Selective catalytic reduction (SCR) system, catalytic silencer of system and welding method for catalytic silencer

Abstract

The invention discloses a catalytic silencer and a welding method for the catalytic silencer. The catalytic silencer comprises a shell and a porous pipe arranged in an inner cavity of the shell. The porous pipe is communicated with a transition connecting disc located on the outer side of the shell. A front end cover is further arranged on the front side of the shell, connected with the wall of the inner end of the shell and welded to the transition connecting disc. The porous pipe is welded to the front end cover and / or the transition connecting disc, so that single-point supporting of the transition connecting disc through the front end cover is optimized to be multi-point supporting, and accordingly the fatigue life of the catalytic silencer is greatly prolonged. The invention further discloses a selective catalytic reduction (SCR) system comprising the catalytic silencer.

Description

technical field [0001] The invention relates to the technical field of engines, in particular to an SCR system and its catalytic muffler and a welding method for the catalytic muffler. Background technique [0002] The SCR system is mainly divided into three parts according to the function: the control unit, the urea dosage unit and the catalytic muffler. Among them, the urea aqueous solution and the tail gas undergo hydrolysis and pyrolysis reactions in the catalytic muffler, and the generated ammonia and tail gas undergo a catalytic reduction reaction on the carrier in the catalytic muffler, and the NO X Reduction to nitrogen, so that the diesel engine exhaust meets emission regulations. Therefore, in the SCR system, the catalytic muffler plays a vital role, and its life determines the life of the SCR system to a certain extent. At present, when the catalytic muffler is assembled, all parts are welded together in a certain order. [0003] A typical catalytic muffler and...

AI Technical Summary

Problems solved by technology

[0009] In the catalytic muffler formed by welding according to the above process, such as image 3 As shown, the transition connection plate 3' is only welded with the front end cover 8', and the two form a single point support cantilever structure. During the working process of the catalytic muffler, the load transmitted by the transition connection plate 3' is all borne by the front end cover 8', resulting in The front end cover 8' deforms greatly, and under the action of alternating loads, cracks occur, resulting in a low fatigue life of the front end cover

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