Page 65 - 《橡塑技术与装备》2021年12期（6期下半月 塑料）

材料与应用 唐木正·保温管用耐热聚乙烯（PE-RT Ⅱ）管道技术与应用

（4）固定支架，各种井室的施工质量直接影响工 方可进行，保温层有现场发泡施工和保温瓦施工两种
程质量和管道的使用寿命，如井室防水不好，将使部 方法，不管采用哪种方法施工，都不能出现环形空间，
件因浸水遭到破坏。因此，应认真施工，确保施工质量。 开裂、脱层等缺陷，保护层的做法有多种 ( 如高密度
（5）必须重视直埋管管道的打压，在满足打压条 聚乙烯和玻璃钢保护层 )，但都必须保证接头的整体
件下，首先进行灌水排净空气，然后分两步做 ： 性，严密性，防水性。
a．强度试验：把管道内的压力升至工作压力的 1.5 （7）回填土应在管道试压，接头，竣工测量，清
倍后，在稳压 10 分内无渗漏。 扫完毕后方可进行，且必须按直埋管施工特点回填规
b．严密性试验 ：把管内的压力降至工作压力时， 定厚度砂子，千万不可偷工减料。
用 1 kg 的小锤在焊缝周围对焊缝逐个进行敲打检查， 综上所述，随着 PE-RT Ⅱ 原料的发展，以及大
在 30 min 无渗漏且压力降不超过 0.2 个大气压即为合 口径、厚壁 PE-RTⅡ 管材生产技术的不断提高，PE-
格。 RTⅡ 保温管材的诸多优点更加突出，必将带来集中供
c．应按规范要求做好试压记录。 热管道系统的 “ 以塑代钢 ” 的 “ 革命 ”，国内多家石化
（6）现场接头保温施工。这一项内容是直埋管道 单位也正如火如荼的研制成功生产出优质价廉的 PE-
施工特有的，施工质量好坏直接影响使用寿命，必须 RT Ⅱ 原料，正逐步摆脱只能依靠进口 PE-RT Ⅱ 原料
引起足够重视。保温管现场接头保温须在试压合格后 的困境，PE-RT Ⅱ 保温管方兴未艾，前景大好。

Technology and application of heat resistant polyethylene (PE-RT Ⅱ )
pipe for thermal insulation

Tang Muzheng
(Tianjin Senpu Pipe Co. LTD., Tianjin 300270, China)

Abstract: In the field of gas and water supply, plastic has been used instead of steel, but in the field
of thermal pipeline, steel pipe is mainly used. However, the poor corrosion resistance of steel pipe seriously
causes the frequent problems of evaporating, emitting, dripping and leaking of thermal pipeline. The annual
maintenance causes increasingly prominent urban traffic problems. Therefore, in the field of thermal pipeline,
the technology of heat-resistant polyethylene pipe for thermal insulation brings hope to the thermal field.
The hot water delivery temperature of the secondary pipe network for heating is generally 60 ~ 95 ℃ , and
the delivery pressure is generally 0.4 ~ 1.0 MPa. The general low-density or medium density heat-resistant
polyethylene is ordinary type I PERT, but the pipe has low temperature resistance, pressure resistance and
ring stress performance. There is no problem of heat dissipation at the end of the third-stage pipe network,
but due to the high pressure and high temperature of the secondary pipe network, the ordinary type I heat-
resistant polyethylene PERT pipe can not meet the requirements. The properties of PE-RT Ⅱ material have
been greatly improved. The ring stress has been increased by more than 13%, and the pressure reduction has
also been greatly improved due to the increase of temperature. In addition, the creep resistance is further
improved and the long-term service performance is guaranteed, which makes it possible to use in hot water
transportation. However, the thermal pipe network is high temperature and high pressure after all. In order
to meet the requirements, the wall thickness of heat-resistant polyethylene pipe is still very thick. The heat-
resistant polyethylene pipe series S5, S4, S3.2, S2.5 are equivalent to the pipe diameter thickness ratio SDR11,
SDR9, SDR 7.4, SDR6. The pipe processing is very difficult, and the technical level and quality requirements are
high. This is also the focus of this presentation.
Key words: PE-RT Ⅱ (heat resistant polyethylene II); S value; hot melt; long term hydrostatic; creep
（R-03）

2021 第 47 卷 ·43·
年