Open-air use of industrial pipelines in the winter cold climate freeze blocking the situation, is a common problem, the cold appeared pipeline was frozen cases every year will appear many times, affecting the normal use of industrial functions. Subway station water supply and drainage, fire, fire hydrant in the low temperature also occurred to varying degrees of frozen pipes, which will affect the normal security of the subway, but also a certain degree of security risks, to a certain extent, on the operation of the underground railroad tracks has brought about an impact

 　　                   As the main component of the subway system, the fire pipeline system pipeline presents the occurrence of freezing and blocking, also is the important link of the whole system, therefore in the ground track planning and installing the pipeline, it is necessary to consider in advance to the fire pipeline system of the daily protection measures to ensure that the fire pipeline system in the low-temperature condition temperature are able to work normally to convey the small water source. In order to protect the Tianjin subway to drain pipe, fire pipeline, fire hydrant in low temperature can also be normal operation, at present, the most widely used is to use the electric heating trace cable system to maintain the temperature they need.

 　　                    Pick the electric heating cable system to take as the ground rail the pipeline heat preservation equipment, first of all we consider to install the convenience, at the same time also want to consider the heat preservation temperature uniformity, avoids the scalded pipeline, the ground rail of the contractor chooses the self-limiting temperature heat tracing cable, because of the self-limiting temperature electric heat trace cable in the installment also is able to cut at will, crosses the stacking wraps up, is very suitable for the ground rail this kind of underground pipeline to compare the complex system of the occasion to use.

 　　                           In the electric heating trace cable specification model selection, according to the ground track site different environmental temperature and the actual use of occasions need to select, select the self-limiting temperature heat cable can not use the thermostat, it has the function of the active temperature control, select the constant power electric heat cable can be used in the pipeline longer temperature request higher occasions, the detailed selection of the electric heat tracing cable, need to be based on the actual application of the occasion to decide.