Structure configuration of paper machine

- Oct 20, 2020-

Structure configuration of paper machine
    (1) Headbox
    Crescent-shaped hydraulic headbox, composed of frame and adjustment system, tapered pipe slurry distribution, orifice plate, balance chamber, turbulence generator, flare, adjustable upper and lower plate, worm wheel and worm full width adjustment, etc. .
    (2) Crescent paper machine Former
    Four-roller cantilever type. The four rollers are breast roller, separation roller, tension roller and correction roller. The frame is a box steel welded structure, and the longitudinal and cross beams and the frame base are all covered with stainless steel. Cantilever design. When changing the forming fabric mesh, the operating side frame is opened and lifted by a hydraulic jack. The frame structure is opened for easy screen changing. Equipped with 1 set of automatic corrector and correction valve, 1 set of automatic tensioner, 1 set of chest roller expansion device, 4 sets of scrapers, high and low pressure spray pipes, etc.
    The allowable elongation of the forming net is 1.5%, the maximum tension is 10kN/m, the net tension is detected by the tension sensor, and the tension signal is fed back to the tensioner through the PLC to automatically tighten the net; at the same time, the tensioner has 2 limit switches, to It stops after limit and can only run in reverse.
    The water collection device is the design focus of the crescent shaper. The drip tray under the net receives the white water coming off the forming roller, and is equipped with a curved deflector. The rollers are equipped with a water receiving pan to collect the white water taken off by the scraper. There are baffles around the net, water mist splash baffles are installed on the transmission side and the operation side, and the baffles on the operation side are movable.
    (3) Felt department
    The frame is a box steel welded structure, and the longitudinal and cross beams and the frame base are all covered with stainless steel. Cantilever design, when changing the fabric screen, the operating side frame is opened and lifted by hydraulic jack, the frame structure is opened, which is convenient for changing the felt. Equipped with 1 set of forming rolls, 1 set of vacuum rollers, 6 sets of blanket rolls, 2 sets of felt suction boxes, 1 set of automatic corrector and correction valve, 1 set of automatic tensioner, 3 sets of scrapers, high and low pressure spray pipes, etc. .
    The solid forming roll is the feature that distinguishes the Crescent Toilet Paper Machine from other types of paper machines. It does not need to be vacuumed, and it is naturally dehydrated by the centrifugal force of the forming roll, and the power consumption is small. The roller body is made of Q345 steel plate, internally and externally processed; the shaft head is 45# steel quenched and tempered, the bearing is matched with a 1:12 cone; the covering material is hard rubber, and the rubber hardness is P&J0o.
    The encapsulation of vacuum roller is special rubber for high-speed toilet paper machine. The rubber hardness is P&J24o. It is designed with blind holes and the total opening rate exceeds 30%. The single-chamber vacuum box is made of 316 stainless steel, and the angle of the vacuum chamber is 140o. The seal is imported graphite sealing strip. The vacuum roller is designed to have a line pressure of 100kN/m. In order to ensure the stability, synchronization and accuracy of the line pressure under high-speed operation, the pressure device adopts hydraulic pressure, equipped with hydraulic cylinders, hydraulic stations, and hydraulic systems linked to the transmission system. The main components of the system and hydraulic system are imported products.
    The box body of the blanket suction box is 304 stainless steel with a thickness of 6mm. After the box body is welded, the internal stress is eliminated. The panel is a full ceramic zirconia panel with a life span of up to 3 years.
    (4) Yankee cylinder
    The Yankee cylinder has a diameter of φ3660mm and a design pressure of 0.8MPa; it is designed and manufactured in accordance with ASME standards while meeting my country's industry standards to ensure safety and reliability. The cylinder body is alloy cast iron HT350, and the end cover is cast iron HT350; the shaft head and the center tube are integrated design, and the material is ductile iron QT400. In order to obtain high heat transfer efficiency and cylinder surface temperature, a new type of spoiler and siphon system is installed in the cylinder (Figure 1). This system is a patented product, which not only improves the heat transfer efficiency of the dryer, saves steam consumption, but also facilitates the removal of condensate. At the same time, both the operating side and the transmission side shaft heads are equipped with heat insulation sleeves and rotary joints.

