FIELD OF THE INVENTION
The present invention relates to construction of ash hopper of furnace. In particular, the present invention relates to a supporting structure for the ash hopper and more particularly, the present invention relates to a structure for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper.

BACKGROUND OF THE INVENTION
Generally boilers are employed in power plants to generate energy by burning coal in the furnaces of the boilers. The by-product of the combustion of coal, mainly bottom ash, comprises accumulations of ash which are heavy enough to fall down to the bottom of the furnace of the boiler. The bottom ash which is falling down is guided and collected in an ash hopper positioned beneath the boiler. The ash hopper is joined to the vertical walls of the boiler. However, the vertical walls are usually not equipped to withstand the weight of the ash hopper, the weight of the insulating materials covering the ash hopper and the weight of the clinkers collected in the ash hopper. Hence, the ash hopper is usually supported by obliquely positioned support structures positioned at the sides of the ash hopper. The support structures deliver the weight of the ash hopper and other associated elements described above to vertical walls of the boiler via a wall channel in a uniform manner.

In order to transfer the weight of the ash hopper and other associated elements to the vertical walls, specially constructed joining arrangements were used conventionally. It has been observed that fabrication of the conventional joining arrangements is very difficult. It has also been observed that any marginal variation from the original design such as variation in distance between the wall channel and the oblique buckstay would make the specially constructed joining arrangements non-usable. Alternatively, the specially constructed joining arrangements may require to be modified at the installation site for accommodating any variation from the original design. In some instances, modifications to the specially constructed joining arrangements cannot be performed due to other design considerations. Therefore, this results in loss of material, time and manpower.

Thus, there exists a need to provide an improved structure for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper to overcome the above-mentioned problems.

OBJECTS OF THE INVENTION
The primary object of the present invention is to provide a supporting structure for an ash hopper of a furnace.

Another object of the present invention is to provide a structure for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper.

SUMMARY OF THE INVENTION
Accordingly, the present invention relates to a structure for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper, said structure comprising a wall plate attached to the sling; an upwardly projecting channel element connected at a right angle to the oblique buckstay; and a linking element connecting the wall plate to the upwardly projecting channel element, characterized in that the linking element is of an adjustable length; the wall plate is provided with a pivot hole for connecting to one end of the linking element; and an inner flange of the upwardly projecting channel element is provided with a protrusion plate having a pivot hole for connecting to the other end of the linking element.

BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention are set forth with particularity in the appended claims. The invention itself, together with further features and attended advantages, will become apparent from consideration of the following detailed description, taken in conjunction with the accompanying drawings. One or more aspects of the present invention are now described, by way of example only, with reference to the accompanied drawings wherein like reference numerals represent like elements and in which:

Figure 1 illustrates a view of a structure for joining for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper according to an aspect of the present invention.

Figure 2 illustrates an embodiment of linking element according to an aspect of the present invention.

Figure 3 illustrates an embodiment of linking element according to another aspect of the present invention.

Figure 4 illustrates an embodiment of linking element according to another aspect of the present invention.

Skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
While the invention is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the invention as defined by the appended claims.

Before describing in detail embodiments it may be observed that the novelty and inventive step that are in accordance with the present invention reside in the construction of the structure for joining the ash hopper corner to a buckstay arrangement, accordingly, the drawings are showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, device that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such setup or device. In other words, one or more elements in a system or apparatus proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.

The present invention relates to construction of ash hopper of furnace. In particular, the present invention relates to a supporting structure for the ash hopper and more particularly, the present invention relates to a structure for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper.

Accordingly, the present invention relates to a structure for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper, said structure comprising a wall plate attached to the sling; an upwardly projecting channel element connected at a right angle to the oblique buckstay; and a linking element connecting the wall plate to the upwardly projecting channel element, characterized in that the linking element is of an adjustable length; the wall plate is provided with a pivot hole for connecting to one end of the linking element; and an inner flange of the upwardly projecting channel element is provided with a protrusion plate having a pivot hole for connecting to the other end of the linking element.

In an aspect of the present invention, the linking element comprises a turnbuckle having external threaded end sections; and a pair of stubs disposed on the ends of the turnbuckle wherein the stubs engage with the external threaded section of the turnbuckle and the length of the linking element is adjusted by rotation of the stubs.

In another aspect of the present invention, the linking element comprises a turnbuckle having internal threaded end sections; and a pair of stubs disposed on the ends of the turnbuckle wherein the stubs engage with the internal threaded section of the turnbuckle and the length of the linking element is adjusted by rotation of the stubs.

