RU2055963C1 - Slotted grading sieve - Google Patents

Abstract

FIELD: cellulose and paper industry. SUBSTANCE: slotted sieve is made of spaced longitudinal bars with fastening cross elements. The working side of cross elements is provided with slots for the bars. Each cross element is made of two parts displaced along the circumference to the middle of the slot width. The latter is equal to the sum of the doubled thickness of the bar and the gap between said gaps. EFFECT: improved design. 7 dwg

Description

 The invention relates mainly to devices used in the pulp and paper industry and constituting a component of fiber sorting. The sieve for sorting has the form of a cylindrical surface on which openings are made. Stainless steel is used as a sieve material, which requires special techniques during processing.

 Known, for example, is a method of manufacturing a sieving surface of stainless steel by A. with. N 1276372, CL B 07 B 1/46. To facilitate the processing of the material, it is subjected to hardening and heat treatment operations. This is done in order to get holes of small diameter. However, this increases the complexity of manufacturing screens.

 A device for sorting fibrous materials is known (see, for example, AS No. 1158638, class D 21 D 5/06), in which the sieve has the form of a spiral made of profiled wire fixed by gear racks. There is also known a method of manufacturing such a sieve in the form of a filter drum (see, for example, A.S. N 1152987, class D 21 D 5/02), according to which the sieve is also wound into a spiral from profiled wire, but with rings for fastening rods.

 However, these sieves do not have sufficient rigidity, are laborious to manufacture. They do not provide accuracy for filter slots.

 A sieve is known for sorting a fiber suspension according to N 1671754, cl. D 21 D 5/02, which has longitudinal profile elements that make up the sorting surface. Elements are compressed by sectors that make up the ring. Sectors have the ability to radial movement to clamp a package of profile elements.

 However, this sieve is difficult in design and laborious to manufacture. The sieve has movable sector elements. This introduces an element of insecurity.

 Known slotted sieve for sorting, including longitudinal rods installed with a gap and fastening their transverse elements, on the working side of which grooves are made to accommodate the rods (French application N 2572950, CL 01 D 39/10, 1986). A disadvantage of the known design is the complexity of the grooves for installing the longitudinal rods.

 The objective of the present invention is to remedy this drawback.

 This is achieved by the fact that each transverse element of the sieve is assembled from two parts mounted with a displacement along the circumference of one relative to the other to the middle of the groove width equal to the sum of twice the thickness of the rod and the gap between the rods.

 In FIG. 1 and 2 depict a general diagram of a cylindrical sieve; figure 3 and 4 deployed the shape and dimensions of the grooves of the rings; in Fig.5 node connecting rods and rings (deployed); figure 6 is a top view of the sorting plane; in Fig.7 section aa in Fig.5.

 Slotted sieve for sorting has profiled rectilinear rods 1 made of stainless steel. The thickness of the rods is indicated by t (figure 5). The rods may have a rectangular or wedge-shaped cross section.

 The rods are dialed into a cylindrical surface (FIG. 2) so that gaps are formed between them, through which sorting and filtering takes place. However, the rods may also make up a flat surface depending on the sorting design.

 The rods are fastened with the formation of cracks, for example, annular elements 2, as shown in figure 2. Elements can be straightforward.

 Each element 2 is composed of two parts, for example, rings 3 and 4, as shown in Fig.6 (deployed). The rings are made of stainless steel. In each ring on the working side, grooves of depth h are cut (Figs. 3 and 4). The width of the groove is equal to the sum of twice the thickness of the rod plus the gap between the two rods (2t + a). The protrusion 5 between the grooves defines the gap a between the rods.

 Rings 3 and 4 are circumferentially offset to the middle of the groove width, as shown in FIG. 3 and 4. In this case, slots are formed to accommodate the rods t (Figs. 5 and 6). These slots form an exact gap a between the rods, as well as the level of their end surface.

 Rings and rods are fastened together by welding.

 The sieve works as follows. The sieve is installed in sorting. Inside the paper pulp is injected under pressure. Through the slots, sorting of the pulp occurs.

 The design of the sieve has a simple scheme. It provides high rigidity of the sieve and high accuracy of the size of the slots. A wide groove in the rings allows you to precisely cut it in stainless steel rings with a rod thickness of 1.5-2 mm. The groove size of 5-6 mm is technologically advanced for machining stainless steel. The groove is cut with a normal normalized cutting tool, while a groove with a thickness of 2 mm without additional techniques in stainless steel is difficult to cut. In the design of the sieve, a groove of 2 mm is obtained by simply moving the rings one relative to the other due to the groove width of 6 mm.

 The sieve design is applied to a cylindrical sieve. However, such a fastening scheme of the rods is applicable, for example, for a flat sieve and for a conical one, depending on the design features of the sorting.

Claims (1)

 SLITTING SORT FOR SORTING, including longitudinal rods installed with a gap and fastening their transverse elements, on the working side of which grooves are made to accommodate the rods, characterized in that each transverse element is assembled from two parts mounted with a circumference offset from one another relative to the middle of the width a groove equal to the sum of twice the thickness of the rod and the gap between the rods.

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