FI74310B - TRAESLIPSTEN I SEGMENT SAMT SLIPSEGMENT. - Google Patents

Description

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Segmented wood grinding stone and grinding segments

The invention relates to segment-type wood grinding stones for the production of wood chips, in which the interconnected abrasive-5 segments are fixed to the center with bolts of different thermal expansion rates and which are normally subjected to a strong water jet during use to rinse the wood More specifically, the invention relates to a wood grinding stone according to the preamble of claim 1 and a grinding segment according to the preamble of claim 10.

Hitherto, many segment-type wood grinding stones have been emphasized by attaching interconnected grinding segments to both cylindrical metal and concrete centers with metal bolts and various stud-type fasteners. However, problems such as overheating, breakage, cracking and loosening of the segments have not been completely avoided and these problems arise when the metal bolts attached to the core and the segments overheat and expand faster than the grinding segments and the hub.

The overheating problem is usually due to the inability to rinse the wood chips away with copious water rinsing, whereby small wood chips particles penetrate the pores of the abrasive surface 25 and possibly clog them. Thus, the abundant rinsing water normally applied to the grinding surface is unable to penetrate between the grinding surface and the ground wood logs pressed against it and absorb and remove the excess heat generated by the grinding pressure contact. U.S. Patents 30,774,226, 2,769,286, 2,887,276 and German Patent Application No. 28,537,716 disclose a partial solution to the problem of overheating of segmented wood abrasives, the abrasive segments being bolted at intervals to a hollow cylindrical shell or shell.

Water 35 is fed into the hollow center of the wall system, or the bolts have radial ducts for directing water under pressure adjacent segments of the non-abrasive side surfaces and between them. Wood grinding stones of the types

OF

2,743,103 is disclosed in U.S. Patent 2,421,885, cooling water is not readily able to flow from the interior of the concrete hub to the grinding segments, and rinsing off the sand and preventing overheating of the grindstone rests solely on external rinsing water.

The applicant's invention relates to an improved, segmented wood grinding stone, characterized by the features mentioned in the characterizing part of claim 1. Said grooves collect the spray water and improve the penetration and efficiency of the wood-10 grindstone. This allows the operating temperature of the grinding segments and mounting bolts to be kept more even and safe. The abrasive segment according to the invention is characterized by the features mentioned in the characterizing part of claim 10.

U.S. Patents 1,132,258 and 3,132,815 disclose wood grinding stones having either continuous helical or circumferential shallow grooves or troughs which, in addition to lower and more conventional abrasive, sharpening and edge patterns, extend over the abrasive surface and form axially offset. angle. But the special function of gutters or grooves with a maximum depth of about 25 mm is to quickly collect and remove wood fibers to prevent them from re-grinding. In addition, the wood abrasive stone does not have abrasive segments attached to the center with bolts or stud bolts having different heat expansion rates, so the abrasive stones are prone to overheating of the abrasive segments attached to them.

A rotatable, segmented and grooved wood-grinding stone, consisting of prefabricated, interconnected grinding segments and bolts attached thereto, having a different rate of thermal expansion, which combination is fixed around a hub by which the wood-grinding stone can be mounted on a rotary drive. The ends 35 of the bolts with corrugations or threads are fixed by dipping or screwing the abrasive segment into the non-abrasive inner part, and the protruding ends of the bolts are intended to be fixed to the center. The circumference of the wood grindstone has a plurality of relatively deep grooves extending in the radial direction 3 7431 0 inside the outer abrasive portion of the wood abrasive stone and each abrasive segment and extending across them and forming an angle with the opposite radial surfaces of the axis of rotation and the segment.

5 During rotation, the deep grooves collect and transport colder spray water along the grooves into and through the porous abrasive and non-abrasive portions of the segments surrounding the bolts. The colder spray water flushes the wood fibers out of the grooves and, as the centrifugal force forces the water outwards, it removes the abrasive particles in the pores of the abrasive surface.

