Increasing production speeds and the requirement for lighter products in the glass industry have emphasized the need for more effective control over the forming process to obtain greater control of the dimensional variants of the end product.The measurement of the mold temperatures can be used to control the cooling air plunger temperature, dwell time, and pressing pressure.The effective control of the heat transfer can regulate the application of the lubricants and determine their functions more accurately.
The rate at which glass and more particularly the surface layer of the glass are cooled while in contact with the forming mold is of great importance in the manufacture of glass containers and pressed ware. Until recently,the difficulty in measuring the transient temperature changes in the actual forming operations has limited both the understanding and the control of the heat transfer.
Thermocouples of very fine diameter have been embedded in the glass temperatures , but the interpretation of such measurements in a material such as glass with repidly varying temperature gradients within it is quite difficult.
To provide temperature measurement solutions by infrared technique Portable Glass Mould Thermometer was introduced. P-GM is a hand held, battery powered thermometer designed primarily for the measurement of mould temperatures in container glass industry.It gives an instantaneous reading of the temperature with the press of a single switch. Readings taken are stored into memory and logged with serial number and date/time for review later. Stored temperature readings are held in memory until is turned off or the battery is removed. It provides a powerful data logging capability with storage for up to 1000 measurements.PGM comprises a hand held thermometer with integrated display unit. Probe head collects the infrared energy emitted by the mould and transmit to the sensor assembly in the probe handle via a rugged mono fiber encapsulated in 300mm long Stainless Steel protection tube. Probe head has 90°C,45 ° or straight angle for easy accessibility to the mould.
In PGM processor converts the signal to temperature and display in the LED display. The entire process is completed within 2ms which ensure measurement of mould in fast operation. Temperature measurement can be taken either by contact or by non-contact method. The probe tip is designed in such way which eliminates the reflection of the mould. Sensor working in 1.6micron ensures highest accuracy and low effect of emissivity changes.
The probe tip is field replaceable . The instrument is powered by 4AAA size rechargeable cells with inbuilt recharging facility.
Advantages of PGM
1. Fast and easy measurement of blank and blow mold temperatures.
2. Measurement by non-contact method.
3. Automatic temperature measurement.
4. Recording of 1000 measured data.
5. Usable replaceable fiber cable and optical head.
6. Field re-calibration software.