Application #2: Multi-track PID control in the process of soaking welded elements

Application example of multi-channel controller Multicon CMC in pipeline preparation process before welding

The MultiCon controller features 8 PID controllers and each of them can have different settings. Moreover, one controller with prepared settings can be used in many independent processes. An example of such an application is the pipeline preparation process before welding, so called PWHT (post weld heat treatment). The pipeline gets covered with six heating mats that work independently, heating the entire pipeline up to the proper temperature.

The application works with the CMC-99-PS42/USB/S8/E/TC8-001 model.

Signal inputs

The TC8 module consists of 8 thermocouple inputs (J, K, S, T, N, R, B, E (PN-EN); L (GOST); ± 25mV, ± 100mV, -10 ÷ 25mV, -10 ÷ 100mV ). Thermocouples mounted on the surface of the pipeline are connected to six of them.

The S8 module consists of 8 SSR outputs that regulate the temperature of the heating mats.

Configuration

One PID controller was adapted to the process. The controller settings are selected by the auto-tuning function. The device, based on measured temperature values, implements simultaneous, independent control of six processes. Each of them is temperature regulation of a specific heating mat. Therefore, one of the controllers is used here six times at the same time.