CN203347897U - SCR urea nozzle - Google Patents

Abstract

The utility model discloses an SCR urea nozzle which comprises a urea conveying pipe. A urea spraying head is installed on the front end portion of the urea conveying pipe, a nozzle joint is installed on the back portion of the urea conveying pipe, a mixed cavity communicated with the urea conveying pipe is formed in the urea spraying head, atomization mixing of compressed air and a urea solution is facilitated, the urea spraying head is in a column shape with the thin front and the thick back, a urea spraying hole communicated with the mixed cavity is formed in the front end face of the urea spraying head, the spraying direction of the spraying hole and the number of spraying holes are better matched with the structure of an integrated SCR catalytic muffler, the phenomenon that urea crystallization blocks the urea nozzle is effectively avoided, a thermal insulation sleeve with a through hole in the side portion is installed in a sleeved mode at the position where the urea conveying pipe is connected with the urea nozzle, and the SCR urea nozzle has the thermal insulation and thermal dissipation effects. A nozzle installation base which is installed on the urea conveying pipe in a sleeved mode is installed on the back portion of the thermal insulation sleeve, and the SCR urea nozzle is convenient to install, simple in structure, not prone to blockage, and good in atomization effect.

Description

A SCR urea nozzle

technical field

The utility model relates to an SCR urea nozzle.

Background technique

Selective Catalytic Reduction (SCR) is currently recognized as one of the most effective post-treatment technologies for reducing NO _x emissions from diesel engines. Urea SCR sprays a certain amount of urea aqueous solution into the exhaust pipe, and the urea aqueous solution is evaporated. The pyrolysis and hydrolysis process obtains the reducing agent NH ₃ , and NH ₃ selectively reduces NO _x to N ₂ under the action of the catalyst, thereby reducing the content of NO _x in the exhaust gas. The SCR urea nozzle urea in the prior art There is no mixing chamber at the end of the delivery pipe, which is not conducive to the atomization and mixing of compressed air and urea solution. The opening direction and number of openings on the urea nozzle do not match the structure of the integrated SCR catalytic muffler. The urea droplets are easy to hit the wall and cause Urea crystallizes, and the urea nozzle is arranged on the exhaust pipe. Due to the high temperature in the exhaust pipe, too high temperature will cause the urea in the urea delivery pipe to gasify prematurely, which will affect the spraying effect of the nozzle after long-term accumulation. Clogged nozzle.

Utility model content

The technical problem to be solved by the utility model is to provide an SCR urea nozzle which is convenient for the atomization and mixing of compressed air and urea solution, prevents urea crystallization and is easy to install.

In order to solve the above technical problems, the utility model includes a urea delivery pipe, the front end of the urea delivery pipe is equipped with a urea spray nozzle, and the rear part of the urea delivery pipe is equipped with a nozzle joint. There is a mixing chamber connected with the urea delivery pipe. The urea nozzle is cylindrical with a thin front and a thick rear. A urea spray hole is provided on the front end of the nozzle to communicate with the mixing chamber. The connection between the urea delivery pipe and the urea nozzle is fitted with a A heat sleeve, the rear of the heat insulation sleeve is equipped with a nozzle mounting seat sleeved on the urea delivery pipe.

A cavity is provided between the heat-insulating sleeve and the urea delivery pipe, and the side of the heat-insulation sleeve is provided with a vent hole communicating with the cavity to ensure that the urea delivery pipe has better heat dissipation performance and avoid the urea delivery pipe from being damaged. Thermal expansion causes certain pressure on the structure of the urea nozzle.

The upper part of the nozzle mounting seat is provided with a groove for the installation of the heat insulation sleeve, the middle front side of the nozzle mounting seat is provided with a through hole for the urea delivery pipe to pass through, and the two sides of the lower part of the nozzle mounting seat are respectively provided with mounting holes. Holes for easy installation of nozzle mounts.

Compared with the prior art, the SCR urea nozzle adopting the above scheme has the following advantages: the front end of the urea nozzle is provided with a urea injection hole, and the injection direction and number of the injection holes match well with the structure of the integrated SCR catalytic muffler. Effectively avoid the phenomenon of urea crystallization blocking the urea nozzle. The mixing chamber in the urea nozzle is conducive to the atomization and mixing of compressed air and urea solution to maintain the continuity of urea spray. High temperature will cause premature gasification of urea in the urea delivery pipe. The urea nozzle is equipped with a urea nozzle seat, which is convenient for installation, and the installation is standardized. The utility model has simple structure, good spray atomization effect, is not easy to block, and improves system stability. .