Thus, the more freely circulating spray water is able to remove the heat generated. This prevents the grinding segment road and mounting bolts from overheating and causing the grinding segments to loosen, crack and / or break.

Figure 1 shows a grooved segment wood grinding stone constructed and grooved according to the invention.

Figure 2 shows the grooved segment wood grinding stone of Figure 1 on the opposite side.

Figure 3 shows a partial magnification of a grooved grinding surface near the other end of a wood grinding stone. The figure shows the mutual fastening, the appearance of the grinding segments and the two diagonal grooves, as well as the locations of the fastening bolts.

Figures 4 and 5 show cross-sections of a portion of a wood grinding stone along line 4-4 and 5-5, respectively, of Figure 3, and the figures show grooved double grinding segments attached to a reinforced solid center with bolts screwed into the segments and embedded in the center.

Figure 6 is an overall view of a modified abrasive segment, the abrasive portion of which is provided with only one groove and is less suitable for the production of grooved wood abrasive stone.

Figure 7 shows a partial cross-section of a single groove abrasive segment of the invention secured to a hollow cylindrical hub with nuts and bolts 4 7431 0 and screwed to the abrasive segment and modified to extend through openings in the hub wall.

Figure 8 is an overall view of the combination of hub and segments with three grooves. The combination is intended as an alternative embodiment of wood grinding stone.

The drawings show an improved, circumferentially grooved, aimable, segmented wood grinding stone 10 for making wood chips. The wood grinding stone 10 consists of 10 cylindrical central bodies, i.e. a center 12 with holes 14 in the middle, constructed and arranged around the axis of rotation and between the ends so that it can be connected in a known manner to each suitable conventional drive shaft pin. Around the hub, separated by wool seals 16 of known sealing compound and fastened to the circumferential surface of the hub by conventional metal bolts 18, there are interchangeable, pivotable and mating hexagonal abrasive segments 20 in the middle and outer, i.e. at the ends, pentagonal abrasive segments 22.

Any suitable type of flexible, deformable mass can be used as the sealing compound to form the seals 16, but preferably a vulcanizable cellular rubber material containing cork particles is disclosed in U.S. Patent 2,054,771.

Depending on the purpose and type of wood grinding stone, the metal fixing bolts 18 may be of a known, conventional type and these types are disclosed in U.S. Patents 2,421,885, 2,745,226 and 2,769,286.

One end 18a of each bolt 18 is threaded or helically corrugated to a predetermined length and either end 18b has axially spaced annular protrusions and recesses therebetween, which end may be embedded in a concrete center as shown in Figure 4 or 7, 35 or the other end 18c is of a predetermined length threaded and provided with a nut and washer for attachment to a hollow cylindrical hub 12 '.

In addition, each abrasive segment 20 and 22 has at least one relatively deep groove 20b extending radially into and across the abrasive outer portion 20c of the segment portions at a predetermined angle and direction with respect to one side of the segment such that the groove extends into the groove of the adjacent segment and the intersegment. in the groove formed by the sealant 16. In summary, the grooved abrasive segments 20 and 22 and the grooved sealant gaskets 16 therebetween form a plurality of relatively long continuous grooves 20b in the wood grinding stone 10 and abrasive portions 20c therebetween, which circumferentially cover the abrasive segment 15 of the wood abrasive stone. a portion along the entire length or width of the axis of each abrasive segment, forming an angle with the axis of rotation of the wood abrasive stone and the abrasive dusts in contact with the stone. Typically, the useful and wearable abrasive portion of the finished wood abrasive stone 10 is not less than 6.5 cm. But before finishing, the radial thickness of each abrasive segment 20 and 22 is initially about 13.3 cm and the thickness of the abrasive portion is about 7.6 cm with the abrasive portion extending to the end of the threaded bolt heads 18a and the holes 20a, which determines the maximum dimensions of the non-abrasive inner circumference B and the maximum length of the holes 20a and threads 18a is about 5.7 cm.

