LPG & βενζίνη συγκριτική μελέτη φθορών βαλβίδων εξαγωγής

[NIKOSP]

Ενδιαφέρουσα συγκριτική μελέτη για την φθορά από τριβή στις βαλβίδες εξαγωγής, μεταξύ Lpg & Βενζίνης:
Το βασικό συμπέρασμα είναι ότι ζορίζονται κυρίως οι έδρες και κυρίως το μέρος που "βλέπει" προς τον κύλινδρο. Η πιθανολογούμενη αιτία είναι η απουσία καταλοίπων καύσης τα οποία λειτουργούν προστατευτικά παρεμβαλούμενα ανάμεσα στα μέταλλα της βαλβίδας και της έδρας...

Εδώ ο επίλογος από το αγγλικό κείμενο.
Όπου Dmax το βάθος φθοράς:
"The mean Dmax of the exhaust valve and the seat insert, for which the test was performed with LPG fuel, was greater than that of the exhaust valve and the seat insert for which the test was performed with gasoline fuel, 14.5% and 29.4%, respectively. The adhesive wear and tribochemical reaction products were observed regardless as to whether the fuel type was LPG or gasoline. However, the abrasive wear was observed only at the seating face of the seat insert for which the test was performed with LPG fuel. From the analysis performed based on the above results, it is thought that since LPG fuel has less combustion products that act as a gum component that lubricates the valve and the seat insert seating faces than gasoline fuel. The direct metal-to-metal collision between the valve and the seat insert seating faces may generate more particles with LPG fuel. Therefore, The abrasive wear was observed only in the specimen for the test performed with LPG fuel, however it was not observed in the specimen for the test performed with gasoline fuel."


https://link.springer.com/article/10.10 ... 012-0031-5