Improvement of high pressure oil hole processing technology for diesel engine cylinder head parts

For details of the article, please purchase the 4th issue of Modern Parts in 2007 or the PDF file at the bottom of the download page.

status quo

When the company processed the high-pressure oil hole of the cylinder head of the 6DL diesel engine product, the problem of frequent fracture of the f12.7mm drill bit occurred, resulting in extremely low processing efficiency, even to the point where it could not be produced normally. The process plan at that time was developed by the German company GROB, and the specific processing diagram and process flow are shown in Figure 1.

1. Schematic diagram of processing Figure 1 Schematic diagram of processing 2. Process plan of GROB company in Germany (1) Milling high-pressure oil hole orifice plane (using SANDVIK's f45mm milling cutter, see Figure 2).

(2) Pre-drilling stepped holes of f6mm/f15.5mm/f20.5mm (using the imported company's three-stage step drill, see Figure 3).

(3) Drill a hole of f4.25mm (guarantee center distance 6.5mm) (using the TX drill of the import company, see Figure 4).

(4) Drill the high-pressure oil hole of f6mm/f12.7mm (using the SE step of the imported company with a 6mm centering, see Figure 5).


Analysis <br> <br> After analysis, we believe there are two reasons for the cutting knife:

(1) The stepped drill of f12.7mm is made of cemented carbide. We believe that the f12.7mm drill bit is affected by the processed f4.25mm hole next to it during processing, resulting in intermittent cutting during machining. Phenomenon, due to the poor toughness of the cemented carbide tool and the poor strength of the pilot drill with a head of f6mm, it causes frequent breakage.


the measures taken

In view of the above situation, from another angle, we proposed to simplify the tool structure of the f12.7mm drill bit, change the processing mode of the f4.25mm hole, and determine the machining process plan for the milling and drilling.

New process plan

(1) Milling high pressure oil hole orifice plane (using imported company's f45mm corn milling cutter, Figure 6).

(2) Pre-drilling f15.5mm/f20.5mm holes (using the step drill of the import company, currently using the original, Figure 7).


Effect comparison

The cost per piece before and after improvement is shown in Figure 10 and Figure 11.


Urban leisure Segway, because of its convenience, it can be used in office buildings, fast-moving walkways, parks, factories, hospitals and other establishments. And be adapt to riding in the city's narrow space without worrying about how to park, because of its energy-saving and low-carbon environment, it can highlight the personal cool personality, therefore it is an excellent choice for short-distance personal transport. Free to wander in every corner of the city.

Cross country Segway, which is use of metal fender and large size, damping tire pressure vacuum off-road tire, so it has a large area of touching with the ground, ground friction and lower shaking, Because of having separated gear box, the power can be 10 times increased more than before. So the max speed can be up to 20km/h and climb the 25 degree slope. It is easy to cross the rugged, steep, pit depression, such as topography, geomorphology, and then arrived at any places which ordinary vehicles can not reach it, Drive with your mind and cross any rough places. It has three modes: beginner mode, normal mode, traction mode 8km / h (beginner mode), 20km / h (normal mode), it is easy to go uphill under traction mode.


Seg Way, Segway Scooter, Segway For Kids, Electric Segway, Segway Transporter