Although the initial thickness of the abrasive portion may and does vary during use, the depth of the grooves 20b is such that their bottoms are spaced not more than 3.17 cm from the extreme circumferential boundary B which determines the end point of the bolt heads 18a.

Referring to Figures 1-5, the groove 20b may be in the shape of any groove considered suitable. But when reading the mie-35, it is V-shaped to prevent the wood chips from being trapped and to facilitate their removal or detachment.

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Each molded groove 20b is characterized by a shape in which, from above, there is an outwardly extending or curvilinearly expanding inlet with a width of about 19 mm, opposite conical walls extending from convex inlet-5 surfaces with a radius of about 12.7 mm to a concave bottom, having a width of about 4.7 mm and a radius of 2.38 mm and a groove located about 1.42 to 2.7 cm from the circumferential boundary B between the abrasive and non-abrasive parts and having an initial maximum depth of about 5.07 - 6.34 cm. Thus, regardless of wear and thinning of the abrasive portion 10, the bottom of the grooves 20b is permanently located near the peripheral boundary B and the ends 18a of the bolts 18 and allows colder rinsing water to flow through the pores of the abrasive portion and carry heat with water to prevent overheating.

Referring to Figures 3 and 4, each hexagonal inner or central grinding segment 20 of a ready-to-operate grooved wood grinding stone 10 having a diameter of about 170.8 cm and an axial length of 175.26 cm is typically located symmetrically on either side of a radial center plane extending from the axis of the wood grinding stone. Its maximum axial length at the radial median plane of symmetry is about 27.46 cm, its circumference is about 24.1 cm, and its radial thickness is about 12.7 cm at the radial median plane.

Preferably, each segment 20 is comprised of two spaced apart, slightly conical, V-shaped, diagonal grooves 20b joining together diagonal abrasive portions 20c of two parts, with two radially slightly conical sides 20d with upper edges of equal length and parallel to each other. and two pairs of slightly conical, diagonally opposite sides 20e and 20f, the equally long upper edges of which extend parallel to each other and form almost the same angle as the radial center of symmetry. Each groove 35 20b is parallel to the other grooves and extends in the diagonal direction transversely across the segment from the center with the corner or apex and is located at opposite ends of the segment from the diagonal side 20e or the diagonal side 20f and the radial plane 1 to the corner point of the opposite side, i.e. the tip located at the intersection of the radial side 20d and the diagonal side 20e.

With the exception of the absence of one side, slightly 10 different shapes and lengths, and protective end surfaces 20g, the outer or end grinding segments 22 on opposite sides of the wood grinding stone 10 are nearly similar in structure, size and shape to the corresponding portions of the central segments 20 described above. The end-15 segments are cast in the same molds as the middle segments by modifying the molds so that one end of the mold is supported by a spacer that forms the only straight end-surface 20g in the diagonal direction of the previous intersecting sides 20e and 20f. Thus, in such a mold, the molded segment 22 has two separate, diagonally parallel grooves 20b, between them an abrasive portion 20c and two radially opposite sides 20d, only one diagonal side 20e and one diagonal side 20f at one end and a straight 25 surface at its opposite end. The segments 22 are also interchangeable, pivotable, and mating with either end of the central segment 20 to align the grooves 20b of the adjacent segments 20 and 22. As can be seen from the figures, the segments 20 and 22 and the sealant 16 between them are joined in a stepped pattern, with each segment and the circumferential row of segments, including the inter-segment sealant, displacing half of the perimeter of the adjacent row. In this way, the segments and the sealing material 35 formed between them form a matching, locking and supporting system, the intermediate parts of which are formed by abrasive parts.

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As shown in Figures 1 and 3, the staggered pattern contrasts each diagonal opposite side pair 20e and 20f of the central segment 20 separated by the sealing mass material 16 with both the diagonal central segments 20 and the respective diagonal sides 20e of the end segments 22.

