Presentation is loading. Please wait.

Presentation is loading. Please wait.

TMC ( T echno M aterial C orp.) Cam/Tappet Valve Train Parts : Severe/Abnormal Wear at Cam/Tappet Power Train Parts : Severe/Abnormal Wear at Piston Ring/liner.

Similar presentations


Presentation on theme: "TMC ( T echno M aterial C orp.) Cam/Tappet Valve Train Parts : Severe/Abnormal Wear at Cam/Tappet Power Train Parts : Severe/Abnormal Wear at Piston Ring/liner."— Presentation transcript:

1 TMC ( T echno M aterial C orp.) Cam/Tappet Valve Train Parts : Severe/Abnormal Wear at Cam/Tappet Power Train Parts : Severe/Abnormal Wear at Piston Ring/liner What Happened in Diesel Engines

2 TMC ( T echno M aterial C orp.) Heavy Duty Diesel-Engine Exhaust Gas Regulation It is a Chance of Technologies Advance. EURO1(1992 ) EURO2(1996 ) EURO3(2000) EURO4(2005)  Cam: Induction H Tappet: Hard Metal  Ring: Cr-Ceramic Liner: High Alloy Cast  Cam: Induction H Tappet: ? Ceramic  Ring : ? Cr-Diamond Liner: ? Laser Steel  Cam: Induction H Tappet : Chilled Cast  Ring: Cr Plating Liner: High P-Cast KOREA(2004) KOREA(2006) KOREA(2000) 70Kg/mm^2 160Kg/mm^2 Stress: ?

3 TMC ( T echno M aterial C orp.) Cam and Tappet Movement in Valve Train System Contact between Cam and Tappet Line contact, Rolling with sliding Crowned surface of tappet (for uniform wear) Lubrication Cam Base Area : Hydrodynamic lubrication Cam Nose Area : Boundary lubrication # Nose ± 20°, Max. contact stress, Lubrication film failure  Severe wear occurs Hertzian Contact Stress σ max ∝ [P/WR(1/E1+1/E2)] ½ W = Cam width R = Cam radius P = Max. load σ max =Max. Contact Stress E1/E2 = Young’s modulus of Cam/Tappet

4 TMC ( T echno M aterial C orp.) Valve Train System, OHV Type Diesel Engine Valve timing control Profile of Cam nose will be maintained during engine life Wear of Cam and Tappet  Timing Changed  Imperfect Burning PM and NOx increase in exhaust gas If severe wear occurrs in cam and tappet  Engine Fails

5 TMC ( T echno M aterial C orp.) A case of failure - Tappet Pitting and Cam Scuffing High Hertzian Contact Stress Adhesion of mating materials

6 TMC ( T echno M aterial C orp.) Newly Designed Hard metal tappet - Characteristics I Simple Process –Low Sintering Temperature for WC Tip (1450 =>1050°C) –Direct Bonding of As-Received WC tip and Machined Body High Bonding Strength –Vacuum Atmosphere –High Wettability to Steel –Formation of Diffusion Layer - Main composition : WC with Binder Alloy –WC size : Average 1~5  m Hardness : Above HRA 85 –Bending strength : Average 100 kgf/mm^2 (TRS) –Young’s modulus : 43,000 kg/mm^2 –Thermal conductivity : 0.17 cal/cm sec  C (75W/mK) –Thermal expansion coefficient : 6 x /  C

7 TMC ( T echno M aterial C orp.) Mass Production  Technical Alliance with the T.M.C, High Technology possession enterprise  There’s no Quality Problems in mass production of Hard Metal tappet for 5 years ▶ CUSTOMER & SPECIFICATION OF ENGINE ▶ SUPPLY RECORD OF HARD METAL TAPPET(T.M.C)

8 TMC ( T echno M aterial C orp.) Line contact, Reciprocal sliding with rolling. Measure the rapid increase time of friction coefficient  scuffing time Scuffing occur No Scuffing Wear Test - Scuffing

9 TMC ( T echno M aterial C orp.)  Hard metal tappet have a longer scuffing time than Fe-alloy tappet  3 of 5 case of hard metal tappet have not scuffing during test  Hard metal tappet have a smaller friction coefficient than Fe-alloy tappet  Hard metal tappet have a better anti-scuffing characteristics than Fe-alloy tappet Wear Test - Results

10 TMC ( T echno M aterial C orp.) - Part test of engine, driven by electrical motor - Performed 500 hours, at 2200 crankshaft RPM - Contact stress of cam and tappet is higher than in a real engine - 6 Fe-alloy tappets and 6 hard metal tappets are tested. Rig Test(Motoring) - Pitting - Fe alloy Tappets have pitting & all of them have not shown crowned shape - Hard Metal tappets have no pitting & remain crowned shape

11 TMC ( T echno M aterial C orp.) To test the Reliability of Engine parts  E ngine Dynamo Test : 1,000 hour, 2200 RPM - Fe alloy tappets have pitting (2 of 6) & Not scuffing - Hard metal tappets have no pitting and no scuffing  Field Test : 100,000km - Bus and Truck mounting, Only hard metal tappet test. - No pitting and No scuffing - Crowned shape of tappet is remained. - The surface of Tappet and cam were fine-polished. - It means that it is possible to use the tappets again. - There’s no wear problem after applying in the field for nearly 5 years Dynamo Test & Field Test

12 TMC ( T echno M aterial C orp.) Reliability of Tappet Bonding  Ultrasonic test of bonded parts  Last 3 years, mass production of Hard Metal tappet, There’s no apart of bonded part.  Quality assurance system of tappet produced, it has a reliabilities


Download ppt "TMC ( T echno M aterial C orp.) Cam/Tappet Valve Train Parts : Severe/Abnormal Wear at Cam/Tappet Power Train Parts : Severe/Abnormal Wear at Piston Ring/liner."

Similar presentations


Ads by Google