The MCT-360 series is routinely used in various converting applications to make a moisture measurement on a continuous basis, normally over a moving web. This measurement can be converted to a coat weight measurement, if the coating is applied as a function of a water carrier.
So, a gauge located on the wet end of a process can be used to determine finished coat weight in whatever engineering units are used by the converter. The critical element in this sort of measurement scheme is that the solids/liquid ratio of the applied coating is constant.
Chromate Conversion Coatings have traditionally been applied to electro-galvanized steel and aluminum alloy surfaces to render them corrosive resistant, and to establish an adhesive base for organic coatings in the early stages of the coil coating process. Chromium VI, hexavalent chromium has been the most predominantly used form, but its usage is being curtailed through RoSH legislation owing to its toxicity. Chromium III is safe to use, and is still being used by many aluminum manufacturers but recently, newer alternatives based upon titanium, zirconium, cerium and cerium molybdenum systems have been introduced.
Control of coat weight and coverage is important as it impacts the physical and chemical properties of the sheet metal. The surface film is formed by a chemical reaction so it effectively becomes an integral part of the metal surface. Provided the film is continuous, the metal sheet can be molded without adhesive failure of paint, lacquer or powdered coatings that are applied further down the coil coating line.
Application process and measurement location
The aqueous based coatings can be applied in a number of ways; via a roll coater, brushes or spray nozzles.
Water is an excellent absorber of NIR so measurement is made at the ?wet end? shortly after the tensioned metal sheet has left the metal roller with the water based coating applied. As coating is applied to both front and back of the metal sheet, a gauge is typically mounted either in a fixed position or on a scanning frame either side of the web, the scanning option will obviously provide a better indication of the total coverage. The MCT 360 is calibrated against the dry coat weight value and is extremely accurate providing the solids ratio remains constant; gauge readout is continuous, updating every 90ms. The data enables manual or automatic adjustment of the coater through the MCT Controller Output. This could be implemented through a change of speed and/or pressure of the rollers, or pressure in the case of the spray nozzle.
Typical measurement performance: 0.05 ? 0.1 mg m-2 over the range of 3 ? 8 mg m-2 dry coat weight.
Example: Titanium based granodine coating.
The calibration and trend plot below relate to 9 samples that were taken from production. In this example dry coat weight range was between 3.4 and 6.5 mg m-2
Process Sensors will be exhibiting at the PackExpo at McCormick Place, Chicago, IL on Oct. 31-Nov 3rd. Featured products will be the MCT360 measuring moisture, coat weight, film thickness and temperature by using on-line near infrared technology. It gives instant, continual readings as product pass beneath its light beam. Also featured will be our Automatic Scanning Frame that continuously moves the transmitter across a moving web. Proprietary PSC software can then create a cross web profile for moisture, coat weight or film thickness in real time.
Process Sensors has become the leading manufacturer of on-line NIR moisture meters. Moisture analysis is critical throughout many stages in the processing industry. Manufacturers are constantly adjusting moisture to maintain the quality of their product. If the product is too wet or too dry, the quality of the product can create problems later in the manufacturing process.
Moisture analysis is used for a variety of applications such as, moisture in tobacco, moisture in food, moisture in snack food, moisture in paper and moisture in particleboard.
Moisture in Snack Food
The continuous measurement of moisture prior to packaging is a key consideration in the production of snack foods. The proper moisture content helps guarantee taste, texture and shelf life.
The use of NIR (Near Infrared Reflection) moisture meters in snack food manufacturing environments has become an accepted technology for monitoring and control. The on-line measurements are instantaneous and non-contact. Any change in moisture level can be immediately recognized by the use of a process controller, eliminating the potential for customer quality complaints or waste.
Moisture in Particle Board
The proper moisture level of particleboard guarantees safety and high product quality.
During the drying phase, the moisture content is reduced from a high of 75% to less than 10% moisture. The dried material is then graded and separated into core and surface product. The products pass through different blenders as a function of their different requirements for resin. After the blender, the furnish is formed then pressed into boards.
Paper Converting Process
Continuously monitoring the level of moisture in paper is important. The proper moisture level can have a large impact on the curl properties of the paper. By installing the MCT Moisture Meter in line, a converter can continuously monitor the moisture level and manually or automatically control the moisture content across the paper web.
Moisture percentage is critical throughout the whole tobacco manufacturing process, from green leaf threshing to primary processing. Moisture affects not only smoking quality, but also storage properties, filling properties, tobacco waste and machine ability.
