There are more and more kinds of thermal insulation building materials on the market. In the meantime, the thermal insulation products of polyurethane materials are enough for consumers to see for a period of time. Ordinary consumers are still very concerned about the price when choosing and purchasing, so I will first look at the market price of polyurethane direct-buried thermal insulation tubes. According to the development situation of prefabricated polyurethane insulating pipes, the price of directly buried insulating pipes has a great fluctuation compared with the previous period, which is undoubtedly good news for consumers. The price factor is certain. Let's take a look at the most important part, the technical parameters, and how the polyurethane direct-buried insulation pipe is heating.

两种敷设埋设深度思索不同要素。

Consider the different elements of two laying depths.

(1)当必定选用有补偿直埋敷设办法时，埋设深度只思索由于空中荷载的效果不会毁坏管道的安稳便可，从经济、施工便利等方面思索。中选用有补偿直埋敷设办法时，尽量浅埋，普通覆土厚度大于0.6米即可，且与管径巨细无关。

(1) When the direct burial method with compensation must be selected, the burial depth only considers that the effect of air load will not destroy the stability of the pipeline, and considers from the aspects of economy and construction convenience. In the case of direct burial with compensation, shallow burial should be used as far as possible. The thickness of common overlying soil is more than 0.6 meters, and it has nothing to do with the diameter.

(2)中选用无补偿直埋敷设办法时，埋设深度要思索管道的安稳央求，安稳性主要与覆土厚度有关，普通比有补偿埋得深，中选用不预热的无补偿直埋敷设管道时，小覆土深度应按《城市热网规划规范》(CJJ34—90)第7.2.15条实行，覆土厚度应与管径巨细成正比。

(2) When choosing the non-compensated direct burial method, the burial depth should consider the stability requirement of the pipeline. The stability is mainly related to the thickness of the overlying soil, which is generally deeper than that with compensation. When choosing the non-preheated direct buried pipeline without compensation, the minimum depth of the overlying soil should be implemented in accordance with Article 7.2.15 of the Code for Urban Heat Network Planning (CJJ34-90), and the thickness of the overlying soil should be proportional to the diameter of the pipeline.

规划中究竟选用无补偿敷设仍是有补偿敷设办法，绳尺是直管道较长，中心分支较少，供热介质不逾越100℃时，我国供热信息网了解到应优先选用无补偿敷设办法，不然，应思索有补偿敷设办法。细致的热网主干线应选用无补偿敷设办法，而分支院子管网则应选用有补偿敷设办法，但如今有的规划者偏心有补偿敷设，应建议优化规划。热熔联接

In the planning, there are still compensatory laying methods. The length of the straight pipe is longer, the central branch is less, and the heating medium does not exceed 100 C. The heating information network of our country knows that the non-compensatory laying method should be preferred. Otherwise, the compensation laying method should be considered. Detailed heat network trunk line should be laid without compensation, while branch yard pipeline network should be laid with compensation, but now some planners have eccentricity and compensation, should recommend optimal planning. Hot melt connection

热熔联接在聚乙烯管道联接中是一种长见的联接办法，也是为经济可靠的一种办法。热熔联接普通有以下几种，热熔对接、热熔鞍形对接、热熔承插联接。

Hot melt bonding is a long-standing method in polyethylene pipeline connection, and it is also the most economical and reliable method. Hot-melt joints generally have the following kinds: hot-melt butt, hot-melt saddle butt and hot-melt socket joint.

大口径黑夹克

Large caliber black jacket

1、热熔对接

1. Hot-melt docking

热熔对接是在必定的压力、时辰和温度条件下，焊接端面被加热到焊接温度，然后彼此联接的办法。但是在聚乙烯管热熔对接进程中，易受环境及人为要素的影响。

Hot-melt butting is a method in which the welding ends are heated to the welding temperature under certain pressure, time and temperature, and then joined to each other. However, in the process of polyethylene pipe hot melt docking, it is vulnerable to environmental and human factors.

2、热熔鞍形对接

2. Hot-melt saddle docking

热熔鞍形对接联接进程比较艰难普通都在工厂预制。

Hot-melt saddle butt connection process is more difficult, usually prefabricated in the factory.

3、热熔承插联接

3. Hot-melt socket connection

热熔承插联接在《燃气用埋地聚乙烯管件》规范中已不选用，在给水管道中运用口径都很小，大口径热熔承插联接施工中，因管子重、对口与刺进深度艰难，无法确保联接质量。

Hot-melt socket connection has not been selected in the code of Buried Polyethylene Pipe Fittings for Gas Use. In the construction of large-caliber hot-melt socket connection, the quality of connection can not be guaranteed because of the heavy pipe, the difficulty of counterpart and penetration depth.