CN1202570A - Tail gas purifying silencer for internal combustion engine - Google Patents

Abstract

The tail gas purifying silencer uses catalyst carrier made of foam metal material. Compared with available catalyst carrier, the foam metal catalyst carrier is superior in strength and hot stress impact resistance as well as excellent machining property and tail gas noise reducing property, and this makes the silencer easy to make and install and long in service life.

Description

Tail gas purifying silencer for internal combustion engine

The present invention relates to a kind of tail gas purifying silencer for internal combustion engine that adopts the foamed metal catalyst carrier.

At present, exhaust gas purifier for IC engine adopts ceramic honey comb as catalyst carrier more both at home and abroad, its carrier surface is impregnated with catalyzer, purification process is: the tail gas that produces during internal combustion engine enters in the purifier by the suction port of purifier, when tail gas passes through catalyst carrier, redox reaction can take place in the CO in the tail gas, hydrocarbon, nitrogen oxide under the supported catalyst effect, generate CO ₂, water and nitrogen, enter the atmosphere from the air outlet, thereby reduce the harm of tail gas environment.But, have following deficiency owing to adopt ceramic honey comb as catalyst carrier:

1, intensity is not high, and is very crisp, poor seismic behavior.Can be broken when on vehicle, using because of the vibrations of jolting of car body, make exhaust purifier lose efficacy, for remedying the deficiency of this respect, existing exhaust purifier also must install special shock insulation liner additional around catalyst carrier, but the anti-seismic performance of exhaust purifier is still undesirable, and cost increases;

2, the thermal stress resistance impact property is poor.Because vehicle is from start to travelling, the temperature of exhaust purifier skyrockets, and can cause the inlet, outlet two ends temperature of catalyst carrier variant, because the fragility of pottery itself, can cause the catalyst carrier non-homogeneous expansion and crack, fragmentation, exhaust purifier was lost efficacy;

3, ceramic honey comb material matter is crisp, can not carry out conventional machining, and the production difficulty increases;

4, do not have tangible noise elimination effect.

Although existing exhaust purifier also has other kind, as with Al ₂O ₃Bead as catalyst carrier, that adopt catalyst case, with stainless-steel sheet as catalyst carrier, or the like, but preparation process is all comparatively complicated, and cost is higher.

The purpose of this invention is to provide that a kind of its intensity is big, the thermal stress resistance impact capacity is superior and have good machinability and reduce tail gas noise function, be convenient to processing and fabricating and installation, the tail gas purifying silencer for internal combustion engine of long service life.

The objective of the invention is to adopt the exhaust gas purifier for IC engine made with the foamed metal catalyst carrier to realize, this foam metal can be foam aluminium alloy or foam copper alloy.

The present invention compared with prior art has following advantage:

1, catalyst carrier intensity increases, and exhaust purifier can be not broken because of the vibrations of jolting of car body, need not install special shock insulation liner additional during installation around catalyst carrier;

2, the thermal stress resistance impact property strengthens, and catalyst carrier can be because of not advancing, and the variant and non-homogeneous expansion of the temperature at the two ends of giving vent to anger cracks, fragmentation;

3, have good machinability, can be processed into different size shapes as required;

4, have tangible noise elimination effect, make tail gas sound source noise reduce by 3～5dB, and do not increase oil consumption.

Fig. 1 is the structural representation that the present invention adopts one group of foamed metal catalyst carrier embodiment;

Fig. 2 is the structural representation that the present invention adopts two groups of foamed metal catalyst carrier embodiments;

The invention will be further described below in conjunction with accompanying drawing:

Among Fig. 1: 1-suction port

2-clamp flange

3-housing

4-foamed metal catalyst carrier

5-clamp flange

6-air outlet

Test one: the present invention is used for car Santana (adopting one group of foamed metal catalyst carrier), catalyst carrier adopts foam aluminium alloy, catalyst component is existing catalyst component, when tail gas passes through tail gas purifying silencer for internal combustion engine, can reach following index:

1, initial operating temperature: 170～200 ℃;

2, operating temperature range: 270～700 ℃, and when maximum temperature, catalyst carrier does not produce sintering phenomenon, does not reduce purifying effect;

3, use idling method of measurement (GB/T3845-93), meet under the prerequisite of light-duty vehicle tailpipe emission standard (GB14761.1-93) engine idle purification ratio: CO＞90% more than 270 ℃, CH＞85% at automobile;

4, use light-duty vehicle exhaust contaminant test method (GB11642), under the prerequisite that meets light-duty vehicle tailpipe emission standard (GB14761.1-93) at automobile, during operating temperature, make the harmful gas (comprising CO, CH and NOx) more than 70% become harmless CO more than 270 ℃ ₂, water and nitrogen;

5, working life: more than 50,000 kilometers;

6, reduce tail gas sound source noise 3～5dB, oil consumption does not increase substantially.

Adopt foam copper alloy as catalyst agent carrier to do above-mentioned test, its test result and foam aluminium alloy catalyst carrier are basic identical.

Fig. 2 and Fig. 1 similar, difference only is to be provided with two groups of foamed metal catalyst carriers.

Test two: the present invention is used for car Santana (adopting two groups of foamed metal catalyst carriers), catalyst carrier adopts foamed aluminium, catalyst component is existing catalyst component, just be impregnated with the catalyst component that makes decompose nitrogen oxides on first group of catalyst carrier, be impregnated with the catalyst component that makes CO, oxidizing hydrocarbon on second group of catalyst carrier, when tail gas passes through tail gas purifying silencer for internal combustion engine, except that wherein nitrogen hydride composition slightly descended than embodiment 1, other index was substantially the same manner as Example 1.

Adopt foam copper alloy as catalyst agent carrier to do above-mentioned test, its test result and foam aluminium alloy catalyst carrier are basic identical.

Claims (2)

1, a kind of tail gas purifying silencer for internal combustion engine is characterized in that: catalyst carrier adopts foam metal material to make.

2, tail gas purifying silencer for internal combustion engine as claimed in claim 1 is characterized in that: foam metal can be foam aluminium alloy or foam copper alloy.