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44902ofryvrvl
Dec 18, 2021
In General Discussions
The pressure aluminum pipe used is affected by itself and the external environment, and is in industrial production. It will cause the pipeline to vibrate. If the pipeline is affected by vibration for a long time, it will produce a sense of fatigue in the stress-concentrated part, which will cause the pipeline to break, which will cause a more serious safety accident, which will cause the leakage of the medium, so in the production It is necessary to minimize the vibration of aluminum pipes to avoid unnecessary safety accidents. 1 Pressure aluminum pipe vibration source analysis The aluminum pipe, bracket and connected equipment of the pressure aluminum pipe constitute a structural system. When there is an exciting force, the system will vibrate. Vibration sources of pressure aluminum pipes can be roughly divided into two categories: from the system itself and from outside the system. ①From the system itself, there are mainly vibrations of the machine connected to the aluminum pipe and vibration caused by the unstable flow of the fluid in the pipe; ②From the outside of the system, there are earthquakes and wind, etc. Vibration is a kind of alternating load to the pressure aluminum pipe, and its degree of damage depends on the size of the excitation force and the vibration resistance of the aluminum pipe itself. The main influencing factors are as follows: ① The natural frequency of the air column. The fluid filled in the aluminum pipe is an elastic air column. Whenever the compressor or the cylinder of the pump sucks or exhausts air from the aluminum pipe, the air column in the aluminum pipe is disturbed and vibrates. ② Mechanical natural frequency. The piping system is a continuous elastic body, and there is a natural frequency of the structure. If the machine excitation frequency is equal to the natural frequency of the piping structure, resonance will also increase the vibration of the piping system. Vibration caused by pipe flow pulsation. The aluminum pipe fluid is in a pulsating state under the action of a compressor or a pump. When flowing through aluminum pipe components such as elbows, reducers, tees, valves, etc., the force on the aluminum pipe is also constantly changing. A certain exciting force that changes with time is produced, and vibration is generated. ④Vibration caused by two-phase flow. The aluminum tube pipeline system is mostly dominated by the two-phase flow of gas and liquid. It should be that the compressibility of the gas is greater than that of the liquid. When the two-phase flow in the aluminum tube pipeline forms a flow pattern with larger bubbles, different areas The air bubbles are compressed differently, causing the aluminum pipe to vibrate. ⑤ Liquid shock vibration. The valve in the aluminum pipe is suddenly closed or opened, and the fluid velocity changes suddenly, which has a great impact on the piping system and generates vibration. Liquid shock is a very important source of vibration in the aluminum pipe piping system. Sometimes it can cause great changes in the pressure in the aluminum pipe, and in severe cases, the pipe may burst. ⑥The fluid velocity in the aluminum pipe is too fast, and the turbulence is formed due to the separation of the fluid boundary layer, which causes the aluminum pipe to vibrate. ⑦Earthquakes and wind from outside the system threaten aluminum pipes. Once a strong earthquake occurs, buried aluminum pipes may be damaged. Although overhead pipelines are not directly affected by earthquakes, most of the aluminum pipe supports are based on the ground. , When an earthquake occurs, the support frame is damaged, and the aluminium coil collapses accordingly, causing damage to the ring. The influence of wind is irregular. As long as the aluminum pipe is fixed firmly, although the aluminum pipe will vibrate due to interference, the effect is not very large. 2 Measurement of vibration of aluminum pipes For a pipe system with vibration, to reduce or eliminate vibration, it is necessary to fully grasp the relevant parameters and take appropriate vibration damping measures. ① Vibration measurement of aluminum pipe structure: Vibration measurement is to measure the displacement of vibration. The measuring device is composed of three parts: sensor, amplifier and recorder. The sensor is a speed sensor, and the output voltage is proportional to the measured vibration speed. The signal obtained is converted into a displacement signal after one integration, which is amplified by the amplifier and sent to the recorder. As shown in Figure 1) ②Aluminum pipe pressure pulsation measurement: The most basic part of the airflow pressure pulsation measurement device in the aluminum pipe is the sensor, amplifier and recorder. The function of the sensor is to convert the signal of pressure change into a signal of power change, and the amplifier accurately linearly amplifies the electrical signal obtained from the sensor, and pushes the recorder to record the pressure pulsation curve. As shown in Figure 2) ③The natural frequency measurement of the aluminum pipe system: generally use the tapping method to excite the pipe system, tap one or several points of the aluminum pipe to record the attenuated vibration signal, and quickly analyze the signal. The natural frequency of each order, this method is very simple and commonly used. 3 Measures to reduce and eliminate the vibration of the pressure aluminum pipe 3.1 Change the natural frequency of the aluminum pipe According to the vibration theory: the multi-degree-of-freedom vibration equation of a mechanical system can be expressed by the matrix differential equation: MX+CX+KX=F where: M Is the mass matrix, X is the node displacement vector, C is the damping matrix, K is the stiffness matrix, and F is the interference force and the excitation force vector. It can be seen from the above formula that to change the vibration characteristics of the pipeline system, the following considerations can be considered: ① Install a balance weight on the aluminum pipe system and change the mass matrix to change the natural frequency of the system to avoid resonance of the aluminum pipe.
