Widely used in the construction of new drainage pipe

Traditional galvanized steel and cast iron drainage pipe to be easily general corrosion, since the major causes of transportation construction inconvenience to be replaced. Water supply and drainage pipes are mainly used plastic pipe, metal pipe and composite pipe of three.

Plastic Pipe

Plastic tube is a synthetic resin additive made by melt molding the products. Additives are plasticizers, stabilizers, fillers, lubricants, colorants, UV absorbers, modifier.

Plastic pipe commonly used are: hard PVC pipe (PVC-U), high density polyethylene pipe (PE-HD), cross-linked polyethylene pipe (PE-X), random copolymer polypropylene tube (PP-R), Polybutylene pipe (PB), engineering plastics acrylonitrile - butadiene - styrene copolymer (ABS) and so on.

Widely used in the construction of new drainage pipe

1.1 The composition of the raw materials of plastic pipe determines the characteristics of plastic pipe. The main advantages of plastic pipe:

(1), chemically stable, free from environmental factors and the impact of pipeline components within the media, good corrosion resistance.

(2) small thermal conductivity, low thermal conductivity, thermal insulation, energy-saving effect is good.

(3) hydraulic performance, pipe, smooth wall, the resistance coefficient is small and difficult to fouling, tube flow area does not change with time, channel blocking probability small.

(4) relative to the metal pipe, density, light materials, transport, easy to install, flexible, simple and easy maintenance.

(5) may have a natural bent or cold performance, the coil supply means can be used to reduce the number of pipe joints.

The main disadvantage of plastic pipe:

(1) poor mechanical properties, impact resistance, poor, poor rigidity, straight sex was bad, and thus control the density of high cards and hanger.

(2) flame retardant is poor, most of the combustible plastics, pyrolysis and combustion, it releases toxic gases and smoke.

(3) coefficient of thermal expansion, flexible compensation must be very stressed.

Performance of plastic pipes

Physical properties

The physical properties of plastic pipe. And aluminum-plastic composite pipe, steel pipe, copper pipe, plastic pipe channels the physical properties of the way, use, compensation measures and pipe insulation and so on. Such as:

(1) PVC-U, PP, ABS relatively high mechanical properties, be regarded as "rigid control", install better tomorrow. On the contrary, PE, PE-X, PB as a "flexible tube" for Concealed.

(2) the use of plastic pipes and heat resistance temperature determines the PVC-U, PE, ABS can only be used for cold water pipes, and PE-X, PP, PB may act as a hot water pipe. When building a water supply system and hot and cold water pipes when the heat resistance of a uniform as a major target.

(3) plastic pipe due to thermal expansion coefficient is high, especially in the plastic pipe as a water pipe, with flexible interfaces, expansion joints or bends of various compensation measures such as more heat. Among them, PE, PP and other polyolefins most. If this is not the time construction and installation of adequate attention, and to take appropriate technical measures, is extremely vulnerable due to the interface of expansion joints and pull off the problem.

(4) Since the low thermal conductivity, thermal insulation performance of plastic pipes superior in turn can reduce the thickness of insulation or no insulation. When different between the plastic pipe insulation of thermal conductivity of more than, but also with their respective wall thickness.

Performance under pressure

Performance is concerned with the pressure in the plastic pipes under certain conditions, to withstand the internal pressure and the destruction of time under constant pressure. To determine the design parameters and related to the quality of the pipe evaluation and monitoring. General conduct two tests: hydraulic pressure test and long-term high-temperature hydraulic pressure test. On the building water pipe used.

Health Performance

Physical health indicators. Where PE, PE-X, PP, PB and ABS easy to compliance. The PVC-U pipe should be used in the production of non-toxic PVC resin and stabilizers to meet health and hygiene performance requirements.

(1) Application of Plastic Pipe for Water

General PVC pipe as low cost, without considering the water quality impacts, water supply systems are preferred in the cold water pipe, and when the temperature is high, can be used or cross-linked polyethylene pipes and polyethylene pipes, polypropylene pipes, polybutylene tube.

(2) the application of plastic pipe drainage

Single material: PVC structure in various forms: core layer foam pipe, empty wall pipe, spiral pipe, spiral core layer foam and air wall spiral. The existence of some problems:

(1) thermal expansion coefficient, need to set the expansion compensation device to solve.