Referring to Figures 6 and 7, a wood grinding stone can be constructed from similar hexagonal center segments 30 and pentagonal segments 32 (not shown, but in Figure 6 the dashed line represents a straight end 30g) that are otherwise identical to segments 20 and 22 but each have only one diagonal groove 30b and abrasive parts 30c of the same size. Each groove 30b is preferably wider, but extends approximately equally sy-15 and is at the same distance from the groove 20b with respect to the circumferential boundary B 'and the end point of the bolt heads 18a. The only groove 30b extends in the diagonal direction from approximately the center of one diagonal, opposite side 30e approximately through the radial plane of the maximum length of the segment 30 and through the center of the perimeter, i.e. through the center, through the diagonal to the approximately midpoint of the opposite side 30e. Thus, the central segments 30 and the end segments 32, molded in the same mold and in the same manner as described above, are similarly interchangeable, pivotable, and sufficiently aligned with the sides of the adjacent segments to align the grooves 30b of the adjacent mating segments 30 and 32. .

Preferably, the single groove 30b has an outwardly extending or curved inlet, a width of about 3.8 cm and opposite conical sides that descend conically, i.e. approach each other as convex surfaces with a radius of n.

1.27 cm, on a concave base with a width of about 9.5 mm and a radius of 4.76 mm, located at the circumferential boundary B 'of the outer and non-abrasive inner part 35 of the segments and the wood grinding stone made therefrom.

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The segmented wood grinding stone constructed of prefabricated grinding segments 30 and 32 with a single diagonal groove and bolts 18 attached thereto has relatively 5 long, continuous, wide diagonal grooves 30b with an evenly spaced grinding portion 30c. In contrast, a wood grinding stone 10 constructed of prefabricated abrasive segments 20 and 22 with two diagonal grooves 10 and bolts 18 attached thereto has relatively long, continuous but more crimped diagonal grooves 20b of different widths at varying intervals. width abrasive portions 20c. In this way, the wood grinding stone 10 15 has evenly spaced pairs of grooves 20b and between them there are about 50% of abrasive parts 20c of the same width, so that the rest of the abrasive part 20c with the same width but different from the previous one is evenly spaced on the circumference.

In addition, the prefabricated grooved abrasive-20 segments 20, 22, 30, and 32 need not be explicitly hexagonal and pentagonal, as shown, but all suitable reversible, interchangeable polygonal segments symmetrical about the perpendicular radial and circumferential planes may be used. with one or more diagonal grooves as described above. The abrasive segments can be, for example, square, rectangular or triangular. It is also conceivable for the wood abrasive stone to be constructed by joining together grooved and / or smooth, grooved segments of varying size and asymmetrical or symmetrical in shape, in a specified order and in joining patterns different from those disclosed herein. Alternatively, a wood grinding stone constructed of conventional smooth non-grooved segments may have diagonal grooves 20b and / or 30b cut into the abrasive portion of the wood grinding stone with a diamond, boron nitride or tungsten carbide grinding wheel or cutting tool.

With the exception of the number of spaced grooves 20b and 30b on the perimeter of the grinding surface covered by the invention, the wood grinding stone 10 is approximately the same type and structure as the wood grinding stones disclosed in U.S. Patents 2,421,885 and 3,227,61111 with reinforced concrete pi centers, and 2,7,745,2 and 2,768,286 with metal-10 cylindrical or drum type hubs. For details not disclosed herein, reference is made to the said patents.

Briefly, a wood grinding stone 10 with a reinforced concrete pitch center is constructed on and with the aid of known transfer equipment or fastening means. These consist of a moving carriage or chassis, a horizontal base plate, a vertical, centering mandrel above the carriage, a top plate, a press on the circumference, presses in the radial direction and presses in the axial direction, and measuring means. A cage-shaped, circular reinforcement unit R is placed on the base plate, the diameter and axial length of which are smaller than the corresponding values of the wood grinding stone and which consists of a plurality of concentrically, radially and axially arranged reinforcing steel rings.

