SU867987A1 - Wet suction box of wire end of paper-making machine - Google Patents

Description

The invention relates to the co-structuring of a paper machine, and may find application in the pulp and paper industry. Devices are known that improve the uniform distribution of fibers in the sheet structure by exposing steam jets to a sheet of paper at some distance from the outlet slot of the headbox, as well as using the hydraulic jump phenomenon, which leads to horizontal flows and frustration of the pulp y. Also known are devices in which to more evenly distribute the fibers, to better interweave them, to increase the paper strength in the direction of circulation, the papermaking machine grid in the area between the chest shaft and the suction pads is machined in a horizontal plane, perpendicular to its direction of travel G21. Although the use of three wheels contributes to improved paper quality indicators, however, its efficiency decreases sharply with an increase in the paper machine speed of 250–350 m / min. The use of mechanisms three ways considerably complicates the design of grid tables, leading to a decrease in the reliability of their work. Closest to the proposed offer is a wet suction box of the grid part of the paper machine, comprising a housing with a pump cover and a valve with a float for adjusting the water level. The uniform distribution of the fibers is achieved by partially eroding the paper structure when running onto the strips forming the lid of the wet suction drawer. The known devices have the following disadvantages. Application

the scraper bar for papermaker mesh speeds below 300 m / min is ineffective, while increasing the machine speed over 300 m / min, it’s very difficult to choose the optimal operation mode, their shape, quantity and installation site for , the required effect of mass expansion and alignment of its structure.

The purpose of the invention is to improve the quality of the cast sheet by providing a more uniform distribution of the fibers in the sheet structure.

The goal is achieved by the fact that a wet suction unit has a device for the turbulization of a layer molded on a grid of a web consisting of a plate installed in the case of the box parallel to its key and connected to it

The drawing shows a wet suction box, a cross-section.

The wet suction box contains a housing 1, having in the upper part of the rib 2 to support the cover 3, water pump 4 with an adjusting valve 5 and a valve 6 for leveling the float 7. The plate 8 is placed in the housing 1 and is rigidly connected to the spring-loaded. ) 1 rods 9 which are connected with a vibration drive 9M made in the form of eccentrics placed on the drive shafts 10 cam mechanisms. The vibration drive can be made in the form of cores of electromagnetic coils connected to an alternating voltage generator. The springs 11 are designed to close the eccentric mechanisms. The device works as follows. Simultaneously with the feeding of the paper pulp to the papermaking machine grid, the bending vibrations of the plate 8 are excited with vibrators 10 interacting with spring-loaded rods 9. The wet suction box works under the bay. The coarse adjustment of the amount of water withdrawn is carried out by the adjusting valve 5. When the water level in the snap is lowered, the float 7 is lowered, the valve 6 opens and a part of the water goes back IB chic to reduce the level. This sets the balance of the water.

incoming and discharged from the box by the pump 4 ,,

Claims (3)

Under the influence of acoustical acoustics, the paper mass on the grid is thoroughly turbulized, which helps to level the uneven distribution of fibers caused by poor quality work of the flue systems of paper machines. Y., the intensity of the generated turbulence depends on the amplitude, JJa scale depends on the frequency of the flexural oscillations of the mold 8. The selection of the optimal frequencies and amplitudes of the flexural oscillations of the plate was carried out separately for each type of paper produced. The adjustment of the part and the amplitude of the vibrator in the proposed device is carried out by selecting the speeds of rotation of the drive shaft and the value of the eccentricity. theta eccentrics or magnitude hour-. The currents and voltages of the current are magnetized in electromagnetic coils, and at low operating frequencies cam-type vibrators are used, and at elevated frequencies, vibrators in the form of electro-magnetic catholes are used. The use of the invention allows, at the expense of increasing the uniformity of distribution in the sheet structure, to produce products at a lower mass limit 1. . , 1 Reducing the mass of 1 produced product is one of the most important ways to increase production efficiency, as it allows to save scarce fibrous semi-finished products and materials, reduce the cost of transporting and storing products, etc. Claims The wet suction machine of the grid part of a paper machine, comprising a housing with a cap, a pump and a valve with a float for adjusting the level of water, is characterized in that, in order to improve the quality of the molded web, it has a device dp turbulization of the layer formed on the web-mesh consisting of a plate mounted in the case of the box parallel to its base and connected to it by a vibro drive. Sources of information: taken into account during the examination 1. Kugushev I. D. The theory of processes of reflux and dehydration of paper pulp. M., Lesna industry, 1967, p. 95 2. Aidley} I.Ya. Papermaking and finishing machines. 1970, p. 190. 3. USSR author's certificate No. 362106, cl. О 21 F 1/48, 1967 (prototype).