Forging Temperature Measurement – All Metals

Temperature Control for Forging Plants

The forging industry has a broad range of manufacturing processes, making many different types of products. Aluminum, copper, steel and titanium are the most popular metals that are used in the forging process. While there are a number of different ways to forge metal, the process essentially remains the same. It requires heating a piece of metal and then deforming that metal into a particular shape. Temperature control for forging parts is critical in achieving the desired metallurgical and structural properties. The two most essential forging measurements are the billet and die temperature measurement.

Williamson Wavelength Technologies

Billet: For the measurement of aluminum multi-wavelength (MW) models are preferred due to significant non-greybody emissivity variation. SW technology is preferred inside a flame-fired furnace, but otherwise, MW technology is preferred. MW technology provides an ESP algorithm to compensate for non-greybody emissivity variation associated with copper and aluminum.

Die: Williamson offers two technologies for the measure of die temperature. The SW-16 wavelength set views clearly through flames and is preferred for static preheating processes. DW models are best when measuring dies that are in constant motion. DW models are equipped with unique ESP Filtering, used to recognize valid measurement conditions. Signal Strength and Signal Dilution filters enable the sensor to make a continuous die temperature reading while ignoring flames, lubricant spray, workpiece temperature, and closed die temperature.

Download the Complete Set of Iron & Steel Forging Application Notes

Steel/Titanium Billets

Application Overview

For steel and titanium, the billet temperature is raised to make the metal softer and more easily deformed. Overheating the billet can cause surface defects and requires extra lubrication to prevent sticking to molds and dies. Under-heating can cause cracking and excessive die or mold wear. Clearly, precise billet temperature measurement is an important part of the steel and titanium metal forming process.

Williamson Wavelength Advantage

SW pyrometers are affected by emissivity variation, optical obstruction, and misalignment. Two-color (TC) pyrometers are affected by surface scale. Williamson DW pyrometers accurately compensate for emissivty variation, optical obstruction, and misalignment, and are 20 times less sensitive to scale.

Pyrometer Benefits
  • Assure desired product properties
  • Eliminate cracking and surface blemishes
  • Avoids die and mold wear
  • Minimize lubrication
Wavelength Technology
  • DW pyrometers are 20x less sensitive to scale compared to SW and TC technologies
  • DW compensates for emissivity variation, optical obstruction, and misalignment

Static Die Temperature

Application Overview

During the forming process, die temperature influences the temperature of the surface of the workpiece and this can affect product quality. Hot dies require extra lubrication and can cause sticking and surface blemishes. Cool dies require extra lubrication and can inhibit flow and cause cracking or hardening of the workpiece.

Contact thermocouples are influenced by the temperature of the air, any wind currents, and the amount of pressure applied to the die. Infrared pyrometers provide a more accurate and more reliable measure of die temperature.

For some metal forming plants the process cycle is slow and for others it is fast. For plants that are able to easily obtain a temperature value from a relatively static die surface, the short wavelength technology is recommended.

Williamson Wavelength Advantage

Using short-wavelength technology the Williamson SW is less sensitive to emissivity variation and optical obstructions compared to longer wavelength sensors. The thoughtful wavelength selection of the SW-16 and SW-22 models allows for the sensor to view clearly through flames.

Pyrometer Benefits
  • Improved surface conditions
  • Improved metal flow and shape
  • Lower lubricant needs
  • Consistent product quality
Wavelength Technology
  • Short-Wavelength technology reduces sensitivity to emissivity variation, optical obstruction, and misalignment.
  • The SW-16 and SW-22 wavelength sets tolerate steam, oil, and flames without interference.

Dynamic Die Temperature

Application Overview

During the forming process, die temperature influences the temperature of the surface of the workpiece and this can affect product quality. Hot dies require extra lubrication and can cause sticking and surface blemishes. Cool dies require extra lubrication and can inhibit flow and cause cracking or hardening of the workpiece.

Contact thermocouples are influenced by the temperature of the air, any wind currents, and the amount of pressure applied to the die. Infrared pyrometers provide a more accurate and more reliable measure of die temperature.

For some metal forming plants the process cycle is slow and for others it is fast. For plants where the die is rapidly opening and closing, the dual-wavelength technology is preferred because of the ability to automatically recognize valid measurement conditions.

Williamson Wavelength Advantage

Because of a greater separation between wavelengths, the DW technology will read hottest temperature within the field of view. This allows the sensor to eliminate inaccurate reading from emissivity variation, optical obstruction, and misalignment. The DW technology also includes ESP Filtering which is used to recognize valid temperature conditions and ignore interferences.

Pyrometer Benefits
  • Improved surface conditions
  • Improved metal flow and shape
  • Lower lubricant needs
  • Consistent product quality
Wavelength Technology
  • Dual-wavelength technology compensates for emissivity variation, optical obstruction, and misalignment.
  • Tolerates oil, steam and flames without interference.
  • ESP filtering recognizes valid conditions permitting the pyrometer to measure only when viewing the exposed die surface

Consult With One of Williamson’s Temperature Experts

We would love to discuss your temperature measurement application with you.

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