The Difference between Double Wall Bellows and Plastic Bellows and Welding Bellows
HDPE double-wall plastic vacuum bellows has excellent chemical stability, resistance to aging and environmental stress cracking. The HDPE double-wall corrugated pipe produced from it is a flexible pipe. Its key performance is as follows:
Strong resistance to external pressure: The outer wall has a ring-shaped corrugated structure, which greatly enhances the ring stiffness of the pipe, thereby enhancing the pipeline’s resistance to soil loads. In this performance, HDPE double-wall corrugated pipes have a clear comparison with other pipes.
Advantage
Low construction cost: Under the condition of equal load, HDPE double-wall corrugated pipe only needs thinner wall to meet the requirements. Therefore, compared with the solid wall pipe of the same material specification, about half of the raw materials can be saved, so the HDPE double-wall corrugated pipe has a lower cost. This is another outstanding feature of this pipe. Convenient construction: Because the HDPE double-wall corrugated pipe is light in weight, easy to carry and connect, the construction is fast and the maintenance work is simple. In the case of tight schedules and poor construction conditions, its advantages are even more obvious.
Good low temperature resistance and impact resistance: The embrittlement temperature of HDPE double wall corrugated pipe is -70 ℃. Under normal low temperature conditions (above -30 ° C), no special protection measures are necessary during construction, and winter construction is convenient. In addition, HDPE double-wall corrugated pipes have good impact resistance of vacuum bellows.
Good chemical stability: Since HDPE molecules have no polarity, they have excellent chemical stability. With the exception of a few strong oxidants, most chemical media do not damage it. Generally, the soil, electricity, acid and alkali factors of the environment will not cause damage to the pipeline, do not breed bacteria, do not scale, and its circulation area will not decrease with increasing operating time. Plastic bellows were first developed in the 1950s, and have achieved rapid development in the last 20 years. Among the plastic bellows that have been developed and applied, according to the materials used in the production of plastic bellows, they can be divided into “HDPE bellows”, “UPVC bellows” and “PP bellows”. Among them, the current production of PVC plastic bellows is Big. The structural design of the plastic bellows adopts a special “annular groove” profiled cross-section. This kind of pipe has a novel design and a reasonable structure, which breaks through the “plate” traditional structure of ordinary pipes and makes the pipes have sufficient pressure and impact resistance.
Strength and good flexibility
Double-wall corrugated pipe refers to a plastic pipe with a smooth inner wall and a corrugated outer wall (the corrugated shape can be right-angled, trapezoidal, sinusoidal, etc.). It is formed by the simultaneous fusion extrusion of a corrugated outer wall and a layer of smooth inner wall. . In addition to all the characteristics of ordinary plastics, such as good corrosion resistance, high insulation and vacuum fittings, smooth inner walls, and low flow resistance, it uses special hollow ring stiffness and good strength and toughness. Under the same strength and rigidity requirements, the use of double-wall corrugated pipes can save materials by 30% -50% compared with ordinary plastic pipes. The technology is economical and easy to transport and install, which reduces the labor intensity of the construction staff and also reduces the labor intensity. The total investment of the project, but the deflection is small.
Application of bellows: single-wall bellows can be widely used for drainage and water permeability under light loads such as golf courses and sports fields; interior decoration wire casings; automotive wire casings; prestressed anchor cable casings; air conditioner drainage pipes, etc. . Double-wall corrugated pipes can be widely used in highways, slopes, golf courses and other heavy-duty conditions for drainage and water permeability; municipal sewage; telecommunications, power supply cable bushings and other occasions.
Welded corrugated pipe is a kind of highly flexible and flexible metal pipe made of many thin hollow diaphragms formed by stamping. It is composed of two hollow diaphragms formed in concentric circles. The inner edge is welded to form a diaphragm pair, and multiple diaphragm pairs are stacked together to form the outer edge to form a corrugated section, and then the two ends and end plates are welded to form a corrugated tube group. The other moving parts reciprocate together.
