FI65855C - CONVENTIONS WITH CENTRAL CENTER ELLER LIKNANDE - Google Patents

Description

2 65855

By means of the invention, the efficiency of the convection part can be substantially increased. In the embodiment shown, convection pieces formed of plate-like metal pieces rotated about their longitudinal axis are fixed to the wall of the convection part.

The invention and its other advantages will be explained in detail below with the aid of the accompanying drawings.

Figure 1 shows a section of a preferred embodiment of the invention

Figure 2 shows a section B-B of Figure 1.

In the embodiment of the invention according to Figures 1 and 2, the flue gases enter the convection part from the opening 1. Several horizontally extending convection surfaces are attached to the walls of the convection part. The convection surfaces consist of separate convection pieces 2, 3 formed by plate strips wound around its longitudinal axis.

The convection pieces are placed on the walls in two different positions. The pieces marked with reference numerals 2 are horizontal in their attachment points. Thus, they form a significant flow resistance next to the wall. However, due to the longitudinal rotation of the bodies, a flow channel is formed in the middle of the convection surface, in which the resistance caused by the convection bodies is small. The convection pieces 3 are again fixed to the walls so that they are vertical next to the wall. In this case, the gases can flow upwards next to the wall, but in the middle of the convection surface the flow resistance is correspondingly high due to the horizontal parts of the convection bodies. This creates a flow in the convection section according to the arrows A.

Each convection surface is provided with a heat transfer surface 3 at the water side end. Without heat transfer surfaces, the boiler wall easily overheats and causes boiling.

65855 3

The convection surfaces are grouped into groups 4 of two surfaces, the distance of which is greater than the distance between the convection surfaces of the group, as can be seen from Figures 1 and 2. These groups 4 are separated from each other by dampers 1, 7, 8, 9.

The flow of gases in the convection section is controlled by control dampers 7, 8, 9. With different positions of the dampers, a suitable amount of convection power can be selected for use. With the dampers in the position of Figure 2, the flue gases flow according to arrows B and further from the opening 22 to the flue or the like.

The invention has been described above with reference only to one of its preferred embodiments, but it is clear that the invention can be modified in many ways within the scope of the appended claims. For example, the convection pieces can be twisted several times in the direction of their longitudinal axis. In addition, the number and location of the convection surfaces can be varied as desired.

Claims (3)

4 65855 A convection part of a central heating boiler or the like, the walls of the boiler of which are preferably provided with horizontal or almost horizontal convection surfaces consisting of separate convection bodies, characterized in that - the convection bodies (2, 3) are formed of plate-shaped metal bodies the convection pieces (2) of the convection surface are fixed to the boiler wall so that they are parallel to the convection surface in their attachment points and the convection pieces (3) of each other convection surface so that they are vertically against the convection surface at their attachment point. Convection section according to Claim 1, characterized in that the convection surfaces are grouped into groups (4) of two surfaces, the distance of which is greater than the distance between the convection surfaces of the group. Convection section according to Claim 1 or 2, characterized in that the convection bodies (2, 3) of the convection surfaces are provided with a heat transfer surface 1a (5) at their water-side end.