What does strong silk mean, please teach me with a high finger

Refers to the shape, cardboard box, packing box is with national standard.

Usually we see that the wavy layer in the middle of the cardboard is corrugated, this kind of cardboard is also called corrugated cardboard, and the carton made of corrugated cardboard is called corrugated cardboard.

The shape of corrugated is divided into U-shaped, V-shaped and UV-shaped, U-shaped cushioning group can be better, V-shaped flat compression strength is good (feel is harder), UV shape combines the advantages of the two, the performance is between the two, and now basically use UV shape.

The corrugated corrugated type is divided into A, C, B, E, F, G, N and other flute types, and some other flute types are uncommon. Cartons are commonly used A, C, B, E type or their group beams or bridges, and cartons are used with E, F, G, N and other corrugated types. The data of A, C, B, E, F flute type can be checked in the national standard GB T6544-2008, the number of flutes per 30cm of G flute type is about 150, and the number of flutes is about 150 per 30cm, and there is no national standard for these.

Refers to the key buried in Qiaohong is the shape of the manuscript wide ant.

A short circuit between a live wire and a live wire occurs when two live wires of different phases exist at the same time, such as a three-phase alternating current. Three-phase alternating current means that the phase voltage value is the same, but the phase is different, that is to say, the time when they reach the maximum value is different, if the two live wires of the three-phase alternating current collide, there will be more serious consequences than the consequences of a short circuit of one fire and one zero.

Therefore, before the phase is verified, the unknown live wires cannot be connected to prevent the occurrence of interphase short circuits.

In China's civil three-phase four-wire (five-wire) power supply system, there are three live wires and one zero line. The voltage of each live wire and neutral wire is 220V. The wire between either two live wires is 380V.

In other words, a short circuit between a live wire and a live wire is more harmful than a short circuit between a live wire and a neutral line.

Refers to three-phase electricity. Between the three live wires is 380 volts, and each live wire is 220 volts from the neutral wire. Therefore, short-circuit faults between phases are not allowed

1. Phase-to-phase short circuit. 2. Burning equipment, causing disasters, etc. 3. Strengthen insulation.

Surface strength? Are you springback assayed? Or do you judge from a weak layer on the surface? These parameters can only be used as a macro reference, and there are too many objective factors to influence.

Therefore, please take the strength of the core pulling as the standard, the concrete is the overall structural solid, the internal strength is low is fatal, the surface is the gathering place of free moisture and external moisture, and some inferior admixtures (such as fly ash) are relatively light and easy to float on the surface of the concrete to cause low strength powder, just like you look at people, only the surface can be seen, and you can't know the inside.

The meaning of battle is not necessarily synonymous or antonym, just like writing Spring Festival couplets, clouds and rain, that is, the battle of two kinds of weather, can be regarded as nouns.

Original text: Clouds to rain, snow to wind, evening light to clear sky, Lai Hong to go to swallows, birds to song insects - from "Sound Rhythm Enlightenment East".

To come to Hong to go to Yan" is to come and go, two directional verbs, Hongyan is a bird.

Confrontation refers to the neatness of the confrontation in the couplet.

The couplet is opposed to each other, and after the upper couplet comes out, the lower couplet requires the relative part of speech, and some words have some fixed collocations, such as heaven to earth, sun to moon, etc., which are two of them.

Please tell me what problems occurred before your computer Hu Xiao, so that you can give targeted solutions according to your problems, if it is a small problem, you can try to install Tencent Computer Manager to solve it.

Differences: 1. Their characteristics are different.

2. They have different disadvantages.

3. They have different application ranges.

The characteristics and application range of aluminum profiles 1 series, 2 series, 3 series, 4 series, 5 series, 6 series, 7 series and 8 series are as follows

1. Aluminum profile 1 series.

Features: Aluminum content or above, good conductivity, good corrosion resistance, good welding performance, low strength, not heat treatment strengthening.

Application: High-purity aluminum (above aluminum content) is mainly used for scientific experiments, chemical industry and special purposes.

2. Aluminum profile 2 series.

Features: Aluminum alloys with copper as the main synthetic element, manganese, magnesium, lead and bismuth will also be added for machinability.

For example, 2011 alloy should be treated with safety precautions during the melting process (harmful gases will be generated). 2014 alloy for the aviation industry, high strength.

The 2017 alloy is a little less strong than the 2014 alloy, but it is easier to machine. 2014 Heat-treatable strengthened.

Disadvantages: Serious intergranular corrosion tendency.

Applications: Aviation industry (2014 alloy), screws (2011 alloy) and industries with higher temperature and use (2017 alloy).

3. Aluminum profile 3 series.

Features: Aluminum alloy with manganese as the main alloying element, non-heat treatment strengthening, good corrosion resistance, good welding performance. Good plasticity. (close to ultra-aluminum alloy).

Disadvantages: Low strength, but strength can be strengthened by cold work hardening. Coarse grains tend to occur during annealing.

Application: Seamless oil conduction pipes (3003 alloy), cans (3004 alloy) used in aircraft.

4. Aluminum profile 4 series.

Aluminum profile 4 series is mainly made of silicon and is not commonly used. Some of the 4 series can be strengthened by heat treatment, but some of the 4 series alloys cannot be heat treated.

5. Aluminum profile 5 series.

Characteristics: Magnesium-based. Good resistance, good welding performance, good fatigue strength, can not be strengthened by heat treatment, only cold working to improve strength.

Applications: lawn mower handles, aircraft fuel tank ducts, body armor.

6. Aluminum profile 6 series.

Generally, the mid-end and above shoe racks are basically 6 series or 7 series 6 series: characteristics: magnesium and silicon are the mainstay.

Mg2S is the main strengthening phase, and the most widely used alloy is the most widely used.

The strength is relatively low in the 6 series and the strength is relatively high in the 6 series. The frame at the middle end of Cyclone No. 2 is 6061, which has medium strength, good corrosion resistance, good welding performance, good process performance (easy extrusion forming) and good oxidation coloring performance.

Applications: Portable tools (such as: car luggage racks, doors, windows, car bodies, heat sinks, compartment shells).

7. Aluminum profile 7 series.

Characteristics: Mainly zinc, but sometimes a small amount of magnesium and copper are added. Among them, super-duralumin alloy contains zinc, lead, magnesium and copper alloys that are close to the hardness of steel.

The extrusion speed is slower than that of 6 series alloys, and the welding performance is good. The 7005 and 7075 are the highest grades in the 7 Series and can be heat treated and enhanced.

Applications: aviation (load-bearing components of aircraft, landing gear), rockets, propellers, aviation spacecraft.

No points, who made me enthusiastic.

All I can say is a rough idea.

Series 1 High thermal conductivity, corrosion resistance, good weldability, generally applicable to electrical appliances, heat exchangers, plates and strips.

5 series medium strength alloy has good formability, corrosion resistance, good weldability, and is generally suitable for marine vehicles, pipes, and bars.

Series 6 can be well continuously extruded, corrosion resistant, good surface treatment, generally suitable for complex cross-sectional hollow profiles, high-speed rail, subway.

7 series high strength welded structural alloy alloy for solid profile It seems that it can be used to make bullet shells Military The company has had this order before.

It's too general, but there are a lot of alloys in each department.