DESTRUCTION OF MOTOR CAR HIGH-LIFT FUEL PUMP CASING CAUSED BY CORROSION CRACKING
Rubrics: TRANSPORT
Authors:
Type:
Article
Pages:
from 186
to 191
Status:
Published
Received:
07.12.2016
Accepted:
07.12.2016
Published:
07.12.2016
Language:
Russian
Keywords:
high-lift fuel pump, HLFP, inlet valve, compression chamber, destruction, corrosion cracking, plastic deformation
Abstract (English):
The paper reports the state of casing material of motor car highlift fuel pump destructed during operation. With the purpose of the material study on defects existence in the structure there is carried a metallograph analysis of cap material in an inlet valve. The investigation of nonmetal inclusions was carried out in accordance with the requirements of RSS 1778-70. At the same time there was carried out the investigation of a sample microstructure. The analysis of the totality of destruction facts revealed allowed drawing a conclu-sion that a casing destruction in a HLFP took place in the area of a lower turn of cover thread of one of inlet valves. It is established that the destruction occurred as a result of crack formation and its growth. A crack arose in the course of operation as a result of edge brittleness in metal grains caused by the development of corrosion cracking processes development.
The paper reports the state of casing material of motor car highlift fuel pump destructed during operation. With the purpose of the material study on defects existence in the structure there is carried a metallograph analysis of cap material in an inlet valve. The investigation of nonmetal inclusions was carried out in accordance with the requirements of RSS 1778-70. At the same time there was carried out the investigation of a sample microstructure. The analysis of the totality of destruction facts revealed allowed drawing a conclu-sion that a casing destruction in a HLFP took place in the area of a lower turn of cover thread of one of inlet valves. It is established that the destruction occurred as a result of crack formation and its growth. A crack arose in the course of operation as a result of edge brittleness in metal grains caused by the development of corrosion cracking processes development.
Keywords:
high-lift fuel pump, HLFP, inlet valve, compression chamber, destruction, corrosion cracking, plastic deformation
high-lift fuel pump, HLFP, inlet valve, compression chamber, destruction, corrosion cracking, plastic deformation
1. RD 50-672-88. Methodic Indications. Computations and Strength Tests. Classification of Metal Fractures.
2. Fractography and Fractogram Atlas: reference book: [transl. from Engl.]/under the editorship of J.Fellowse. - М.:Metallurgy, 1982.
3. RSS 1778-70. Steel. Metallographic Methods of Non-metal Inclusions Definition.
4. Methods for Metallographic Etching: reference book: [transl. from Germ.]/ М.Bekkert, H.Klemm. - М.: Metallurgy,1988. - pp. 400.
5. Kovalenko, V.S. Metallographic Agents/ V.S.Kovalenko. - М.: Metallurgy, 1973. - pp. 112.
6. Azhogin, F.F. Corrosion Cracking and High-Carbon Steel Protection/ F.F.Azhogin. - М.: Metallurgy, 1974. - pp. 256.
7. Program for Self-Instruction VW 467.
