High-speed fibre-optic ratio pyrometer

Dr Mergenthaler high-speed quotient pyrometers are ideal tools for measuring temperatures on metals and many other surfaces. One advantage of two-colour pyrometers is that temperature measurements are largely independent of the surface’s emissivity. Furthermore, unlike infrared pyrometers, the measurement spot can be smaller than the pyrometer’s spot size.
Two-colour pyrometers can also be switched to operate as infrared (single-colour) pyrometers via software. All Mergenthaler pyrometers are supported by the same software, LASCON Process Manager. This creates a complete system comprising high-speed temperature data acquisition, visualisation, real-time storage and archiving.

Typical temperature ranges for Mergenthaler quotient pyrometers (2-colour pyrometers):

from 300°C to 2400°C across various measurement ranges (at 10,000 measurements per second)
For example: 300°C to 1,000°C, 550°C to 2,300°C

Even with unknown emissivity coefficients, quotient pyrometers measure temperatures accurately on many surfaces.

Application:

• Laser hardening
• Laser cladding
• Laser welding
• High-temperature processes

The integrated temperature process controller can be used to control laser sources or induction generators. This makes it easy to optimise the quality of processes that were previously carried out under controlled conditions by specifying a processing temperature.

The system operates autonomously: this means it measures, controls and stores data at a rate of up to 15 kHz without a PC connection. With the LASCON® Process Manager software package, you can visualise , configure and monitor your laser process. Using a simple scripting language, up to 256 different laser scripts can be programmed and executed. These scripts enable you to monitor your laser processes 100 per cent and ensuretraceability across your entire production.

• Over 2,300 units sold in industry and research
• 10,000 (optionally 15,000) temperature measurements per second
• The ratio pyrometer can also be switched to infrared pyrometer (single-colour pyrometer) mode via software
• Infrared measurement range from 180°C, ratio pyrometer from 300°C
• Grayness adjustable via software to adapt to various surfaces
• Available in various measurement ranges up to typically 3,000°C
• Fibre-optic cable length up to 40 m, measurement spot up to 0.3 mm
• Suitable for all diode lasers (808 nm, 940 nm, 980 nm), Nd:YAG 1064 nm, CO₂ 10.6 µm ...
• Visible pilot beam, dimmable
• Store up to 500,000 processes in real time on an integrated flash drive
• Monitor processes with simple script programming
• Create and activate 255 different process scripts
• Temperature and power monitoring trigger pass/fail signals
• 24V industrial I/O interface (Start, Stop, Ready, Active, Script Select, process error...)
• Analogue In/Out
• Ethernet interface
• Analogue output 0–10 V (0–5 V) for controlling lasers, heating elements and inductors
• Remote On/Off
• 24V power supply, optional wide-range power supply 90–260 VAC
• Self-monitoring and device diagnostics

With over 1,500 industrial LASCON installations worldwide, Mergenthaler is the global market leader in temperature-controlled laser material processing.

Applications for Mergenthaler LASCON quotient pyrometers include:

• Laser cladding: measuring the temperature of the powder deposit to achieve a constant and homogeneousweld bead width. In a controlled process, the slow heating of the workpiece during the process gradually results in an ever-wider weld track. This undesirable effect is counteracted by temperature control.
• Laser welding: Temperature-controlledlaser welding of, for example, aluminium and aluminium/steel composite materials is an example of applications for LASCON in the laser welding of metals.
• Laser hardening: A temperature-controlled laser hardening process is now standard practice. Laser control using a pyrometer compensates for the varying absorption behaviour across the workpiece, as well as for the differing heat dissipation through holes beneath the surface or edge effects. Mergenthaler LASCON systems with quotient pyrometers have been used worldwide for more than 15 years to control the temperature during laser hardening.
• Tempering following laser hardening or welding to relieve residual stresses