(2) stiffness of small, straight, poor management need to encrypt card, frame, hanger to solve.

(3) poor heat resistance, softening temperature is low, should limit water temperature control and limit the use of space and distance to solve the heat source.

(4) flame retardant poor across the floor, the Master roof roof, firewall, pipe shaft lining department needs to set fire ring and fire sleeve to solve.

(5), poor resistance to mechanical impact, need to strengthen the construction technology and careful construction to resolve.
(6), poor sound insulation, plastic pipe noise is greater than cast iron pipe, pipeline installation and pipeline located near Ming bedroom, the problem is particularly prominent. Noise reduction methods to improve the sound insulation pipe material, core layer foam pipe blank wall pipe is developed based on this idea; noise of the other way is to change the flow conditions, spiral pipe is developed based on this idea of. The idea of combining two methods is foam core layer spiral coil and air-wall development.

Under the same conditions, different structural forms of plastic drainage pipe, the noise determination results:

芯层发泡管>空壁管>螺旋管。" onmouseover="this.style.backgroundColor='#ebeff9'" onmouseout="this.style.backgroundColor='#fff'">General management> core layer foam pipe> empty wall pipe> spiral.

Application of plastic drainage tube drainage in the Place of the work carried out in cast iron pipe. Currently, plastic drainage pipe has a height of 100m in under construction for use in buildings, but very uneven progress in various areas. When the building height greater than, equal to 100m of high-rise buildings and not suitable for plastic drainage pipe of the occasion, cast iron drainage pipe can be used flexible earthquake.

Metal tube

3.1 Galvanized steel

Galvanized steel pipe is not meant to replace metal pipes have been replaced, nor that galvanized steel water supply in the area of the building be replaced.

3.2 Copper

Metal pipe is the most dominant copper, brass applications longer, more advantages, pipes and fittings are complete, the interface methods varied, more applications in hot water pipe, the main problem is that the existing copper fold amount of easily exceeded.

3.3 Cast Iron Pipe

Cast iron pipe and pipe water supply is not easy compared to corrosion, low cost and good durability, suitable for burying. Drawback is crisp, the weight of large and small length. Connections commonly used socket connection.

Clamp-style cast iron pipes is building a new drainage pipe, 20th century, access to international markets since the '60s, after decades of promotion and application, this pipe has been widely recognized by the international community. This pipe socket with a traditional style cast iron drain pipes have many advantages in comparison, is a replacement product, but because the pipe and fittings for relatively expensive, it has not been popular in the country to promote.

Composite Pipe

Complex including a lining of lead pipe, rubber lined pipe, glass pipe. Composite pipe mostly by working-level (which requires water corrosion), supporting layer, protective layer (requires corrosion-resistant) form.

Generally metal composite pipe for supporting material, lined with epoxy resin and cement based, it is characterized by light weight, smooth wall, low resistance, corrosion resistance performance is good; also to the support of high-strength soft metal, and non-metallic pipe internal and external sides, such as aluminum plastic composite pipe, which is characterized by corrosion and scaling pipeline wall will ensure that water quality; also have metal pipes in the medial and lateral non-metallic tube, such as plastic coated copper pipe, which is the use of plastic poor thermal conductivity from thermal insulation and protection.

According to the metal material can be divided into:

(1) Steel-plastic composite pipe;

(2) Stainless steel - plastic composite pipe, plastic covered stainless steel tube;

(Three) plastic coated copper pipe;

(4) aluminum plastic composite pipe, aluminum plastic composite pipe cross-linking;

(5) lined aluminum tubes.

It should be said composite pipe is the pipe diameter ≥ 300mm or more to the best sewer pipe. It combines a metal pipe strength, rigidity and non-metallic pipe corrosion advantages. But it is the slow development of a pipe. This is because:

(1) Both types of pipe together high price than a single pipe.

(2) thermal expansion coefficient difference of two large material, such as the bond is not strong and the ambient temperature and medium temperature change has more intense, easily torn off, which led to lower quality.

Composite pipe connections should use cold, thermal processing methods likely to cause the plastic liner stretching, deformation or even melting. Generally threaded, ring, clamp and other connections.