FR2532399A1 - INSULATION PREFORMS FOR SAGING COOLED TUBES IN HEATING FACILITIES - Google Patents

Abstract

FOR THE INSULATING PREFORMS OF A TUBULAR SLIDE, A CARRIER TUBE OR A COOLED TRANSVERSAL TUBE OF A HEATING INSTALLATION, THE OBJECT OF THE INVENTION IS TO DEVELOP AN IMPROVED THERMAL INSULATION, PROTECTION AGAINST ATTACKS OF MILK AND SIMPLE ASSEMBLY MEANS. THE LOWER PROFILED PARTS 13, 14 ARE PREFABRICATED FROM A FIBROUS CERAMIC MATERIAL WITH A HIGH THERMAL INSULATION COEFFICIENT. THE HIGHER PROFILED PARTS 4, 5 ARE PREFABRICATED FROM A HIGH RESISTANCE CERAMIC MATERIAL. THE UPPER PROFILED PARTS 4, 5 PROTECT THE LOWER PROFILED PARTS 13, 14.

Description

* -1 -

  INSULATION PREFORMS FOR SAGING COOLED TUBES

IN HEATING FACILITIES

  The present invention relates to insulating preforms for the sheathing of tubular guides, carrying tubes or cooled transverse tubes, in the

  heating stages, these insulating preforms being

  staked by profiled parts fixed to the tubes, di-

  radially and made of different materials

  refractories. The construction of support and transport structures required in fireplaces, combustion chambers, heating zones and flue gas flues in

  different types in most cases requires

  cooling of the building elements by circulation of air, water or steam For example, the furnaces of the heating furnaces heated by above or by

  the steel industry (flexible spindle kilns)

  the pushing furnaces, etc.) are formed of round or rectangular tubes that are horizontal, are called tubular guides, carrying tubes or transverse tubes,

  and if they are vertical, straight tubes For cooling

  of these tubes, a distinction is made between cooling by cooling or cooling by vaporization according to the type of cooling, sending water, or

  superheated steam throughout the tubular system.

  To reduce the resulting high heat losses of the furnace and consequently increase its efficiency, and also to prevent as much as possible the negative effects of the cooling of the tubes on the product to be heated (slabs, ingots, eyelets, billets, etc.), It is necessary to take into account in this respect, that in addition to the thermal stresses there are also more or less strong mechanical stresses which can - 2-

  consist of attacks of calamine or lai-

  or caused by dilation, flexion and

  vibration of the tubular system Furthermore, it is ab-

  It is essential to reduce as much as possible the thickness of the insulating jacket of the tube, in particular in the case of supporting tubes and tubular guides, in order to reduce to a minimum the shadow surface of the face.

  lower heated product to be heated.

  U.S. Patents 2,693,352 and 3,781,167, the

  German Patent 2,125,885 and the Austrian patent application

  dog 552/1979 describe insulating preforms of this type.

  The profiled parts are made of compact and refractory materials in which embedded reinforcement

  These preforms, because of the high conductivity

  temperature of compact and refractory materials, have low values of thermal insulation.

  vibrations from the tubular system and is

  cutting on the steel frame frequently cause the

  rupture of inelastic profiled parts with rigid joints.

  To improve the thermal insulation coefficients

  However, attempts have been made to use insulating

  These thin mats inserted as intermediate layers between the tube and the rigid profiled piece are, however, on the one hand, a weakening of the profiled piece and cause

  on the other hand, an increase in the shadow area pro-

  throw on the product to be heated.

  the ramics alone do not provide adequate resistance

  sufficient vibration stability.

  The object of the invention is therefore to

  insulating preforms of the aforementioned type which are able to respond to the various stresses prevailing in the various peripheral zones of the tube and are

easy to assemble and disassemble.

  With insulating preforms of the aforementioned type, this result is achieved according to the invention by the fact that the

  lower profiled parts are prefabricated in one

  fibrous ceramic material and the upper profiled

  high-strength ceramic material, and that the upper profiled parts cover the lower profiled parts from above The profiled parts,

  lower side of the tube, have a low heat conductivity

  low thermal capacity, high resistance

  this to temperature variations and low weight

  lower profiled parts ensure a high level of insulation

  Moreover, their structure is not rigid, but has a certain flexibility, so they are quite insensitive to vibrations of the tube The profiled parts on the upper side are resistant against the attacks of calamine and slag and thus protect the profiled parts lower against such attacks,

  The upper profiled parts are preferably made

  made of refractory materials based on alumina silicate, silicon carbide, magnesite, etc. In a preferred embodiment of the invention, the lower profiled pieces extend over

  1800, however, on less than 2700, preferably about

  around the periphery of the tube and the parts

  spinnerets extend to the vertical tangents

  the lower profiled pieces We thus arrive at this

  that the lower profiled parts, particularly

  mically insulating materials extend over a large part of the periphery of the tube and that the upper profile

  however, completely cover the profile parts in-

  and thus protect them effectively against

  attacks of calamine or slag To improve the isolation

  thermal insulation in the area of the upper profiled

  these have veins turned towards

  the tube and between which are inserted bands of

ceramic beads or the like.

