第1層：工作鋼管層
Layer 1: Working Steel Tube Layer
依據(jù)設計和客戶的請求普通選用無縫管(GB8163-87)螺旋焊管(GB9711-88;SY/T5038-92)和直縫焊管(GB3092-93)。
Seamless pipe (GB8163-87), spiral welded pipe (GB9711-88; SY/T5038-92) and straight welded pipe (GB3092-93) are usually selected according to design and customer's request.
鋼管外表經過的拋丸除銹工藝處置后，鋼管除銹等級可達GB8923-1988規(guī)范中的Sa2級，外表粗糙度可達GB6060.5-88規(guī)范中R=12.5微米
After the surface of steel tube is treated by advanced shot peening rust removal technology, the grade of steel tube rust removal can reach Sa2 level in GB8923-1988 specification, and the surface roughness can reach R=12.5 micron in GB6060.5-88 specification.
第2層：聚氨酯保溫層
Layer 2: Polyurethane Thermal Insulation Layer
用高壓發(fā)泡機在鋼管于外護層之間構成的空腔中一次性注入硬質聚氨酯泡沫塑料原液而成。即俗稱的“管中管發(fā)泡工藝”。其作用一是防水，二是保溫，三是支撐熱網自重。當保送介質溫度為：-50℃—120℃時，選用硬質聚脲酸酯泡沫塑料做保溫層。
A rigid polyurethane foam plastics raw liquid is injected into the cavity formed between the steel pipe and the outer protective layer by a high-pressure foaming machine at one time. That is commonly known as "tube-in-tube foaming process". Its function is waterproof, heat preservation and self-weight support of heat network. The rigid polyurethane foam is chosen as insulation layer when the temperature of delivery medium is -50 ~120 ~C.
第3層：高密度聚乙烯維護層
Layer 3: High Density Polyethylene Maintenance Layer
預制成一定壁厚的黑色(黃色)塑料管材，其作用一是維護聚氨酯保溫層免遭機械硬物毀壞，二是防腐防水增強級聚氨酯保溫鋼管特 點：用鋼管做外維護層，具有強度高。不易損壞且能接受較大上部荷載的特性，為到達短命命，對鋼外套管需停止防腐處置。滾動支持構造設計合理，滾動摩擦力小，固定支座受力減小，其力學剖析原理簡單，管道穩(wěn)定性、平安性得到較大進步。真空層徹底根絕了空氣層存在的熱傳導和熱對流、極大地降低了熱損失。與空氣層構造相比，在同等保溫厚度下可降低外壁溫度8-13°c。抽真空安裝徹底處理了外鋼套管內壁容易被熱濕空氣腐蝕的難題，大大進步了直埋蒸汽管道的運轉壽命。產品壽命進步到30年。
Prefabricated black (yellow) plastic pipes with a certain wall thickness. Its function is to protect the polyurethane insulation layer from mechanical damage. The second is the characteristics of anti-corrosion, waterproof and reinforced polyurethane insulation pipes: using steel pipes as external maintenance layer, it has high strength. It is not easy to damage and can accept large upper load. In order to achieve short life, the steel casing should be stopped anti-corrosion treatment. The design of rolling support structure is reasonable, the rolling friction is small, the force of fixed support is reduced, the mechanical analysis principle is simple, and the stability and safety of pipeline have been greatly improved. The vacuum layer completely eliminated the heat conduction and convection in the air layer and greatly reduced the heat loss. Compared with the air layer structure, the outer wall temperature can be reduced by 8-13 C under the same thermal insulation thickness. Vacuum extraction installation has thoroughly solved the problem that the inner wall of the outer steel casing is easily corroded by hot and humid air, and greatly improved the operation life of the directly buried steam pipeline. The product life has been improved to 30 years.
This article is supported by polyurethane insulating steel pipe manufacturer. For more details, please click on our official website at http://www.qndr49.cn. We will provide you with satisfactory service wholeheartedly.