Process Sensors MCT Series moisture meters, employ true Smart Sensor Technology (SST?), next generation optics and stable electronics, to meet the increasingly stringent quality controls required by today’s manufacturing industries, and to provide innovative process control solutions for maximum on-line manufacturing productivity, cost efficiency and profitability. PSC?s moisture meters have all field-replaceable components and come with a comprehensive 2-Year Warranty.
Process Sensors NIR Moisture Meters can provide valuable information needed to control the production process. The result is consistent product produced at minimum cost and down time.
Moisture measurement is a major consideration throughout the pellet manufacturing process. Below ware some of the locations where our customers have used our meters.
1. PSC can measure the green product prior to the dryer. The main advantage is to aid the loader operator in balancing the input moisture load to the dryer. Green product is generally stored outside where it is subject to the environment, some is wet and some is dry. Large amounts of wet material can overload the dryer and moist sawdust is the result. The loader operator needs a large readout at the input hopper so he/she can properly select wet or dry material to balance the input moisture.
2. Measuring the output of the dryer provides quality control on the dryer output and allows the product to be binned by moisture content.
3. Measure the output of individual bins for accurate blending.
4. Most important is the moisture in the blended product as it enters the pellet press. It must be within a tight moisture range to produce an acceptable pellet. The instantaneous reading are very helpful to the Press Operator. The 4-20 mA output can be sent to a PLC which in turn can control the Pellet Press drive parameters in real time.
5. Laboratory or off line measurements can be made in 10 seconds with the MCT660.
6. Some mills use Hog Fuel for the boiler feed, our MCT360 offers good trend moisture measurements on the incoming Hog Fuel. The advantage is improved boiler control.
STAND ALONE, IR THERMOMETER?S DUAL LASERS, MAKE FOCUSING AND TARGET SIZE DETERMINATION EASY.
Knowing the precise point or area of a target to be monitored when using infrared thermometers for temperature measurement is critical to measurement accuracy. Process Sensors? newly released model PSC-CS-Laser thermometer series eliminates guesswork by using two, built-in, bright red lasers.
At the focus distance, the laser beams converge to form a single spot on the target. At distances other than the focus length, individual laser spots delineate the measured target size diameter. The model PSC-CS-Laser series are self contained pyrometers constructed from rugged stainless steel that can be configured for 2 wire loop powered or 4 wire operation when utilizing dual lasers for targeting.
The high accuracy infrared temperature sensor can operate in ambient temperatures up to 185?F (85?C) without the need for cooling, offers fast speed of response and high resolution optics with selectable fixed focus distances for small target sizes from 0.020? (0.5mm) in diameter. The rugged stainless steel housing with companion heavy duty cooling jacket with air purge, stands up to the most severe industrial environments.
Spectral responses of 8 to 14? with a temperature range of -50 to 975?C, or 1.6? with a temperature range of 385 to 1600?C, suit the loop powered, compact sensors to a wide range of applications such as induction heating, metal processing, semiconductors, paper, plastics, webs, ovens, furnaces, glass, ceramics, thermoforming, food, powders, liquids, hot material /aggregate on conveyors etc. Outputs are analog 4 to 20mA, 0-30V open collector, used for alarm and digital uni/bidirectional, 9.6kBaud, communication.
Measurement parameters such as emissivity can be set manually on the IR sensor, or via PSC Connect software with optional USB connector. The software also facilitates the set-up of peak, valley and averaging functions, graphic display of temperature trends, and data logging with a 1ms response time.
Detailed specification information is posted at www.processsensorsIR.com.
Process Sensors is a private company with a manufacturing facility located in Milford, MA, USA. The company is a manufacturer and distributor of non-contact temperature and moisture measurement instruments, and the associated calibration systems. The Company provides technical and application support worldwide through direct, regional and sales representative offices.
The response speed of the fastest infrared thermometers until now has been limited to the millisecond domain. Process Sensors newly released, self contained, Metis HS09/HI16 non-contact infrared temperature sensor captures 20,000 measurements per second with an unprecedented 50 microsecond response.
With a temperature span of 250?C to 2500?C, over three models, the HS/HI Series opens up applications in high speed ferrous and non-ferrous metals processing, ceramics, semiconductor and in research environments where short duration phenomena such as explosions must be monitored. Target spot sizes of 0.35mm to 4000mm dia. are offered over the same three models, using standard, focusable optics; or 0.5mm to 40mm with focusable lens fiber optics.
Other notable features include laser aiming and through lens sighting, and an integral black and white video camera for monitoring the target area in hazardous or hard to access locations. A peak picker function can be set up to detect and hold the highest measurement in applications where the target is intermittently obscured by steam, dust or surface scale.