Figure 1 Axonometric view of new spoiler rod and siphon system
    In order to further save steam, the Yankee cylinder also specially designed a radiation-proof end cover insulation board, which is also a patented product.


(5) Yankee cover
    The Yankee hood is a steam-type high-speed hot-air hood, all stainless steel structure, divided into a dry half hood and a wet half hood, the two parts can be opened. The inside is a spray hole structure, hot air is ejected from the small holes, and the moisture is discharged from the exhaust pipe groove, and the hot air orifice is 15mm away from the cylinder surface. It is also equipped with a distribution air duct, a skeleton, an insulation layer, and a high temperature resistant flexible soft connection.
    The hot air system is a steam-type dual-circulation system, consisting of 2 circulating fans, 1 exhaust fan, 2 sets of steam heater units, filters, air ducts, air valves, instrument systems, etc.
    (6) Crinkle scraper group
    The scraper group of the Yankee cylinder has 1 paper-breaking scraper, 1 crumpling scraper and 1 cleaning scraper. The pressure plate of the scraper body is made of 304 stainless steel, the pressure pipe is an imported hydraulic pipe, and the blade material is SK-5, the specification is 1.25mm×130mm. Fixed slot blade fixed form, the height of the scraper is adjustable. The angle between the creping scraper and the Yankee cylinder surface can be adjusted within 10o according to the process requirements to meet the needs of various products of the paper machine.
    It is also equipped with a cylinder pressure device, a swing device and an air control device. It is also equipped with a movable knife changer and a scraper magazine.
    (7) Paper reel
    The paper reel is specially designed for high-speed toilet paper machines, including curved rollers, reeling cylinders, reeling rollers, automatic roller storage, reeling roller starting device, primary arm, secondary arm, primary paper roll brake buffer, two Grade paper roll brake buffer, roll changing device, vacuum paper guiding device, etc.
    At the same time, it is also specially equipped with paper break detection, paper roll length measurement, paper roll weight measurement, roll diameter detection and other devices to provide data to DCS so that users can achieve more scientific production management.
    (8) Lubricating oil system
    The circulating lubrication system includes a circulating lubrication center, pressure oil supply pipe and oil return pipe. The oil return from each lubrication point is collected into the oil return manifold on the operation side and transmission side of the paper machine, and flows to the lubrication center. The oil supply pressure is 4kg/cm2.
    The thin oil station is equipped with a control system, including temperature, liquid level, and flow control. The signal is connected to the DCS to interlock with the paper machine. The main components are imported products.
    (9) Hydraulic, pneumatic and paper machine control system (MCS)
    All consoles and on-site hanging boxes are stainless steel boxes, and the main components are imported products. Controlled by PLC, the signal is provided to DCS for interlocking with the paper machine drive system. In this part, the automation team has made many sophisticated designs, such as automatic control of netting tension, automatic control of reeling machine, automatic paper threading, automatic detection of bearing temperature, etc., aiming to improve the degree of automation of the paper machine, which is not only convenient for operation, but also guarantees The paper machine runs safely and stably.
    (10) Transmission control system
    The transmission form is vector control AC variable frequency divisional transmission, the control mode is three-level control, all-digital remote network PLC control; the feedback mode is digital closed-loop feedback of the photoelectric encoder; the power supply mode is the public DC bus mode. The frequency converter adopts ABB-800 series engineering vector heavy-duty frequency converter, PLC is Siemens S7-300 programmable controller, and the touch screen adopts Siemens MP277-10 touch screen, which constitutes Profibus-DP network communication control, and is connected to the paper through the upper computer. Factory DCS realizes centralized monitoring.
    Advantages of paper machine
    The 3600/1200 Crescent Toilet Paper Machine is designed and manufactured based on the modern paper machine concepts of wide format, high speed, safety, stability, energy saving, high efficiency, high quality, automation, etc. It meets the market's demand for domestic high-speed toilet paper machines and meets the needs of users. The production demand of high-quality toilet paper is a powerful guarantee for users to create value, upgrade and transform, establish brand, and expand the market.