JPH09292087A - Multistage orifice - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multistage orifice which is used for water supply piping, reduces assembling and installing time, and facilitates change of specification of an orifice during operation. SOLUTION: A multistage orifice 1 has a case 3, orifices 2 and a coupling 4. The case 3 is cylindrically formed, having one end provided with a connection part 3d to which a water supply pipe 10 is connected, a reception seat 3c on its inner and lower sides formed with a water through-hole 3a, and a screw part 3b on its inner and upper side. The orifice 2 has a cup-like form, and a water through-hole 2a formed on a flat portion 2b. The coupling 4 has a connection part 4d to which the water supply pipe 10 is connected on its upper side, a water through-hole 4a for communicating the connection part 4d with the lower surface side on its inner side, and a screw 4b screwed with the screw 3b of the case 3 on its lower and outer peripheral part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a multi-stage orifice used for various water supply pipelines such as boiler water supply pipelines.

[0002]

2. Description of the Related Art FIG. 3 shows an example in which a multi-stage orifice is applied to a boiler water supply line, in which water W is supplied to a water supply circuit 6 via a deaerator 5, in which case steam is supplied. It is heated by S, then pressurized to a predetermined pressure by the high pressure pump 13, and then supplied to a boiler (not shown).

In this boiler water supply line, the motor 12
In order to prevent overheating at the time of starting the high-pressure pump 13 driven by, the circulation circuit 7 that connects the pump outlet and the deaerator 5 is generally provided, and the circuit 7 is provided with an on / off valve 14 and the multistage orifice 1 and the like. There is.

When the pump is started, the on / off valve 14 is "opened", and a part of the high-pressure water discharged by the high-pressure pump 13 is sent to the deaerator 5 through the circulation circuit 7, whereby the start-up operation is started. In this case, the high pressure water flowing through the circulation circuit 7 is reduced to a predetermined pressure by the multistage orifice 1 and then returned to the deaerator 5.

After the pump 13 enters the steady operation in this way, the on / off valve 14 is "closed" and the entire pump discharge amount is supplied to the boiler.

FIG. 4 shows an example of the structure of a conventional multi-stage orifice 01 used for such a water supply line. Orifices 02 having water passage holes 02a are arranged in multi-stages, and each of them is connected at a joint portion 08. The water supply pipe 1 is constructed by welding and coupling couplings 04 are welded to both ends of the row.
0 is welded to both couplings 04 at a joint 09.

[0007]

By the way, as described above, the conventional multi-stage orifice is constructed by welding and joining a plurality of orifices, so that there is a problem that the assembly and installation of the orifices are troublesome and time-consuming. .

Further, when the specifications of the orifices are changed (for example, the number of stages is increased) during operation, it is necessary to once cut and re-weld the welded portion between the orifices, which causes a trouble such as a great deal of trouble. It was

It is an object of the present invention to solve the above-mentioned problems of the conventional apparatus, to significantly reduce the number of welding steps, to assemble and to provide a new multistage orifice in which the installation time is greatly reduced.

[0010]

As a structure for achieving the above object, a multi-stage orifice of the present invention is formed in a cylindrical shape and has a connection portion with a water supply pipe at one end, and is connected to a lower portion inside the cylindrical shape. A seat with water holes is provided, and a plurality of orifices with water holes are placed in the case with screws on the upper part of the inner wall of the case so as to overlap the seat in the case. Further, the cylindrical case has a connection portion with the water supply pipe at the other end thereof, a water passage hole is bored therein, and screwed into a screw engraved on the inside upper portion of the case on the outer periphery of the lower portion thereof. It is characterized in that a coupling having a screw engraved therein is screw-fitted to press the plurality of multi-stage orifices, and then a contact portion between the coupling and an upper edge of the case is welded.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention;