  In a preferred embodiment of the invention,

  sheet metal consoles serving as support surfaces for the parts.

  these upper profiles are welded-on the tubes The upper profiled parts do not tire the lower profiled parts and can be replaced

independently of these.

  Since they only have to bear their own weight, which is low, the lower profiled parts can therefore be applied to the tubes at

  medium of glue or refractory cement hardening cold.

  They may also be subject to the use of stirrups

retained on the tubes.

  According to another feature of the invention,

  frames are embedded in the lower profile pieces.

  In this case, it is preferable that the reinforcement comprises hooks which, for fixing the profiled parts on the tube, engage in tabs or lamellae fixed on the latter. The lower profiled parts are preferably subjected to a heat treatment before assembly so

  that they do not contract or under the influence of

  Due to temperature restrictions, the

  rental of joints and thermal bridges

  The upper profiled parts are preferably

  this made in pinion shape to prevent deterioration

  rations caused by the product to be heated or

slag.

  According to another characteristic of the invention

  two symmetrical upper profile pieces and two

  these lower profiles, which are also symmetrical, are pre-

  seen in the direction of the periphery of the tube.

  The invention will be better understood with the aid of

  description of embodiments taken as examples, but

  non-limiting, and illustrated by the attached drawing, on the-

what -5-

  FIG. 1 represents in partial section a

be with insulating preforms;

  FIG. 2 represents profiled pieces su-

  lower views from below in the direction of the arrow A according to Figure 3;

  FIG. 3 represents a sectional view of the parts

higher spun yarns; -

  FIG. 4 represents an inferior profiled piece

molded under vacuum -

  FIG. 5 represents a profiled part according to FIG. 4 with embedded reinforcements;

  FIG. 6 represents an inferior ptofilated

  formed of strips of ceramic fiber material

  FIG. 7 represents an inferior profiled piece

  similar to Figure 6, but with other arrangement of the strips and reinforcements incorporated;

  FIG. 8 represents a means of fixation pos-

  sible of a lower profiled piece on the tube;

  FIG. 9 represents a means of fixation pos-

  sible of a lower profiled part with reinforcements incor-

  porées; Figure 10 shows an enlarged view of the fastening means according to Figure 9;

  FIG. 11 represents a means of fixation pos-

  sible lower profile parts, particularly

of Figure 7.

  A tube 1 placed horizontally in a fireplace

  door riders 2 serving to support the product to heating

  iron The tube 1 is traversed by a refrigerant.

  On the outer surface of the tube 1 are fixed radial brackets 3 which are respectively placed at an angle W of approximately 30 (see FIG. 1) with respect to the horizontal axis of the tube 1 On the brackets 3 rest upper profiled pieces 4 The two profiled pieces 4 and 5 together form a pinion-shaped cover (see FIG. 3). In the region of the jumpers 2, the profiled parts 4, 5 are provided with corresponding recesses 6 and 7 (see FIG. 2) The upper profile parts 4

  and 5 have ribs 8, 9 and 10 on their underside.

  Between these ribs 8, -10 and 9, 11 is inserted

  an insulating layer 1-2 formed of ceramic fiber strips

(see figure 1) -

  The profiled parts 4 and 5 are made of

  Refractory, dense and wear-resistant materials based on alumina silicate, silicon carbide, magnesite

or the like.

  The insulating preforms furthermore comprise

  lower profiled parts 13 and 14 These are

  made of a fibrous ceramic material compared to

  parts 4 and 5, they therefore have a conduc-

  particularly low thermal and low

thermal capacity.

  The lower profiled parts 13 and 14 are

  respectively manufactured in one piece by a vacuum molding process and then subjected to a heat treatment and coated with a layer of protective paint on their

  external surface subject to stress (see

  4 and 5) The layer of protective paint may be based on silicon carbide, alumina or other fillers In each case it is hardenable cold. The lower profiled parts 13 and 14 can also be prefabricated into individual strips 15 (see FIGS. 6 and 7). In this case, the heat treatment is

  removed External surfaces subject to stress

  are coated with a layer of protective paint

type already described.

  The lower profiled parts 13 and 14 are all

  The bottom profiled piece 13 abuts the upper profiled piece 4 at the joint 17 The lower profiled piece 14 adjoins the upper profiled part 5 at the joint 18 So that the joints 17 and 18 are as narrow as possible , the profiled parts 13 and 14 have recesses 19 and 20 for receiving the brackets 3. To cover completely from above the profiled parts 13 and 14, the edges 4 'and 5' of the profiled parts

  4 and 5 extend to the vertical tangents

  shims T of profiled parts 13 and 14 -

  The seal 16 and the upper seal 21 between the two profiled pieces 4 and 5 as well as the joints formed between the recesses 6 and 7 and the jumpers 2 and the joints of the profiled pieces, seen in the longitudinal direction of the tubes

  are sealed with a refractory cement.

  The length of the various profiled pieces 4, 5 t 13, 14 is preferably calculated so that each time three profiled pieces are used per running meter.

of tube.

