GB2276232A

GB2276232A - A return flow line port for a fuel-fired boiler

Info

Publication number: GB2276232A
Application number: GB9405010A
Authority: GB
Inventors: Walter Weil
Original assignee: RAPIDO WAERMETECHNIK GmbH
Current assignee: RAPIDO WAERMETECHNIK GmbH
Priority date: 1993-03-17
Filing date: 1994-03-15
Publication date: 1994-09-21
Also published as: NL9400373A; GB9405010D0; DE4409676A1; DE9404811U1; FR2702827A1

Description

2276232 A return flow line port for a fuel-fired boiler The present

invention relates to a return f low line port for a fuel-fired boiler, which comprises a heat exchanger comprising separate sections, which have cavities through which water flows and are provided with a flow line port, wherein the return flow line port comprises a tube which extends through a plurality of boiler sections and is provided in its shell with exit openings.

Such return flow line ports for sectional cast iron boilers have been previously proposed. The tube serves to distribute the inflowing water uniformly, which is often rather cold, to all the water compartments of the separate boiler sections in order to avoid supplying is individual boiler sections with return flow water that is particularly cold and thus ensuring that there will be only small temperature differences between the foremost and rearmost sections.

Boilers for central heating systems are sometimes initially supplied without such return flow line ports and may subsequently be provided with the tubes. In such cases it will be difficult to install that tube if the boiler stands in a corner of the cellar and owing to the constricted space available around the installed boiler, the relatively long tube cannot be inserted into the return flow line port opening. This may also occur when a new boiler is to be installed and owing to the size of each boiler section the boiler sections are connected by nipples on the site and the tube of the return flow line port must be inserted after the connections by the nipples have been made, i.e., after the several boiler sections have been connected to form the heat exchanger block. In such cases the block of boiler sections is so heavy that it can hardly be moved, and the tube is so long that it can no longer be inserted.

An aim of the present invention is to obviate the disadvantages outlined hereinbefore and to provide a return flow line port comprising a tube which can readily be inserted even in a constricted space during the installation of a new boiler or when the boiler is to be retrofitted.

is According to the present invention there is provided a return line port for a fuel-fired boiler as described in the opening paragraph of the present specification in which the tube comprises a plurality of tube sections, which are adapted to be interfitted with one or more sleeve joints.

Owing to said joint or joints the tube or the tube sections can easily be removed from the boiler, as is often required during service work.

The present invention extends to a fuel-fired boiler, which comprises a heat exchanger comprising separate sections, which have cavities through which water f lows and are provided with a f low line port and with a return flow line port, which comprises a tube and extends through a plurality of boiler sections and is provided in its shell with exit openings, in which the tube comprises a plurality of tube sections, which are adapted to be interfitted with one or more sleeve joints.

An example of a return flow line port made in accordance with the present invention is shown in the accompanying drawings, in which:

Figure 1 is a transverse sectional view of part of a boiler of a central heating system; and Figure 2 is a sectional view showing part of Figure 1 in greater detail.

A cast iron boiler for a central heating system is shown in Figure 1 and comprises a combustion chamber 1, is which contains a burner (not shown in the drawing). The combustion chamber 1 is surrounded by a heat exchanger 3, which comprises a plurality of separate cast iron boiler sections 4, which comprise a foremost boiler section, a rearmost boiler section, and intermediate boiler sections.

At least the intermediate boiler sections have cavities 5, through which water flows. All the cavities 5 are connected to a f low line port (not shown) and a return f low line port 6. The flow line port and the return flow line port 6 are hydraulically interconnected by a flow line, a return flow line, a plurality of radiators connected in parallel and/or in series and a circulating pump. The return flow line port 6 comprises a tube 8, which has been inserted to extend through cavity portions 7 of the boiler sections 4. The tube 8 is cylindrical and at its cylindrical shell has separate water exit openings9, through which the inf lowing cold water from the return flow line is uniformly distributed through the cavity portions 7 to the separate cavities 5 of the boiler sections 4 so that all of them are uniformly supplied with cold water from the return flow line. The tube 8 which extends through the boiler sections must be closed at one end 10 and is provided at its other end 11 with a sealing flange 12, which is joined to the foremost or rearmost boiler section. Figure 1 illustrates two joints 13 and 14 so that the tube of the return flow line port comprises three tube sections, the two rear ones of which are designated 15 and is 16. One of the joints is shown on a larger scale in Figure 2. It is apparent there that the separate tube sections 15, 16 are joined at the joint 13, which is covered on the inside by a sleeve 17. The sleeve 17 might alternatively cover the outside peripheral surface of the tube sections 15 and 16. The sleeve 17 is permanently joined to one tube section 15 by one or more spot welds 18 and has merely been fitted into the other tube section 16. If the boiler and the tube 8 have a large length so that there are a plurality of joints 13, 14..., said joints 13, 14 will be identical.

The first tube section provided with the flange ill may be extended in length one or more times. During the installation, the sections of the heat exchanger 3 are connected by nipples and that tube section 16 which comprises the end 10 is inserted first. Thereaf ter the next tube section 15 is inserted and is f itted on the sleeve 17 in the interior of the cavity portions 7. The resulting subassembly is further inserted into the boiler and the next joint 13 is made, until the tube 8 for the return f low line port 6 has been assembled to its full length.

6

Claims

A return flow line port for a fuel-fired boiler, which comprises a heat exchanger comprising separate sections, which have cavities through which water f lows and are provided with a flow line port, wherein the return flow line port comprises a tube which extends through a plurality of boiler sections and is provided in its shell with exit openings, in which the tube comprises a plurality of tube sections, which are adapted to be interfitted with one or more sleeve joints.
2. A return flow line port for a fuel-fired boiler, which comprises a heat exchanger comprising separate sections, which have cavities through which water flows and is are provided with a flow line port, substantially as described hereinbef ore with ref erence to and as shown in the accompanying drawing.
3. A fuel-fired boiler, which comprises a heat exchanger comprising separate sections, which have cavities through which water flows and are provided with a f low line port and with a return f low line port, which comprises a tube and extends through a plurality of boiler sections and is provided in its shell with exit openings, in which the tube comprises a plurality of tube sections, which are adapted to be interfitted with one or more sleeve joints.