In yet another aspect of the present invention, the linking element comprises a pair of T-shaped members, having cross arms, with one member being provided with a central recess for accommodating a projecting structure of the other member extending into the said recess; and a pair of headed bolts threadedly engaged by nuts, said bolts bored on the cross arms of each of the T-shaped members.

In still another aspect of the present invention, the pair of stubs is provided with holes for pivotally connecting to the holes on the wall plate and the protrusion plate.

In another aspect of the present invention, the pair of stubs is connected to the wall plate and the protrusion plate by means of a respective link pin.

In yet another aspect of the present invention, the pair of T-shaped members is provided with holes for pivotally connecting to the holes on the wall plate and the protrusion plate.

In still another aspect of the present invention, the pair of T-shaped members is connected to the wall plate and the protrusion plate by means of a respective link pin.

In another aspect of the present invention, the linking element is couple-able to each of the front and rear side of the wall plate and the protrusion plate respectively.

Referring to figure 1, a furnace is illustrated to be formed of water wall tubes (1). The water wall tubes can be either of vertical type or of spiral type. On an exterior portion of the wall tubes, a sling member (4) is provided. The sling member (4) provides an even surface for connection of support structures (such as vertical and horizontal buckstays which are not shown) which are needed to support the water wall tubes (1).

At a bottom end of the furnace, an ash hopper (2) is provided for collecting bottom ash. The ash hopper (2) is supported from exterior by obliquely located buckstays (3). Although in figure 1, for the sake of simplicity, the ash hopper (2) is shown as being supported only on a left side by buckstay (3), the ash hopper (2) is supported by plurality of obliquely located buckstays (3) on all four sides. The oblique buckstays (3) can be formed of “I” beams or “T” beams or truss structure.

The obliquely located buckstays (3) are connected to the water wall tubes (1) (and more particularly to the sling members (4)) for transferring at least part of load experienced by the same on to the water wall tubes (1). Once the load thus experienced by the obliquely located buckstays (3) has been transferred to the water wall tubes (1), the same can be thereafter transferred to support structures which support the water wall tubes (1).

Thus, according to the present invention, the structure for joining sling member of a water wall tube to an oblique buckstay that supports an ash hopper comprises a wall plate (5) attached to the sling member (4), an upwardly projecting channel element (6) connected at about a right angle to the oblique buckstay (3) and at least one linking element (7) connecting the wall plate (5) to the upwardly projecting channel element (6).

The wall plate (5) is welded to the sling member and comprises a pivot hole (8a) for enabling connection of one end of the linking element (7) thereto. For enabling other end of the linking element (7) to be connected to the upwardly projecting channel element (6), an inner flange portion (9) of the same is provided with a protrusion plate (10). The protrusion plate (10) is provided with a pivot hole (8b) for enabling connection of the other end of the linking element (7) thereto.

The manner of connecting the ends of the linking element (7) to the upwardly projecting channel element (6) and the sling member (4) described above minimizes tension and pressure fed on the walls of the ash hopper (2) as well as the water wall tubes (1).

Furthermore, the linking element (7) is constructed such that the same is of adjustable length. More particularly, the length of the linking element (7) is adjustable prior to being linked to the wall plate (5) and the protrusion plate (10). The length of the linking element (7) however is not adjustable after the same has been linked to the wall plate and the protrusion plate.

If needed, the wall plate (5) and the protrusion plate (10) can each be replaced by a wall block and a protrusion block having a predetermined amount of thickness and the number of linking elements thus connecting them can be increased.

The linking element (7) can be selected from any of the linking elements illustrated in any of figures 2 to 4. The linking element (7) illustrated in figure 1 is illustrated in shown in details in figure 2 and the same comprises a solid turnbuckle (11) and a pair of hollow stubs (12a and 12b). The hollow stubs (12a and 12b) are located at end sections of the solid turnbuckle (11). Each of the stubs is provided with internal threading and the end sections of the turnbuckle (11) are provided with external threading for engaging with each other. The length of the linking element (7) is adjusted by rotating one or both of the stubs (12a and 12b) with respect to the turnbuckle (11) or by rotating the turnbuckle. The stubs (12a and 12b) are substantially hollow cylindrical structures having a slot at one end for accommodating the wall plate (5) and/or the protrusion plate (10), i.e. the stubs have coaxially disposed pivot holes near the said one end which can be aligned with the holes of the wall plate (5) and/or the protrusion plate (10) and can be connected using link pins (13a and 13b).