FIG. 1 is a sectional view showing the structure of a multistage orifice according to an example of an embodiment of the present invention. In the figure,
Reference numeral 1 denotes a multi-stage orifice, which is formed in a cylindrical shape and has a connecting portion 3d to which the water supply pipe 10 is connected at one end thereof, and a water passage hole 3a is formed below the inside thereof. A case 3 having a seat 30 formed therein, and a screw 3b formed in the upper part of the inner wall thereof, and a plurality of bowls formed in the shape of a bowl, and water holes 2a formed in the flat portion 2b. Orifice 2
And a connection portion 4d to which the water supply pipe 10 is connected on the upper surface side, and a water passage hole 4a communicating between the connection portion 4d and the lower surface side is bored in the inside thereof, and the case is provided on the outer periphery of the lower portion thereof. Three
It is composed of a coupling 4 and the like in which a screw 4b that fits with the screw 3b is engraved.

When assembling the multi-stage orifice 1, first, the orifices 2 are placed in a predetermined number of stages on the receiving seat 3c provided in the lower stage inside the cylindrical case 3, and then the screws of the coupling 4 are screwed. 4b and the screw 3b of the case 3 are fitted and the orifice 2 is pressed from above by the coupling 4 to fix the position.

After this, the upper edge of the case 3 and the coupling 4
The abutting portion (joint portion 8) with and is welded to complete the assembly.

When the multistage orifice 1 is attached to the water supply pipe (for example, the circulation circuit 7 in FIG. 3), the water supply pipe 10 of the circulation circuit 7 is connected to the connecting portion 3d of the case 3 and the connecting portion 4d of the coupling 4. After the insertion, the joints 9 are welded to complete the process.

Next, when changing the specifications of the multistage orifice 1 attached to the pipe line (changing the water passage hole diameter, changing the number of stages, etc.), first, the welded joints 9 with the water supply pipes 10 at both ends are cut. After removing the multi-stage orifice 1 and then cutting the welded joint 8 and removing the coupling 4 from the case 3, the orifice 2 can be replaced with one having a predetermined hole diameter, or the uppermost orifice 2 can be replaced. After being taken out, as shown in FIG. 2, by inserting a ring-shaped dummy orifice 2'without a flat portion 2b, the number of stages can be reduced, for example, as shown in FIG.
It can be changed from 4 steps shown in to 3 steps.

[0017]

As described above, the multi-stage orifice of the present invention is constructed by stacking a plurality of orifices in a case in multiple stages, tightening the coupling from above, and welding the coupling and the case. Therefore, the number of welding steps is significantly reduced as compared with the conventional product, and the assembly and installation time is shortened.

Further, there is an effect that it is possible to easily change the specifications of the orifice (change of water passage hole diameter, number of stages) during operation.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a multistage orifice according to an example of an embodiment of the present invention.

FIG. 2 is a configuration diagram of a dummy orifice of the same orifice.

FIG. 3 is a water supply circuit diagram for a boiler to which the present invention is applied.

FIG. 4 is a configuration diagram of a conventional multistage orifice.

[Explanation of symbols]

 1 Multistage Orifice 2 Orifice 2'Dummy Orifice 2a, 3a, 4a Water Passage Hole 2b Flat Part 3 Case 3b, 4b Screw 3c Catch 3d, 4d Connection Part 4 Coupling 5 Deaerator 6 Water Supply Circuit 7 Circulation Circuit 8, 9 Welded joint 10 Water supply pipe 13 High pressure pump 14 On / off valve

Claims (1)

[Claims] 1. A receiving seat, which is formed in a cylindrical shape, has a connecting portion with a water supply pipe at one end, and a water passage hole is formed in a lower portion of the cylindrical inner portion, and a screw is formed on an upper portion of an inner wall of the receiving seat. In the provided case, a plurality of orifices each having a water passage hole are placed on the receiving seat in the case so as to overlap with each other, and at the other end of the cylindrical case, there is a connecting portion with the water supply pipe. Then, a water passage hole is bored in the inside of the case, and a coupling in which a screw to be screwed with the screw engraved in the upper part of the case is engraved on the outer periphery of the lower part is screw-fitted to press the plurality of multistage orifices. After that, the multi-stage orifice is constructed by welding the contact portion between the coupling and the upper edge of the case.