Connect and tighten both circumferentially and axially and concentrically around the reinforcing unit R and the central axis 30 the first circular outer row of end segments 22 or 32, then one or more inner rows of central segments 20 or 30, then the second circular outer row of end segments 22 or 32 and sealing compound seals 16. , between which the sealing compound is pressed, the cylinder 35, the reinforcing unit R and the fastening means on the movable carriage are transferred to the furnace for curing and vulcanizing the sealing compounds 16 and the abrasive segments connected thereto to form a cylindrical unit.

After curing, the assembly is transferred from the oven, allowed to cool and the two-part drum or tubular mandrel 5 is attached from the concentric reinforcement unit R

to form the center hole 14. The void space between the outer cylinder formed by the segments and the casting mandrel is filled with cement and allowed to cure sufficiently, after which the assembly is detached from the fastening means, the casting mandrel is removed and the end surfaces of the center are machined. The grooved wood grindstone is then mounted on a drive shaft pin, rotated, and the grinding surface on the periphery of the stone is finished concentrically with the axis of rotation, and the seals 16 are ground so far that the grooves 20b or 30b continue 15 uniformly in the sealant seals 16 and segments.

In contrast, a wood-grinding stone with a metal cylinder or drum center is made using a metal cylinder whose diameter, circumference, axial length, wall thickness and number of holes in the wall and the pattern formed by them are such that the bolt ends 18c can be fixed to the wall and segments in a pre-calculated number and pattern.

Thus, the prefabricated grooved abrasive segments with their mounting bolts are secured to the metal cylinder using or without the sealing compound 16 between the segments and / or the center and the segment by inserting the bolt heads 18c into the holes in the cylindrical wall. A washer and nut are threaded onto each bolt and tightened sufficiently to tension the bolts 18 to the extent that they are capable of holding the segments against the cylinder and compressing any sealant between the segments. When sealing compound seals 16 are used, the wood grinding stone assembly is placed in the furnace to secure the seal to the segments by curing and vulcanizing. In all cases, the grooved wood grindstone 35 is then mounted on a drive shaft pin, rotated, the grinding surface finished concentric with the vertical shaft, and ground 7431 0 so far out of the seal that the grooves 20b or 30b continue to be uniform in the sealing mass seals and segments.

The axial length of the bolt heads 18a is preferably about 5.7 cm and provided with a thread of 35 x 12.7 mm (1 3/8 x 0.5 ") roll-5. The length and diameter of the opposite ends 18b and 18c of these bolts may vary. But preferably the opposite end 18b has a length of about 15.2 cm and has annular protrusions at regular intervals in the axial direction with a diameter of about 2.85 cm and a width of 19 mm, and between these 10 constrictions with a diameter of about 15.8 mm and width 19 mm.

Depending on the wall thickness of the drum-like hub 12 ', the length of the opposite end 18c of the bolt varies. Typically, the opposite end is about 12.7 cm in length and -15 to 15.8 mm in diameter and has a thread of 5/8 "(15.8 mm) x 11 about 3.2 cm in length.

In both cases, each bolt 18 is made of a cold-rolled steel rail or bar with a diameter of about 2.85 cm and a length of about 18.4 or 21 cm. One end of the rail 20 or rod is inserted between the thread forming molds to form metal and form threads and grooves in the head 18a, and the other end is machined into ends 18b and 18c.

