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.
Consider the different elements of two laying depths.
(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) 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.
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
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.
Large caliber black jacket
1. Hot-melt docking
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. Hot-melt saddle docking
Hot-melt saddle butt connection process is more difficult, usually prefabricated in the factory.
3. Hot-melt socket connection
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.
