在直埋敷设的设计和施工必须真正了解加热管分为直埋敷设和直埋敷设无扩张，两种方法都有各自的特点和两个方法，设计一个合理的选择和建设直埋保温管的工作原理的应用是的，可靠的经济。
In the design and construction of direct buried laying must really understand the heating pipe is divided into direct buried laying and direct buried laying without expansion, both methods have their own characteristics and two methods, design a reasonable choice and construction of the working principle of the direct buried insulation pipe is safe, reliable and economical.
直埋保温管道敷设有补偿：通过自然补偿和补偿器（如方形补偿器和波纹管补偿器），将热应力降更低。直埋敷设没有补偿，这仅仅意味着对管道的热量没有补偿，而是热应力吸收。
Direct buried insulation pipe laying has compensation: through natural compensation and compensators (such as square compensators and bellows compensators), the thermal stress is minimized. There is no compensation for direct embedding, which simply means that there is no compensation for the heat in the pipeline, but thermal stress absorption.
直埋直埋保温管无需补偿安装、安装，热管先固定到一定温度后，再进行固定管焊接，当管道回温（低温）时，管道在拉伸应力作用下提前进行。当通过热管工作时，随着温度的升高，管道应力为零，在继续升温时，压缩应力增大，当温度达到工作温度时，管道的压缩应力、热应力仍小于许用应力。这样，管道就可以在不补偿设备的情况下工作。
There is no need to compensate the installation and installation of the directly buried and directly buried insulation pipe. After the heat pipe is fixed to a certain temperature, the fixed pipe is welded. When the pipe returns to temperature (low temperature), the pipe is carried out in advance under the action of tensile stress. When working through the heat pipe, the pipe stress is zero as the temperature increases. When the temperature continues to rise, the compressive stress increases. When the temperature reaches the working temperature, the compressive stress and thermal stress of the pipe are still less than the allowable stress. In this way, the pipeline can work without compensating the equipment.
第四强度理论中要求预热管道施工的补偿方法，在施工中会非常麻烦，在国内外也有许多工程实践，理论计算可靠，能保证。近年来，在的北京煤制气的热设计院的分类进行了分析，并对第三强度理论的方法和应力的应用。该方法充分发挥了钢的塑性潜力，施工方便，不预热。
The fourth strength theory requires the compensation method of preheating pipeline construction, which will be very troublesome in the construction. There are also many engineering practices at home and abroad. The theoretical calculation is reliable and can guarantee the safety. In recent years, the classification of the thermal design institute of coal gasification in Beijing, China has been analyzed and the application of the third strength theory method and stress. The method gives full play to the plastic potential of steel, which is convenient for construction and not preheating.
两不同埋深的考虑因素：直埋安装部署，嵌入深度来确定补偿，只考虑不会破坏管道的稳定性可能是由于地面荷载，从经济方面考虑，施工方便，方法等要埋在直埋补偿尽可能浅。上覆岩层的厚度应大于0.6米，不论管径大小。
Two different burial depth considerations: direct burial installation and deployment, embedding depth to determine the compensation, only considering that the stability of the pipeline will not be damaged may be due to the ground load, from the economic perspective, construction convenience, methods to be buried in direct burial compensation as shallow as possible. The thickness of the overlying strata shall be greater than 0.6 m, regardless of pipe diameter.
当直埋无补偿，考虑稳定性的管道埋深要求，一般覆土厚度、埋藏深度、稳定性，比有补偿直埋敷设时使用无预热无补偿电路，更小覆土深度应规则和城市热网设计规范（cjj34-90），一次覆土厚度7.2.15个执行，是直径大小成正比。
When there is no compensation for direct burial, the buried depth of the pipeline considering the stability of the requirements, general soil cover thickness, burial depth, stability, than the use of compensation for direct burial without preheating and compensation circuit, minimum soil cover depth should be rules and urban heat network design code (cjj34-90), the first soil cover thickness 7.2.15 implementation, is proportional to the diameter.