In an alternative embodiment illustrated in figure 3, the linking element comprises a hollow turnbuckle (14) and a pair of solid stubs (15a and 15b). The stubs (15a and 15b) are located at end sections of the turnbuckle (13). Each of the stubs is provided with external threading and the end sections of the hollow turnbuckle are provided with internal threading for engaging with each other. The length of the linking element is adjusted by rotating one or both of the stubs with respect to the turnbuckle or by rotating the turnbuckle. The stub (15a) illustrated in figure 3 comprises of a cylindrical front portion having external threading and a rear flattened portion having a slot (16a). The flattened rear portion of the stub is located on either the front and/or the rear side of the wall plate (5), the slot (16a) in the stub (15a) aligned with the slot provided in the wall plate (5) and connected using a link pin. Similarly, the stub 15b illustrated in figure 3 comprise a cylindrical front portion having external threading and a rear flattened portion having a slot (16b). The flattened rear portion of the stub (15b) is located on either the front and/or the rear side of the protrusion plate (10), the slot (16b) in the stub (15b) aligned with the slot provided in the protrusion plate (10) and connected using link pin.

In yet another alternative embodiment illustrated in figure 4, the linking element comprises a pair of T-shaped members (17a and 17b) having cross arms. The cross arms of each of the T-shaped member are bored to receive a pair of headed bolts (18a and 18b) which are threaded by two pair of nuts (19a and 20a, 19b and 20b). The nuts are disposed such that one arm of T-shaped member (17b) is placed between nuts (19a and 20a). Similarly, the other arm of T-shaped member (17b) is placed between nuts (19b and 20b). The pair of nuts is arranged such that the effective length of the linking element can be altered by rotation of the bolts (18a and 18b) to adjust the effective distance between the T-shaped members (17a and 17b). Each of the T-shaped members (17a and 17b) is provided with a hole (21a and 21b) respectively for pivotally connecting to the holes in the wall plate (5) and the protrusion plate (8).

ADVANTAGES OF THE PRESENT INVENTION
The present invention has the following advantages:

1. The present invention provides an improved supporting structure for ash hopper of a furnace.
2. The supporting structure of the present invention minimizes tension and pressure fed on the walls of the ash hopper.
3. The supporting structure of the present invention is simple and cost effective.
4. The supporting structure of the present invention is flexible in terms of installation.

While the particular preferred embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the teachings of the invention. It is therefore contemplates that the present invention cover any and all modifications, variations or equivalents that fall within the scope of the basic underlying principles disclosed above and claimed herein.

We Claim:

1. A structure for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper, said structure comprising:
a wall plate attached to the sling;
an upwardly projecting channel element connected at a right angle to the oblique buckstay; and
a linking element connecting the wall plate to the upwardly projecting channel element, characterized in that:
the linking element is of an adjustable length;
the wall plate is provided with a pivot hole for connecting to one end of the linking element; and
an inner flange of the upwardly projecting channel element is provided with a protrusion plate having a pivot hole for connecting to the other end of the linking element.

2. The structure as claimed in claim 1, wherein the linking element comprises:
a turnbuckle having external threaded end sections; and
a pair of stubs disposed on the ends of the turnbuckle wherein the stubs engage with the external threaded section of the turnbuckle and the length of the linking element is adjusted by rotation of the stubs.

3. The structure as claimed in claim 1, wherein the linking element comprises:
a turnbuckle having internal threaded end sections; and
a pair of stubs disposed on the ends of the turnbuckle wherein the stubs engage with the internal threaded section of the turnbuckle and the length of the linking element is adjusted by rotation of the stubs.

4. The structure as claimed in claim 1, wherein the linking element comprises:
a pair of T-shaped members, having cross arms, with one member being provided with a central recess for accommodating a projecting structure of the other member extending into the said recess; and
a pair of headed bolts threadedly engaged by nuts, said bolts bored on the cross arms of each of the T-shaped members.

5. The structure as claimed in claims 2 or 3, wherein the pair of stubs is provided with holes for pivotally connecting to the holes on the wall plate and the protrusion plate.

6. The structure as claimed in claim 5, wherein the pair of stubs is connected to the wall plate and the protrusion plate by means of a respective link pin.

7. The structure as claimed in claim 4, wherein the pair of T-shaped members is provided with holes for pivotally connecting to the holes on the wall plate and the protrusion plate.

8. The structure as claimed in claim 7, wherein the pair of T-shaped members is connected to the wall plate and the protrusion plate by means of a respective link pin.

9. The structure as claimed in claim 1, wherein the linking element is couple-able to each of the front and rear side of the wall plate and the protrusion plate respectively.

10. A structure for joining sling of water wall tube to an oblique buckstay supporting furnace ash hopper substantially such as herein described with reference to the foregoing description and the accompanying drawings.