A Measurement and QCS Systems.
Jasch develop and manufacture measurement and control systems to improve the quality of production on paper machines and bring cost reduction and productivity increase to operations.
Jasch systems continuously monitor and control the quality parameters such as Basis weight, Moisture, Ash, Caliper & Coating thickness etc. The deviations from preset target values are instantly detected allowing immediate corrections to the production process to maintain constant product quality. All relevant measuring results are evaluated and displayed graphically on a monitor and documented by hard copy.
More than 100 systems installed worldwide are impressive evidence of the market acceptance and capability of our products and services.
The modern Quality Control Systems (QCS) for pulp, paper, tissue & paperboard industry, designed to be flexible and with open software architecture without compromising on system reliability, availability and ease of maintenance: Jasch pulp & paper gauge BTG-3000 PP system fulfils all these needs using the latest in electronic technology and proven heavy duty mechanical components.
The system is designed to concentrate on the most important task of accurate and stable measurements of the paper parameters. The sensors are mounted on a high precision scanner platform which carries the sensors and scans across the paper web continuously. The scanner has all the function control and signal conversion/processing electronics included in a side panel. All measurement data from scanner is sent digitally via RS485 link to a PC based system which processes all measurements, generate profiles, implements calibration tools, service & maintenance and machine/process control.
The Operator interface is implemented on another PC based system which is connected to the processing system through Ethernet link. The Operator interface is based on Labview™ which is highly user customizable and adaptable to varying mill requirements. Comprehensive production reports are generated for storage and hard copy.
The whole set of profiles and measurement & control parameters from the processing system are available through an OPC server for mill wide access.
The basic paper gauge BTG3000 PP quality control systems (QCS) provides Machine Direction control of Basis weight, Moisture and Ash content in paper. For multilayer machines, the control is provided by calculated dry weight for each individual layer. In addition with co-operation partners, The system can provide Cross direction control of basis weight, moisture and caliper.
For all pulp & paper machines the basic measurement required is the Basis Weight of the paper. The measurement is displayed as GSM (or g/m2) which is the basic parameter the operators use to ensure that their production is always with in the acceptable weight range. The measuring principle is based on the attenuation of Beta radiation emitted by a nuclear source as it passes through a material. The basis weight is determined by sensing variations in the energy radiated by the source of known intensity.
The next most important measurement is the Moisture measurement. This measurement enables the machine operators to keep the water content in the paper with in acceptable limits and is especially useful for optimizing the production capacity. There are two types of moisture sensors based on Infra-red (IR) or the Microwave radiation.
IR sensor is most suitable for fine paper and lighter paper grades. For paper up to 250 GSM, the IR sensor is used in the transmission mode. For higher range, the single sided backscatter sensor has to be used as IR radiation can not pass through the paper. The transmission sensor measures the bulk moisture of the paper and the backscatter type measures only the surface moisture in paper by reflection. The measurement is based on the principle that when infrared light passes through or is reflected by a paper sheet, it is preferentially absorbed at very specific wavelengths by the water in the sheet, more so than fibber or other sheet components.
The Scanpro™ microwave moisture sensor is most suitable where GSM of paper is higher then 250 GSM and bulk moisture measurement is required or where there is high carbon black content in paper. The sensor is commonly used for multi-ply products such as boxboard and corrugated cardboard. The measurement is based on resonant absorption of microwave radiation by water.
The other two important measurements are Ash contents and Caliper.
The Ash measurement is based on the principle that X-ray radiations are absorbed preferentially by the inorganic material in a paper sheet. As Ash contents increases, transmitted radiations that are captured by the ion chamber type detector is reduced. Ash content is calibrated for sheets containing Clay, Calcium Carbonate & Titanium Dioxide. Calisens™ is a non-contacting Caliper sensor. The sensing heads ride on the moving sheet without any friction on air bearings of special patented design maintaining an ultra stable cushion gap thickness thus providing accuracy level of that of contacting sensors but without their problems.
The scanning platform (O-Frame) carries all the sensors required by the customer and continuously scans back and forth across the paper sheet being measured. The sensor carriage is continuously moving, and throughout its scan the source and detector parts of the sensors must remain aligned. Scanner precision and stability are crucial for obtaining proper measurements from the sensors. The O-Frame Scanner is designed to be very strong, reliable and at the same time accurate. The design is based on double I-Beam structure welded together to form a box construction. The resulting O-Frame structure is very strong, rigid and mechanically stable. It is only with this rigid structure that makes it possible to mount transmission sensors and maintain high precision alignment during scanning back and forth across the paper sheet. During the manufacturing process the top and bottom sensor carriages are precisely aligned to within ± 0.5mm in x, y and z directions. The materials used are chosen for precision and reliability under heavy duty daily use. With the rigid O-Frame design this precision alignment is mechanically locked into system. The carriage mo movement is on heavy duty linear motion system based on ball bearings with many times over rating.
Paper Gauge and Paper QCS (Quality Control Systems).