Preferably, the abrasive segments are suitably molded from the bonded abrasive by sintering and sintered in a known annealing furnace and in a known manner. The abrasive, which may be any suitable known type and grain size, is preferably alumina or silicon carbide, grain size 24 to 100. Depending on the size and shape, each segment 20 and 22 has at least one or more, preferably four, spaced threaded holes 20a. , which is adapted to receive the threaded ends 18a of the bolts. Threaded holes 20a, which may extend radially to a depth of 3.8 to 6.4 cm into the non-abrasive interior of the segment 35, are preferably molded to a depth of 7431 0 about 5.7 cm, located in the center and at almost the same distance in the diagonal direction. both from a longitudinal plane passing through the center and from a plane passing through the center perpendicular to the former. Preferably, the distance of the hole 20a from the radial plane passing through the center and from the plane perpendicular thereto is about 4.1 cm and about 5.7 cm, respectively. The attachment of the bolts 18 to the segments 20 and 22 is preferably ensured by pouring into each threaded hole 10 20a a suitable known putty, formed e.g.

a mixture of a liquid phenolic resin and finely divided abrasive or silicon particles. The kit is allowed to slowly penetrate and clog the pores in the vicinity, thereby creating a strong, impermeable and waterproof connection between the bolt head and the surrounding segment portion 15.

The excess putty is then poured out of the threaded holes 20a and the bolt heads 18a, which are further cassetteed or brushed with the putty, are screwed into the threaded grinding holes 20 and moderately tightened to a torque 20 of about 5.5 m kg to prevent stress or tensile stresses on the grinding segments. The segment is then placed in an oven to cure the resin or putty and the bolt heads 18a are permanently attached to the segments, and after curing, the segment is ready to be installed in a known manner to produce wood grinding stone 10.

Another embodiment of the invention is shown in Figure 8. It consists of reversible, interlocking and interchangeable, interconnected abrasive center segments 40 and end segments 42 which are polygonal or hexagonal and pentagonal to produce grooved, segmented wood grinding stone. Each segment 40 and 42 has threaded holes 40a for bolt heads 18a and bolts 18, a combination of three distinct diagonal grooves 40b, an abrasive surface 40c between the grooves 35, radially opposite sides 14 7431 0 40e and 40f. The diagonal grooves 40b consist of one long central groove extending diagonally between the centers of the two diagonally opposite sides 40e and fairly precisely through the midpoints of the segment 5, and two shorter counter-parallel grooves extending substantially parallel to the central groove. from the center to the diagonally opposite corners of the segment 40.

10 The appearance and depth of all the diagonal grooves 40b are almost the same as those of the other grooves 20b and 30b.

Their width may be the same as in the grooves 20b, but preferably the width is slightly smaller.

Alternatively, the combination of three grooves 40b may extend diagonally along the entire axial length of the segment such as double grooves 20b and a single groove 3Qb, which may also be shortened and extended to any axial length of the segment such as grooves 40b in Figure 8.

In addition, it is also conceivable that only one or two of the three grooves 20b extend over the entire axial length of the segment, leaving two or one shorter, leaving the wood grindstone with both long continuous and non-continuous diagonal grooves.

As shown above, the five-sided, pentagonal end segment 42, which is in fact the same as the end segment 22 but has three diagonal grooves 40b, can be cast in the same mold as the segment 40. The difference is that a spacer is placed at one end of the mold. to prevent the formation of the segment 40 or to cut off almost completely one end of the segment 40, thus creating an end segment 42 with a straight, smooth end surface 40g and three grooves 40b.

A grooved, segmented testwood abrasive stone constructed in accordance with the present invention, with double grooved, interconnected, 60 grain size silicon carbide abrasive segments and 35 reinforced concrete centers, was tested under actual abrasive conditions. The test wood grinding stone was installed in a conventional pocket-type grinder, in which longitudinally placed grinding wheels were pressed in the diameter direction against the stone, whereby the rotating grinding surface of the wood grinding stone, sized from 5 parts, grooved in the diagonal direction, grinds the logs.

There was a conventional number of conventional rinsing nozzles around the wood grinding stone, which directed a jet of cold water onto the grooved grinding surface and rinsed it with a large amount of water.

10 The results of a rather long experiment showed that no part or related segment showed overheating, splitting, slackening or cracking and did not need to be replaced or repaired. The ground fibers were qualitatively as good and in e-15 cases better than the ground fibers obtained with a smooth, grooved reference wood grindstone. The centrifugal force of the spray water more quickly removed the abrasive particles that had penetrated the pores of the abrasive surface in an attempt to clog them.

