1、GM DAEWOO Auto & Technology EDS Engineering, GM DAEWOO Auto & Technology Standards THE MEASURING METHOD OF INDUCTION HARDENING DEPTH AND HARDENSS FOR CAMSHAFT EDS-T-7177 ISSUED DATE: 1998. 03. 29 REVISED DATE: 2006. 06. 19 VERSION: 2 EDS-T-7177THE MEASURING METHOD OF INDUCTION HARDENING DEPTH AND HA
2、RDENSS FOR CAMSHAFT PAGE: 1/3 ISSUED DATE: 1998. 03. 29 REVISED DATE: 2006. 06. 19 VERSION: 2 GM DAEWOO Auto & Technology 1. PURPOSE This standard aims at helping test engineers conduct test in a correct and easy manner by specifying the method of measuring induction hardening depth and hardness of
3、the cam shaft. 2. SCOPE This standard specifies the method of measuring induction hardening depth and hardness of the induction-hardened cam shaft. 3. DEFINITION OF TERMS 3.1. Induction hardening Hardening of the steel or cast iron surface by rapid heating with high frequency induction current and e
4、nsuing rapid cooling 4. TEST PIECE 4.1. As shown in Fig 1, cut sections “A-A“ and “B-B“ in the direction of shaft diameter with a cutting machine to get a lobe from the cam shaft. 4.2. In cutting with a cutting machine, sufficient amount of cutting oil shall be applied and the cutting speed shall be
5、 appropriate to avoid over-heating of the test piece. Too fast cutting may cause over-heating even with sufficient amount of cutting oil. 4.3. The cut lobe shall be indicated as follows: 4.3.1. Lobes shall be numbered from the cam shaft front. 4.3.2. For each lobe, the front side nose shall be marke
6、d “a“ and the opposite “b“. (See Fig 3.) 4.3.3. For each lobe, the rear side nose shall be marked “c“ and the opposite “d“. (See Fig 3.) 4.4. Upon completing marking, cut each lobe as shown in Fig 2. In cutting, be sure to avoid over-heating of the test piece as mentioned in clause 2. 4.5. While bot
7、h cut surfaces may be used for measuring, precise half sections shall be used to avoid errors. Sharp edges formed during casting and cutting shall be removed with a grinder. 4.6. Each cut section shall be ground until becoming a mirror surface and subsequently corroded for some time by 5% NITAL solu
8、tion until the hardened part and core part are clearly identified. EDS-T-7177THE MEASURING METHOD OF INDUCTION HARDENING DEPTH AND HARDENSS FOR CAMSHAFT PAGE: 2/3 ISSUED DATE: 1998. 03. 29 REVISED DATE: 2006. 06. 19 VERSION: 2 GM DAEWOO Auto & Technology Fig 1. How to cut out lobe from shaft body Fi
9、g 2. How to cut out inspection section from cut lobe Fig 3. Hardening pattern and measuring points of section C-C (Fig 2) 5. MEASURING METHOD 5.1. Induction hardening depth measuring 5.1.1. Measure the thickness of the etched induction hardening layer with a tool-makers microscope or a EDS-T-7177THE
10、 MEASURING METHOD OF INDUCTION HARDENING DEPTH AND HARDENSS FOR CAMSHAFT PAGE: 3/3 ISSUED DATE: 1998. 03. 29 REVISED DATE: 2006. 06. 19 VERSION: 2 GM DAEWOO Auto & Technology microscope with scales. Measuring points shall be a, b, c and d of each lobe as shown in fig 3. 5.1.2. Enter the lobe no. and
11、 measuring points in the report after measuring. 5.2. Hardness measuring 5.2.1. Finished camshaft Measure the hardness of the lobe with a Rockwell C-scale across the nose of the lobe in the method specified below: (1) At measuring, the base circle of the lobe shall be supported on the “V-shape” anvi
12、l. (2) The phosphate coating shall be removed in the manner that will not affect the base metal, such as light buffing or sanding. Hardness may be measured before phosphate coating process. (3) Measure the hardness at 3 points, or the center of the lobe nose and 3mm inward from each edge, and get th
13、e mean value of measurements. (4) The measured hardness shall be corrected according to the radius of curvature of the lobe. In case a hardness tester with an automatic correcting function is used, measurement shall be made after input of the radius of curvature (Check the radius of curvature specif
14、ied in drawings). 5.2.2. Half-finished camshaft For the half-finished camshaft, measuring shall be performed as above after the semi-processed lobe is induction hardened. The limits of the half-finished camshaft shall be so set as not to run counter to the specifications of the finished camshaft. 6.
15、 INDICATION 6.1. The hardening depth shall be expressed in mm. 6.2. Unless specified otherwise, the result of hardening depth measuring shall be rounded off to the first decimal point according to KS A 0021(Rounding-off of figure). 6.3. The result of surface hardness measuring shall be rounded off t
16、o the first decimal point according to EDS-T-7117 (Test with Rockwell hardness tester). 7. RELATED STANDARDS EDS-T-7110 Flame and induction hardening depth measuring of steel 8. REFERENCE CA 001-04 (FORD laboratory test method): Depth of induction hardening and hardness of camshaft and auxiliary shaft
