Application of electric heating tape in natural gas pipelines

Electric heating tape consists of a conductive polymer, two parallel metal wires, and an insulating sheath. Its key feature is the high positive temperature coefficient of the conductive polymer. The wires are connected in parallel, automatically adjusting the output power according to the temperature changes of the heated system, automatically limiting the heating temperature, and can be cut to any length or extended within a certain range. It also allows for multiple overlaps without the risk of hot spots or burnout. Today, we will introduce the application of electric heating tape in natural gas pipelines in detail.

I. Installation of Electric Heating Tape in Natural Gas Pipelines

1. Secure the electric heating tape to the pipeline every approximately 50cm using fiberglass pressure-sensitive tape or aluminum tape.

2. When laying it flat, attach the electric heating tape to the lower 45-degree side of the pipeline as much as possible.

3. Leave a 1m length of electric heating tape at the power supply point and the end of the line.

4. Lay the tape according to the design drawing [winding coefficient] (the coefficient should be an integer, and it should be laid flat to reduce the number of joints). 5. All heat sinks (such as supports, valves, flanges, etc.) should have the required length of electric heating tape reserved according to the design drawings. This section of electric heating tape should be wrapped around the heat sink body and secured.

6. The heat sink should have the required length of electric heating tape as designed. Self-regulating electric heating tapes can be stacked or interlaced. The wrapping method should allow the heat sink to be easily removed for maintenance or replacement without damaging the electric heating tape or affecting other circuits. Where two-way or three-way fittings are used, 40cm of electric heating tape should be reserved at each end.

II. Spiral Wrapping of Electric Heating Tape in Natural Gas Pipelines

If the wrapping coefficient is 1.4, meaning a 5m pipeline requires 7m of electric heating tape, during construction, first fix both ends of the 7m long electric heating tape to a 5m long section of pipeline. Then, wrap the loose electric heating tape around the pipeline and secure it.

III. Construction Method of Multiple Electric Heating Cables in Natural Gas Pipelines

1. The design drawings specify a winding coefficient (n=1, 2?), commonly used for large-diameter pipelines.

2. The method is as follows:

* The electric heating cable is laid from one end of the pipeline to the other end and then back to the starting point, the number of times equal to the coefficient.

* The electric heating cable is laid alternately from one end of the pipeline to the other end, the number of times equal to the coefficient.

* A backup system is used for critical pipelines in emergency situations. Therefore, each line should be an independent line device.