In this way, no grinding layer formed on the grinding surface, which is the cause of the segments overheating and splitting.

Rotating helical or angled grooves increased the velocity of the spray water, causing the fibers accumulated in the grooves to circulate and quickly exit the grooves. This prevented the clogging of the pores, allowed the spray water to penetrate and flow into the vicinity, and removed the heat generated on the grinding surface. It was also found that the angle-forming abrasive portions and the grooves therebetween tend to lift the elongated fibers from the owl in a manner resembling shear motion. This was due to the fact that they passed through only a small part of the longitudinal surface of the log at any moment, forming an angle, and gripping it as the movement continued. It was also found that the wood-grinding stone cut more freely, maintained a lower temperature more evenly, and the energy-35 requirement for rotation and grinding was lower.

Claims (16)

1. Liquid-cooled wood grind in segments and rotatable about its central axis, comprising a core, a plurality of tie segments with abrasive outer abrasive portions and surfaces and adjoining non-abrasive inner portions and surfaces peripherally like and attached to the core. and by means of which the abrasive stone is provided with mutually abrasive, abrasive and inner non-sealing portions and surfaces connected to each other, and having fasteners (18) which have a greater heat expansion rate than the segments (20, 22, 30, 32, 40). 42) and affixed to and preferably from the non-abrasive portions of the tie segments into the core (12) for anchoring the segments to the core (12, 12 '), characterized in that the wood abrasive has a plurality of grooves (20b, 30b, 40b), which are circumferentially distributed around and during interruption of the abrasive outer abrasive portions and surfaces (20c, 30c, 40c) preferably enter a predetermined depth in the abrasive, outer abrupt abrasives. the tiers (20c, 30c, 40c) say that the bottom of the shrimp the webs lie adjacent to the fasteners (18), at a maximum distance of 3.17 cm from a peripheral border (B, B ') between the wearable outer abrasives (20c, 30c, 40c) and the inner non-abrasive portions, which are defined by the ends of the fasteners , which are fixed at and extend from the non-abrasive portions of the tie segments (20, 22, 30, 32, 40, 42), wherein the grooves (20b, 30b, 40b) during rotation and production of fiber pulp, collect, transport and allow coolant which normally flushes and floods the grooved outer abrasive surface along the grooves 30 (20b, 30b, 40b), to rinse out the pulp, penetrate into the pores and circulate through interconnected porous areas to thereby more effectively cool the outer abrasive portion (20b, 30b, 40b) 30c, 40c) and thus prevent overheating of the fasteners (18) and resulting cracking, loosening and disintegration of the segments. 22 7431 0 Liquid-cooled grinding stone in segments according to claim 1, characterized in that the grooves (20b, 30b, 40b) extend longitudinally at an angle to the direction of rotation and the center axis of the grinding stone, and that each grinding segment (20, 22, 30, 32, 40, 42) includes at least one groove that likes diagonally in the outer abrasive abrasive portion (20c, 30c, 40c) between one end and the opposite end of the segment. Liquid-cooled grindstone in segments according to any one of the preceding claims, characterized in that each segment further comprises at least one bore (20a, 30a, 40a) of predetermined depth in the inner, non-abrasive portion, the bore being suitable. for receiving an end portion (18a) of the fastening means (18). Liquid-cooled grindstone in segments according to claim 15, characterized in that the fastening means (18) comprise at least one metal bolt (18), one end of which (18a) extends into and fixed in the bore (20a, 30a, 40a) in the non-abrasive portion of each segment and whose opposite end portion (18b) extends from the end portion 20 (18a) past the non-abrasive portion into the core (12, 12 ') and is fixed therein. Liquid-cooled grindstone in segments according to claim 3 or 4, characterized in that the bore (20a, 30a, 40a) of the inner non-abrasive portion is a threaded heel and that the bolt (18) has a threaded end portion (18a), which is screwed into and fixed in the threaded sheath (20a, 30a, 40a). Liquid-cooled grindstone in segments according to any of the preceding claims, characterized in that each of the abrasive segments (20, 22, 30, 32, 40, 42) further comprises a pair of grooves (20b, 30b, 40b). extending diagonally through the abrasive abrasive portion (20c, 30c, 40c) between one end and an opposite end of the segment. 