strength.

4.Elongation.

After the metal material used in the acoustic tube is pulled off, the percentage of the length of its plastic elongation to the length of the original sample is the elongation, which can also be called elongation.

5. Yield ratio.

The ratio of the yield point (yield strength) to the tensile strength of the acoustic tube, we call it the yield ratio, the larger the yield ratio, the higher the reliability of the structural parts, usually the yield ratio of carbon steel is, low alloy structural steel is, alloy structural steel is.

6.Hardness. Hardness indicates the ability of a material to resist hard objects pressing into its surface, it is one of the important performance indicators of metal materials, usually the higher the hardness, the better the wear resistance, the commonly used hardness indicators are Brinell hardness, Rockwell hardness and Vickers hardness.

1) Brinell hardness.

The hardened steel ball of a certain size is pressed into the surface of the material with a certain load, held for a period of time, and after the load is removed, the ratio of the load to its indentation area is called the Brinell hardness value.

2) Rockwell hardness.

When the Brinell hardness is greater than 450 or the sample is too small, the Brinell hardness test cannot be used, we need to use the Rockwell hardness measurement instead, the test method is: use a diamond cone with a top angle of 120°, or a diameter of .The 18mm steel ball is pressed into the surface of the measured material under a certain load, and the hardness of the material is calculated from the depth of the indentation, which is divided into three scales according to the different hardness of the tested material.

It's pretty good, and there's no problem with meeting all kinds of engineering needs.

I'm from Hebei Institute of Technology, it's not good, I recommend not to work in any school unit in general.

Yes. I didn't know there was such a factory.

Ben Bai in 2011

The salary of the department is 2500, and the master's degree is more than 4000 du

This salary is all there is, including the basic.

DAO salary, car subsidy, housing subsidy, etc.

Do not provide accommodation, free lunch, nominal five-day work system, do research and development must be voluntary overtime, the salary level of the general company in Zhuzhou Road take 125 bus 20 minutes to Laoshan District **, in the north of Qingdao in general, the house is about 800 to 1,000 per person, Qingdao consumption plus rent or so.

The company is suitable for the worst students in 211 schools, and the middle students who are not 211 in school.

1 The soft and hard requirements of this major are relatively high, and you must be familiar with the professional courses of electricity, at least one language foundation, and you want to C C++, etc. 2 At least you need to school courses such as genetic algorithms, artificial intelligence principles, automatic control, etc. 3 What professional courses to take during the postgraduate examination are determined by the school you apply for Each school is different, you must learn mathematics and English well before the exam, in order to learn easily in the future, you must also learn professional courses well 4 The tutor values your comprehensive ability, including the basic level of English professional courses and innovation ability 5 The most famous Tsinghua University, Beihang University, Beijing Institute of Technology, China University of Mining and Technology, Zhejiang University, etc. 6 Think about modern military radar, navigation, medical intelligent instruments, can use such things The intelligent explosion-proof detector during the Olympic Games is an example, the scope and field of employment are relatively good, of course, the better the thing is, the more difficult it is to learn, good luck!!

Measurement and control belongs to a new type of major, in the past, only graduate students had this discipline, and now the undergraduate has also opened this discipline, and it is on the rise This is a wide-caliber major, and the future development direction is control theory and control engineering, instrument science and technology. In the future, we will focus on the development of intelligent instrumentation, and the future is very good. Business Training Objectives:

This major cultivates senior engineering and technical talents who have the basic knowledge and application ability of precision instrument design and manufacturing, measurement and control, and can be engaged in the design and manufacture of relevant technologies, instruments and systems in the field of measurement and control, scientific and technological development, applied research, operation management and other aspects in various departments of the national economy. Business training requirements: Students in this major mainly learn the basic theory of optics, mechanics and electronics of precision instruments, measurement and control theory and design methods of related measurement and control instruments, and are trained in modern measurement and control technology and instrument application, and have the ability to apply and design and develop measurement and control technology and instrument systems in this specialty.

Graduates should acquire the following knowledge and abilities: 1. Have a solid foundation in natural sciences, humanities, arts and social sciences, and the ability to correctly use the Chinese language and writing; 2. Systematically master the basic knowledge of a wide range of technical theories in the professional field, mainly including basic knowledge of mechanics, electronics, optics, measurement and control, market economy and enterprise management; 3. Master the contemporary measurement and control technology and experimental research ability combining optical, mechanical, electrical and computer, and have the ability to design and develop the measurement and control technology, instruments and systems of the specialty; 4. Strong foreign language skills; 5. Have strong self-learning ability, innovation consciousness and high comprehensive quality. Main disciplines:

Optical Engineering, Instrument Science and Technology. Main courses: Precision Mechanics and Instrument Design, Precision Mechanical Manufacturing Engineering, Fundamentals of Analog Electronic Technology, Fundamentals of Digital Electronic Technology, Principles and Applications of Microcomputers, Fundamentals of Control Engineering, Signal Analysis and Processing, Precision Measurement and Control and Systems, Engineering Optics.