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44902ofryvrvl
Dec 17, 2021
In General Discussions
The Appeal model is a human hair wig with naturally wavy hair. The half-length hair can be styled in many ways. The hair volume is kept very natural and therefore corresponds to the amount of hair in European standards. The wig is available in 9 different colors. Wig appeal A wig dream in real hair When you hold this wig in your hand for the first time, you will be amazed at the softness of the hair. But once you put the wig on, you will be surprised how soft and perfect this wig fits. The hood (Montour) is made of extremely skin-friendly materials and is therefore ideally suited for sensitive scalps. The top of the head has a film approach, which creates the effect as if the hair was growing directly out of the scalp. The rest of the wig is sewn onto a soft net with extremely thin strands. Cut and styling The hair is naturally wavy and layered, which results in many styling options. In our pictures we blow-dry it once smoothly and once in a naturally wavy shape. Since the wig is made of real hair, you can dye it on. However, it must be taken into account that the hair must never be dyed lighter. Our tip: The Volume Diamond Spray from our HonestHairFactory hair care range. You can use it to blow-dry your hair smoothly, but also to freshen up the natural waves. Wig advice Advice is everything. We will only find the right wig through detailed advice. This takes some time, so we always plan at least one hour of consultation time. This time is well invested, because what use is a valuable wig if it doesn't fit you at all? We are therefore happy to take a lot of time for you.
Human hair wig appeal content media
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44902ofryvrvl
Dec 17, 2021
In General Discussions
The instrument - water distiller is mainly composed of three parts: condenser, evaporator and electric heating tube. The main material is made of stainless steel sheet and stainless steel seamless tube, with beautiful appearance. The electric heating part adopts immersed electric heating tube, which has high thermal efficiency. Condenser part: The heated water vapor passes through this device. Distilled water can be produced by cold and heat exchange, and it can also be disassembled. Evaporator part: When the water source in the pot exceeds the bottom of the water adding cup, it will automatically overflow from the overflow pipe on the cup. The boiler body adopts the disassembly type, which is convenient to wash the scale in the pot. There is a drain valve at the bottom, which is convenient for draining water or replacing the stored water at any time. Electric heating tube part: This part is at the bottom of the evaporating pot. The electric heating tube is immersed in water and heated to make the water boil to obtain steam. The heating time depends on the power of the electric heating tube. Whether the electric heating tube is heated or not is realized by the electrical control part. The electrical control part is composed of high-power relays, temperature thermal switches, etc.
The main structural characteristics of the water distiller content media
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44902ofryvrvl
Dec 11, 2021
In General Discussions
Winter has arrived in Animal Crossing: New Horizons, and in addition to snowy trees and holiday events, players may want to consider participating in a New Horizons advent calendar gift exchange organized by the Animal Crossing: New Horizons community. To participate in the New Horizons advent calendar gift exchange, players must have an animal crossing bells account. Additional new decorations and items are available, some of which would make excellent gifts for the advent calendar swap. Two distinct events will take place during the months of December and January, which players can look forward to. In contrast, Animal Crossing players may find the holiday season to be long and cold if they do not participate in either of these two major celebrations. Reddit user CriticalBlackberry49 proposed an idea for a community-driven advent calendar that would count down from Christmas until the end of the month of December in order to brighten the holiday season. An explanation of how two or more players can swap a gift every day can be found in the Reddit post linked above. This ensures that each participating player has at least one gift to open in their mailbox each morning, regardless of how many others are participating. Additionally, the exchange could be used to assist players in acquiring seasonal items such as snowflakes and holiday-themed DIYs during the winter season. Because of their participation, everyone who participates in the advent calendar swap will benefit from it, as they will increase their chances of finishing their holiday decoration arsenal as a result of their participation. Additionally, in addition to exchanging a final gift, players were encouraged to display items that they found particularly appealing or even swap gifts that did not fit with their individual island themes. Imaginative celebrations such as an advent calendar exchange can be organized by players in buy bells animal crossing new horizons, allowing fans to stay connected no matter how far apart they are geographically. Daisy Mae is the mastermind behind the Daisy Mae's Pick'n Patch event, which will take place in the Animal Crossing: Pocket Camp spin-off game during the months of April and May 2020 Daisy Mae is also the creator of the Animal Crossing: Pocket Camp spin-off game A new farm mechanics tutorial will be provided at the conclusion of this event, in which Daisy Mae will teach players how to obtain the rare farmer seeds that are only available during this event However, despite the fact that Daisy Mae was only recently granted access to the Animal Crossing phone app, her engagement and enthusiasm for the game's events shows her to be a well-involved and enthusiastic community member who is eager to share her farming expertise with others
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44902ofryvrvl
Nov 26, 2021
In General Discussions
Quality assurance is a proactive, process-based method to avoid problems with quality control of products and services before they are developed and implemented. In summary, quality assurance should therefore be viewed as a preventive measure. Manufacturers implement quality assurance by planning and documenting the quality assurance process, tools such as B. Select checklists to protect yourself and train your employees accordingly. As soon as the process has been fully mapped and carried out, regular factory audits are usually also carried out to check whether the quality assurance process is being adhered to and to identify ways of optimizing it. What is quality control? Quality control takes place after the quality assurance process has been established. In contrast to quality assurance, which is based on a structure and effective planning, quality control is based on products or services. The primary goal of a quality control process is to ensure that a product or service is free from defects and that quality requirements are met. In a sense, therefore, quality control should be viewed as a more reactive method. The reason? While quality assurance plans how high-quality products or services can be produced or provided, quality control identifies errors in the finished products / services and helps to correct them before delivery to the customer. Comprehensive test and inspection procedures are used in quality control to monitor the quality of a manufacturer's products. As you can see from the differences between quality assurance and quality control, there will be fewer quality problems and costs in the quality control phase when a manufacturer is fully in control of their quality assurance. Because if you have quality assurance and quality control under control, you have lower COQ - and thus higher profits.
What is quality assurance? content media
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