  To increase the stability of profiled parts

  13 and 14, metal reinforcements 22 are

  in those shown in the examples of reali-

  according to FIGS. 1, 5, 7.

  The profiled parts 13 and 14 can be glued directly to the tube by means of a cold hardenable adhesive. However, they can also be subjected to

  tube 1 by means of mechanical fasteners Such fixa-

  are shown in FIGS. 8-11.

  In the exemplary embodiments according to FIGS. 8 to 10, slats 23 - in which can engage

  plate angles 24 are welded to the tube 1.

  In the embodiment of FIG. 8, the

  angle 24 has points 25, 26 disposed in the-

  longitudinal direction of the tube These tips 25 and 26 sink into the material of the profiled parts 13 and 14 In this way, each bracket 24 respectively maintains two profiled parts 13 and 14 at their turned edges

  towards each other; The possibility of moving the cor-

  24 in the slats 23 makes it possible to compensate

lances of length.

  In the embodiment of FIGS. 9 and 10, on the angle 24 is fixed a tubular sleeve 27 making

  protruding on both sides in the direction of the length of the tube.

  The sleeve 27 is designed so that in each of its ends can engage the metal frames 22

  in the form of bars of the adjacent profiled parts 13 and 14.

  This mode of attachment is especially recommended when

  formed insulators are exposed to particular vibrations.

strong.

  In the embodiment according to Figure 11-, hooks 28 are disposed on the outer surface of the tube 1 On these hooks can be fixed profiled parts 13 and 14 which, on their inner face, comprise a coating

  metal made of expanded metal 29, a metal sheet

  drilled or the like rigid to bending.

  In case of wear, the upper profiled parts 4 and 5 and the lower profiled parts 13 and 14 can be replaced independently of each other. The upper profiled parts 4 and 5 do not rest on the

  lower profile parts 13 and 14, but on the

  the 3 can therefore easily be removed from

  consoles 3 and replace them without dismantling the parts

  these lower sections 13 and 14 In the same way, the

  lower profile parts 13 and 14 can be replaced

separately.

  The upper profile pieces 4 and 5 are extremely

  resistant to slag attack.

  clamp the lower profiled parts 13 and 14 against such attacks The lower profiled parts 13 and 14

  mainly ensure the thermal insulation of the tube 1.

9-

Claims (7)

  1. Insulating preforms for sheathing a slip   tube, a carrier tube or a transverse tube   cooled, of a heating installation, these pre-   insulators being constituted by profiled pieces fi xed on the tube, radially divided and made of a refractory material, characterized by the fact that the lower profiled parts (13, 14) are prefabricated   in a fibrous ceramic material while the parts pro-   spun yarns (4, 5) are prefabricated of a high-strength ceramic material and cover from above the lower profiled parts (13-, 14): = 2. Insulating preforms according to claim 1,   characterized by the fact that the lower profiled parts   eures (13, 14) extend over more than 180, however   less than 270, preferably about 240, around   the periphery of the tube (1) and that the profiled parts su-   lower (4, 5) extend to vertical tangents   (T) lower profiled pieces (13, 14).   Insulating preforms according to claim 1 or   2, characterized by the fact that the upper profile pieces   (4, 5) are without metal reinforcement, 4 o Insulating preforms according to any one of   preceding claims characterized by the fact that   the upper profiled parts (4, 5) have   vures (8 to 11) facing towards the tube (1) and between which   are inserted strips of ceramic fibers (12).     Insulating preforms according to any one of   preceding claims characterized by the fact that   the upper profiled pieces (4, 5) are made of pinion shape.   6 insulating preforms according to any one of   preceding claims characterized by the fact that   two symmetrical upper profile pieces (4, 5) are   provided in the direction of the periphery of the tube.   - 7. Insulating preforms according to any one of   preceding claims, characterized in that the   tube (1) comprises brackets (3) serving as contact surfaces   to the upper profiled parts (4, 5).   8 Insulating preforms according to any one of   preceding claims characterized by the fact that   the lower profiled parts (13, 14) made of   Many are vacuum molded parts.   9. Insulating preforms according to claim 8, characterized in that the profiled parts (13, 14)   are subjected to a heat treatment.   10. Insulating preforms according to any one of   claims 1 to 7, characterized by the fact that   lower profiled parts (13, 14) are constituted by   strips (15) of fibrous material.   11. Insulating preforms according to any one of   preceding claims characterized by the fact that   two symmetrical lower profile pieces (13, 14) are   provided in the direction of the periphery of the tube.   12 Insulating preforms according to any one of   preceding claims characterized by the fact that   the lower profiled parts (13, 14) comprise a metal frame (22, 29).   13. Insulating preforms according to claim 12,   characterized in that the tube (1) comprises   fixing yen (23, 24, 27, 28) which cling to the mature metal (22, 29).   14. Insulating preforms according to any one of   claims 1 to 12, characterized by the fact that   lower profiled parts (13, 14) are glued on the tube (1).   15. Insulating preforms according to any one of   claims 1 to 12, characterized by the fact that   lower profiled parts (13, 14) are attached to the   tube (1) by means of spikes (25, 26) disposed thereon deny.