Switchable, analog 0 to 20mA /4 to 20mA outputs connect with process control or data acquisition equipment. A fast, digital, RS485, 921 kBd maximum communications interface is also included. IR Thermometer parameters can be set up using Process Sensors free PSCWin software. The software also facilitates the recording of data in graphical, text or tabular format.
Detailed specification information can be found at www.processsensorsir.com
Process Sensors is a private company with a manufacturing facility located in Milford, MA, USA. The company is a manufacturer and distributor of non-contact temperature and moisture measurement instruments, and the associated calibration systems. Technical and application support is provided worldwide through direct, regional and sales representative offices.
The continuous measurement of moisture is a key consideration in the production of particleboard. The proper moisture level of particleboard guarantees safety and high product quality.
Particleboard Production Process
Raw materials are passed through chippers, flakers and size reduction mills to create a relatively uniform particle size. The mix passes through screeners which remove fines, before they enter the dryer. During the drying phase, the moisture content is reduced from a high of 75% to less than 10% moisture. The dried material is then graded and separated into core and surface product. The products pass through different blenders as a function of their different requirements for resin. After the blender, the furnish is formed then pressed into boards.
Measurement Location and Installation
Measurements can be made at five different location; on the raw material, pre-dryer, post dryer, post blender and on the former. The sensor can be positioned to look through a viewing window at a 15? angle in the side of a storage bin of gravity chute. The sensor can also be positioned over a conveyor/weigh belt, or on the side of a formed mat. Whatever the location the moisture sensor should be mounted approximately 200cm from the product. The most common location for a moisture sensor is over the forming line.
Process Sensors Corporations significant design innovations and installation simplicity combined with formidable industrial packaging allows for seamless integration into existing systems. The new DT-44G and DT-44GH line of digital, self-contained, non-contact infrared temperature sensors are exceptional performers in glass and solar cell production applications for measurement of glass surfaces and substrate materials. They have also proven to be equally beneficial in the ceramics and semiconductor industries.
High speed, accuracy and repeatability, along with 4-20mA output RS485 interface capability, make the Model DT-44G and high-speed version DT-44GH the instruments of choice for system integrators, OEM’s and engineering companies. The DT-44G response time is 30ms, and the DT-44GH boasts a 10ms response.
An integrated green LED aiming light facilitates pin-point target alignment. The projected size of the LED is identical to the measuring spot and is clearly visible on hot targets. Alternatively, the Models DT-44G and high-speed DT-44GH can be equipped with a red laser.
The DT-44 series offers three temperature range choices (100 to 1300?C, 200 to 1400?C, and 500 to 2500?C) and features USB interface that makes adjustment of all sensor parameters easily accessible via PC, with optional software and connecting cable up to 30m long.
The robust stainless steel housing and cooling jacket with air purge stand up to the most severe industrial conditions and ensure consistent sensor operation regardless of environmental hostility.
Process Sensors Corporation is a company totally dedicated to customer support. Experienced infrared application specialists provide unique sensor solutions for a myriad of temperature measurement applications. The company continuously endeavors to combine product training, installation guidance assistance, and ongoing technical and commercial support to effectively address customers needs.
The continuous measurement of moisture in the paper converting process is a key consideration. The proper moisture level can have a large impact on the curl properties of the paper. By installing the MCT Moisture Transmitter in line, a converter can continuously monitor the moisture level and manually or automatically control the moisture content.
The Transmitter is routinely used to measure finished moisture prior to wind up. It is also used for measurement and control of water addition by various means: spray addition, steam, rolls, and knives. The location is dependent to a large degree on the availability of space on the converting machinery. The location is also determined by the requirements of the control strategy. PSC can make the appropriate suggestions on proper location upon discussion. The Transmitter should be mounted about 12 from the web. This distance can be optimized for machine limitations. If the paper is glossy or wet the Transmitter should be angled about 15 degrees off of the perpendicular, relative to the web. It is important to keep environmental temperature in mind. If the Transmitter is used in close proximity to a dryer outlet or heater, cooling may be required. Air or watercooling devices, supplied by PSC, can be used for cooling. An air purge assembly over the optical window may be required, especially if the environment is steamy enough to cause condensation on the window.
Moisture in paper is a very well understood and documented application.
Measurement wavelengths, algorithms, and sensor optical parameters are pre-set at the PSC factory. Calibrations are also pre-set at the factory. Typical accuracy is about ?0.2% moisture. It is possible to improve that with careful sample handling and lab methodology. Very different basis weights can require different calibration settings. The same is true for dramatic color differences. PSC can advise. Typical analog output range is 0-10% moisture. The Transmitters output range can easily be adjusted for the best PLC or controller operation. Process Sensors is very experienced with the requirements of this application.