Description of drawings

Below in conjunction with accompanying drawing, the specific embodiment of the present utility model is described in further detail:

Fig. 1 is the structural representation of the utility model;

Fig. 2 is A-A to sectional view among Fig. 1;

Fig. 3 is a schematic diagram of the structure of the urea nozzle seat.

Detailed ways

As shown in Figures 1 and 2, the SCR urea nozzle includes a urea delivery pipe 1, a urea nozzle 2 is installed at the front end of the urea delivery pipe 1, a nozzle joint 8 is installed at the rear of the urea delivery pipe 1, and the urea nozzle 2 is fixedly connected to the At the front of the urea delivery pipe 1, the urea nozzle 2 is a cylindrical shape with a thin front and a thick rear, and its front end surface is a conical surface, the smaller the conical surface, the better, and a urea spray hole 3 communicating with the urea delivery pipe 1 is provided on it , the area of the end face of the urea injection hole 3 is small, the opening direction and number of openings of the urea injection hole 3 match the structure of the integrated SCR catalytic muffler, which is not easy to cause carbon accumulation, and at the same time, the exhaust flow washes away the carbon accumulation and urea droplets , Effectively prevent urea droplets from clogging the urea injection hole. The urea nozzle 2 is provided with a mixing chamber 9 communicating with the urea delivery pipe 1, and the other end of the mixing chamber 9 is communicating with the urea spray hole 3, which is beneficial to the atomization and mixing of the compressed air and the urea solution, and can effectively promote the crushing and disintegration of the urea droplets. Mixing, atomization effect is good. The connection between the urea delivery pipe 1 and the urea nozzle 2 is fitted with a thermal insulation sleeve 4, and the front end of the thermal insulation sleeve 4 is clamped to the rear end of the urea nozzle 2 to prevent the urea aqueous solution from overheating in the long urea delivery pipe 1. High chemical reactions form polymers to produce local crystallization, a cavity is provided between the heat insulating sleeve 4 and the urea delivery pipe 1, and a vent hole 5 communicating with the cavity is provided on the side of the heat insulating sleeve 4 to ensure the delivery of urea The pipe 1 has a good heat dissipation performance, which prevents the urea delivery pipe 1 from causing a certain pressure on the structure of the urea nozzle due to thermal expansion. As shown in Figure 1 and Figure 3, the rear part of the heat insulation sleeve 4 is equipped with a nozzle mounting seat 7 that is sleeved on the urea delivery pipe 4, and the upper front side of the nozzle mounting seat 7 is provided with a hole for the heat insulation sleeve 4 to install. Groove, the heat insulation sleeve 4 is welded in the groove, the middle part of the nozzle mounting seat 7 is provided with a through hole for the urea delivery pipe 1 to pass through, the urea delivery pipe 1 is welded to the through hole, the two sides of the lower part of the nozzle mounting seat 7 Installing holes are provided respectively, and the nozzle mounting seat 7 is installed on the exhaust pipeline by fastening bolts. The nozzle mounting seat 7 can accurately ensure the installation angle of the urea nozzle, and the installation is simple and convenient, avoiding urea crystallization caused by irregular installation angles.

The utility model is not limited to the above-mentioned specific embodiments, and those skilled in the art can make some changes and modifications without departing from the spirit and scope of the utility model. The protection scope of the utility model should be based on the claims of the utility model.

Claims (3)

1. An SCR urea nozzle, comprising a urea delivery pipe (1), a urea nozzle (2) is installed at the front end of the urea delivery pipe (1), and a nozzle joint (8) is installed at the rear of the urea delivery pipe (1) ), which is characterized in that the urea nozzle (2) is provided with a mixing chamber (9) in communication with the urea delivery pipe (1), and the urea nozzle (2) is cylindrical in shape with a thin front and a thick rear, and its front end is provided with a A urea injection hole (3) connected to the mixing chamber (9), the connection between the urea delivery pipe (1) and the urea nozzle (2) is covered with a heat insulating sleeve (4), and the heat insulating sleeve (4 ) is equipped with a nozzle mounting seat (7) sleeved on the urea delivery pipe (1). 2. The SCR urea nozzle according to claim 1, characterized in that a cavity is provided between the heat insulation sleeve (4) and the urea delivery pipe (1), and the side of the heat insulation sleeve (4) is provided with There is a ventilation hole (5) communicating with the cavity. 3. The SCR urea nozzle according to claim 2, characterized in that the upper front side of the nozzle mounting seat (7) is provided with a groove for the installation of the heat insulating sleeve (4), and the nozzle mounting seat (7) The middle part of the nozzle is provided with a through hole for the passage of the urea delivery pipe (1), and the two sides of the lower part of the nozzle mounting seat (7) are respectively provided with installation holes.

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