91狠狠色综合久久久夜色撩人,少妇高潮灌满白浆毛片免费看,欧美一级婬片A片免费老牛,性少妇videosexfreeXXXX片

Qingdao Chaofeng Plastic Machinery Co., Ltd. produces prestressed bellows equipment, focusing on more professional! !

After years of bridge construction, the country has continuously explored a more stable and robust bridge construction plan and material selection from experience. Let's talk about one of the links in the construction of bridges: the renewal of prestressed bellows, the early construction of bridges, we used metal bellows with galvanized or non-galvanized low carbon steel with spiral folding bite forming prestressed bellows, but this There are certain drawbacks to the kind of management:

1. After the metal corrugated pipe is processed, the coating will fall off. If the storage method is improper or the storage time is too long, the corrosion will occur, and the hole will be formed after the corrosion. In the subsequent construction, the slurry is easily blocked.

2. Because the metal bellows tube wall is thin and easy to burn, the welding slag is dropped by the steel bar during the construction process, and it is dropped onto the bellows, which makes it easy to burn the bellows.

3. Since the metal bellows is not very tough, the outer leakage section is easily broken at the end of the beam body, which affects the beam end when it is continuous and cannot be closely connected. It is easy to leak the blockage and block the inner space of the bellows, which affects the vacuum grouting.

4. When the beam is worn, it is easy to hang on the wall of the metal bellows, causing the bellows to accumulate, resulting in poor wearing.

5. The leakage of the corrugated pipe has a great impact on the subsequent work, and there are hidden problems in the construction quality. For example, if the beam is not smooth, the beam is not grooved, and the grouting is not smooth, which causes the partial grouting material to be insufficient.

Today we use plastic spiral molding instead of metal bellows to avoid the above problems.

Prestressed plastic bellows have the following advantages

1. It is wound into a spring-like structure through a special square tube, and is welded to a pipe at a high temperature by a high-temperature electrode of the same material. The pipe has the characteristics of flexible, compressible, stretchable and flattenable.

2, anti-chemical corrosion: not affected by acid, alkali, salt, no bacteria, algae breeding, no iron, no scaling.

3. Strong impact resistance: It still has good impact performance below freezing point and will not freeze due to water freezing.

4. Light weight: The density of polyethylene is less than 1, lighter than water, convenient for loading, unloading, transportation and installation. It does not require large lifting and transportation equipment.

5. The water resistance coefficient is low, which can increase the flow rate and flow rate by 30% compared with the diameter pipe.

6, good wear resistance: wear resistance is much better than metal pipe.

7. Convenient connection: It adopts two-way socket elastic sealing connection, which is convenient, fast, safe and efficient. At the same time, it can compensate the longitudinal expansion and contraction of the pipe due to thermal expansion and contraction, uneven settlement and large load impact.

8. Environmentally friendly products: The products are 100% recyclable and do not pollute the environment.

Main technical performance: Strong corrosion resistance The raw material of plastic corrugated pipe is high-density polyethylene material, which is not afraid of acid and alkali. Its corrosion resistance is much better than that of metal pipe, which can effectively protect pre-stressed steel bar from corrosion.

Hot products show