35 Liquid-cooled grindstone in segments according to any one of the preceding claims, characterized in that a plurality of circular rows of the grooved tie segments having reversible, interchangeable polygonal shape (20, 22, 30, 32, 40, 42), arranged around the core (12, 12 '), wherein the joints (16) between adjacent segments are displaced relative to the joints between the segments in a neighboring circular segment row, thereby providing the diagonal grooves ( 20b, 30b, 40b) of segments in adjacent circular rows are aligned and preferably over at least a portion of each segment of the grindstone (10). Liquid-cooled wood grind in segments according to any of the preceding claims, characterized in that the core (12, 12 ') consists of a fixed, reinforced concrete core, which is suitable to correspond to a drive spindle, and that the opposite end portions ( 18b, 18c) of the metal bolts have one or more axially spaced apart from each other and that they are embedded in the concrete core (12, 12 '). Liquid-cooled wood grind in segments according to any one of claims 1-7, characterized in that the core (12, 12 ') consists of a preformed hollow metal cylinder, which includes a wall suitable for mounting on a drive spindle and having a heel. in the wall for receiving the opposite end portions (18b, 18c) of the metal bolts (18), and the opposite end portions (18b, 18c) of the metal bolts (18) having threaded ends which pass through the heel of the wall and attach to the the core by means of paw-screwed nuts to such an extent that the segments are poured onto the core (12, 12 '). A liquid-cooled tie segment for constructing a knurled abrasive stone in segments, wherein the abrasive stone consists of a plurality of segments mounted around and secured in a core, the abrasive segment exhibiting a mutually interchangeable, reversible, polygonal shape, predetermined axial length and circumferential width, and having an outer abrasive portion and an inner, non-abrasive portion adjoining the outer abrasive portion (20b, 30b, 40b) which is wearable, the inner portion being supported. shows at least one heel extending in the inner portion from its inner surface, and at least one bolt for securing the tie segment to the core, each bolt having greater heat expansion velocity than the segment, with one end portion of the bolt inserted into the heel. and fixed to the inner, non-abrasive portion and the opposite end portion of the bolt are adapted for attachment to the core, characterized in that the surface of the abrasive portion (20c, 30c, 40c) is interrupted by at least one diagonal a groove (20b, 30b, 40b) extending diagonally between one end of the abrasive segment to its opposite end and inset to a predetermined depth in the abrasive portion, a peripheral border (B, B1) between the inner non-abrasive portion and the the outer abrasive portion, whose circumferential border is defined by the end of the outer end portion (18a) of the bulkhead (18a), is at most 3.17 cm from the bottom of the grooves (20b, 30b, 40b). Liquid cooled tie segment according to claim 10, characterized in that the non-abrasive portion has at least one threaded heat (20a, 30a, 40a) 20 and that each bolt (18) has a threaded end portion (18a), which is screwed into the threaded heel (20a, 30a, 40a) and fixed to the non-abrasive portion of the segment. Liquid-cooled tie segment according to claim 10 or 11, characterized in that at least one diagonal groove (20b, 30b, 40b) extends substantially through and cuts the midpoint of the wearable outer abrasive portion and the surface (20c, 30c, 40c) of the segment ( 20, 22, 30, 32, 40, 42). Liquid cooled tie segment according to any of claims 10-12, characterized in that the outer abrasive portion (20c, 30c, 40c) has a pair of spaced diagonal grooves (20b, 30b, 40b) which extend substantially parallel to each other and in opposite directions between the midpoint of one and the opposite end of the segments and the diagonally located opposite corners of the segments.