Fornos elétricos

PID temperature controller for aluminium furnace AMS2750 conformant

Find out how to get the most accurate temperature readings from AMS2750 certified aluminium furnaces

Produtos relacionados

3850T
Up to 16 PID loops Controller Programmer and Recorder, 7” graphic touch interface
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Indicador/Limite do alarme de segurança (FM)
2850T
Up to 8 PID loops Controller Programmer and Recorder, 3.5” graphic touch interface
GPC
Single/Two/Three phase Advanced Power Controller up to 600A

Control and temperature values reading of aluminum furnaces

2850T and 3850T multifunction PID controllers fully meet the requirement of AMS2750 precise and uniform temperature control and encrypted batch data recording:

  • precise PID temperature control and thermal profile generation;
  • batch data recording ;
  • ethernet connectivity with Factory Control System.

Overview

  • Application: Data Recording and temperature control of aluminium furnace AMS2750 conformant.
  • Product: 2850T PID controller, 3850T data recorder, 650L High limit controller, GPC Power Controller
  • Result: AMS2750 temperature accuracy, Batch data recording, Ethernet/IP connectivity with Rockwell PLC

The process

In aeronautical industry, most of the structural components of an aircraft are made of aluminium alloys. Their corrosion resistance, mechanical strength and lightness allows significant loads to be carried at a low weight. Thermal treatments of Annealing and hardening are used to achieve the different mechanical characteristics required for a specific application.
Annealing improves the ductility/deformability characteristics of the component, which is useful for subsequent bending/forming operations. The material is heated to 400°C (752°F) with a gradient depending on thickness and held for several hours (up to 20), then slowly cooled to room temperature.
Hardening is a heat treatment that increases the hardness of the product and is normally carried out at 350°C (660°F). This process temperature can be held from several hours to several days, depending on the technical properties required.

Figure 1 – Temperature control scheme

The challenge

Temperature accuracy and uniformity

Heat treatments in the aircraft industry are subject to AMS2750 procedures that guarantee the process. High accuracy of the temperature reading (±2 °F / ±1.1 °C or 0.2% of reading) and temperature uniformity inside the oven are some of the characteristics required of the control instrumentation. The ability to read 3 temperature probes, in order to calculate the average control value used by the PID controller is useful to guarantee a uniform process temperature.

Batch data recording

To confirm the correct heat treatment, the temperature values for each production batch must be recorded and stored in a protected (encrypted) format.

Fieldbus connection

Heat treatment furnaces, like all automation system modules, are controlled by PLC with an Ethernet/IP connection. The ability of using different Ethernet-based communication protocols (e.g. Modbus TCP) within an Ethernet/IP fieldbus network made possible to integrate different control devices.

Products benefits

Multifunction PID controller 2850T/3850T

  • Precise multiloop PID controller (up to 16 loops) with self and auto tuning
  • User friendly for operator’s graphic display, process mimics, local visualization.
  • Control, Recording and Alarms embedded graphic pages.
  • Encrypted batch data recording with CSV or PDF export file
  • Logic and math function block
  • Connectivity: Ethernet Modbus TCP/IP and VNC remote access.

GPC three phase Power Controller

  • Current ranges from 30A to 600A, 1-2-3 phase, 690Vac
  • Command mode: configurable
  • Heater breakage alarm with self-learning
  • Connectivity: all the most commonly used Ethernet field buses

650L overtemperature safety threshold

  • System safety overtemperature alarm relay
  • Factory Mutual Certificate (FM)

Solution

2850T and 3850T multifunction PID controllers fully meets the requirement of AMS2750 precise and uniform temperature control and encrypted batch data recording.

Temperature control and temperature profile generation

  • Furnace temperature PID closed loop control
  • Temperature reading accuracy according to AMS2750 in the aeronautical industry (Fig.3)
  • Control of furnace temperature uniformity with calculation of average value, between 3 temperature values, used as SP reference
  • Connection with PLC (Modbus TCP – Ethernet/IP) and automation system integration
Figure 3 – Temperature reading accuracy

 

Batch data recording

  • Recording of process temperatures for ensuring oven temperature uniformity (Figure 2) with reference to batch number
  • Secure data storage in encrypted format
  • Remote backup of archived data via Ethernet
  • Local and remote viewing of logged data
  • Automatic date/time synchronization with SNTP service
Figure 2 – Batch data recording

650L over temperature limit switch

  • FM (factory mutual) certification
  • Dedicated front key for alarm reset (ACK)
  • Total alarm activation time and count

Electrical heating over gas fired furnace

Control of electric heating resistors during the soaking phase as an alternative to gas burners heating. In this phase, which can last from several hours to several days, electric heating was preferred for better energy efficiency.

GPC three phase Power controller

  • Ethernet/IP connection to PLC system for control and diagnostics communication
  • ODVA Ethernet/IP certification
  • Partial load failure diagnostics (Fig.4)
  • Compliance with SCCR UL 508 100KA
Figure 4 – Partial load failure (HB alarm)