P/M High-Speed Steels for Valve Seat Insert Application

2001 ◽  
Author(s):  
L. Salgado ◽  
F. Ambrozio Filho ◽  
R. M. Leal Neto ◽  
J. L. Rossi ◽  
M. A. Colosio ◽  
...  
Keyword(s):  
High Speed ◽  
Valve Seat ◽  
Seat Insert

Machining and Mechanical Characterisation of PM Materials for Valve Seat Inserts

2005 ◽  
Vol 498-499 ◽  
pp. 79-85 ◽  
Author(s):  
E.S. Jesus Filho ◽  
Lucio Salgado ◽  
S.L. de Jesus ◽  
J.L. Rossi ◽  
Marco Antonio Colosio ◽  
...  
Keyword(s):  
Cutting Forces ◽  
High Speed ◽  
High Speed Steel ◽  
Hard Metal ◽  
Commercial Application ◽  
Valve Seat ◽  
Mechanical Characterisation ◽  
New Development ◽  
Valve Seat Inserts ◽  
Seat Insert

This article shows some fabrication aspects related to the obtention of sintered valve seat insert. This insert was made of a mixture of high-speed steel powders and iron powders plus NbC. This is a new development aiming the substitution of Co alloys currently used for valve seat inserts. The physical properties, mechanical properties and machining behaviour are discussed. The machining characteristics in terms of tool wear, cutting forces and chips morphology of the insert was compared to available commercial insert. The machining results indicate that the material under development has potential for commercial application and shows good machining evidences, in terms of equivalent cutting forces for ceramic tool. In addition, the machining using hard metal tool was susceptible to hardness variation observed for the material under development. Therefore, the machining tests point out the necessity for a microstructure homogenisation of the obtained material.

Study of air quenching influence on valve seat insert obtained with AISI M2 high-speed steel

2017 ◽  
Author(s):  
Igor Passos dos Santos ◽  
Camila Couto ◽  
Luis Augusto Mendes dos Reis ◽  
Cristiano Stefano Mucsi ◽  
Jesualdo Luiz Rossi ◽  
...  
Keyword(s):  
High Speed ◽  
High Speed Steel ◽  
Valve Seat ◽  
M2 High Speed Steel ◽  
Seat Insert

Research on Wear Surface Morphology of PCBN Tools in High-Speed Machining Valve Seat Insert

2014 ◽  
Vol 800-801 ◽  
pp. 155-159 ◽  
Author(s):  
Zhi Ding ◽  
Jiang Han ◽  
Hai Dong Yang
Keyword(s):  
Tool Wear ◽  
Surface Morphology ◽  
Wear Surface ◽  
High Speed ◽  
Main Tool ◽  
Valve Seat ◽  
Digital Microscope ◽  
Series Of Experiments ◽  
Seat Insert ◽  
Pcbn Tools

A series of experiments was conducted in high speed dry turning of valve seat insert with PCBN cutters. The main tool wear surface morphology was observed by utilizing scanning electron microscopy and digital microscope. The experimental results indicate that the tool wear surface morphology is rake face wear, flank wear, chipping, flaking and breakage.

An Experimental Study on Opening Delay of a Reed Valve for Reciprocating Compressors

2011 ◽  
Author(s):  
Fumitaka Yoshizumi ◽  
Yasuhiro Kondoh ◽  
Kazunori Yoshida ◽  
Takahiro Moroi ◽  
Masakazu Obayashi ◽  
...  
Keyword(s):  
High Speed ◽  
Gas Flow ◽  
Valve Seat ◽  
Film Rupture ◽  
Air Conditioners ◽  
Oil Film ◽  
Gas Compression ◽  
Valve Opening ◽  
Reed Valve ◽  
Opening Process

Automatic reed valves are widely used to control refrigerant gas flow in reciprocating compressors for automotive air conditioners. The oil film in the clearance between the reed and the valve seat causes a delay in opening of the valve. This opening delay of the discharge valve leads to over compression, which increases losses such as friction in sliding components and gas overheating. Therefore it is important to understand the behavior both of the oil film and the elastic reed deformation in order to reduce losses due to the delay. This study aims to develop an experimental setup that enables simultaneous visualization of the oil film rupture and measurement of the reed deformation, and to observe this behavior during the valve opening process. The gas-compression stroke is simulated by controlling compressed air with an electromagnetic valve. The oil film rupture is visually observed using a high speed camera through a special valve seat made of glass. The total deformation of the cantilever reed is identified by multipoint strain measurement with 12 strain gauges. The experiment finds that the opening process is divided into four stages. In the first stage, the reed remains stuck to the seat and deforms while the bore pressure increases. In the second stage, cavitation occurs in the oil film and the film starts to rupture. In the third stage, the oil film ruptures and the bore pressure starts to decrease. Finally, in the fourth stage, the reed is separated from the seat and the gas flows through the valve. Reducing the reed/seat contact area changes the reed deformation in the first stage, thereby increasing the reed/seat distance and realizing an earlier oil film rupture and a shorter delay.

Development of Exhaust Valve Seat Insert Material of the Eco-friendly Engine

2003 ◽  
Vol 2003.11 (0) ◽  
pp. 241-242
Author(s):  
Teruo TAKAHASHI ◽  
Arata KAKIUCHI ◽  
Kenichi SATO
Keyword(s):  
Exhaust Valve ◽  
Valve Seat ◽  
Seat Insert

Sintered Valve Seat Inserts – Microstructural Characterisation

2006 ◽  
Vol 530-531 ◽  
pp. 65-70 ◽  
Author(s):  
E.S. Jesus Filho ◽  
Edilson Rosa Barbarosa Jesus ◽  
Lucio Salgado ◽  
S.L. Jesus ◽  
Marco Antonio Colosio ◽  
...  
Keyword(s):  
Heat Treatment ◽  
High Speed ◽  
Diffusion Mechanism ◽  
High Speed Steel ◽  
Heat Treatment Condition ◽  
Commercial Application ◽  
Valve Seat ◽  
Before And After ◽  
The Matrix ◽  
Valve Seat Inserts

This work presents aspects related to new sintered materials for valve seat inserts application. Two types of materials were evaluated. The materials were made using powder metallurgy technique from a basic mixture of high-speed steel (AISI M3/2), iron and carbide powders. The microstructures of these materials before and after heat treatment are presented. Under the heat treatment condition, the activation of the diffusion mechanism among phases was promoted and a better distribution of the Cu phases along the matrix was achieved. The results indicate that the materials under development have a potential for commercial application as valve seat inserts.

scholarly journals High Performance Valve Seat Materials for CNG Powered Combustion Engines

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4860
Author(s):  
Andrzej Romański ◽  
Elżbieta Cygan-Bączek
Keyword(s):  
High Speed ◽  
High Performance ◽  
Base Material ◽  
High Speed Steel ◽  
Wear Test ◽  
Gas Temperature ◽  
Valve Seat ◽  
Test Procedures ◽  
Gasoline Engines ◽  
Engine Valves

The conventional copper infiltrated high speed steel (HSS) valve seats used in gasoline engines are not suitable for CNG combustion because the exhaust gas temperature is at least 80 °C higher, which drastically shortens the service life of the engine valves. Therefore, a proprietary high-alloy HSS-base material was designed to combat hot corrosion and mechanical wear of valve seat faces in CNG fuelled engines. A batch of −100 mesh water atomized HSS powder was commissioned. The powder was vacuum annealed in order to reduce oxygen content and increase its compressibility. To improve the final part machinability, 1.2% MnS was admixed to the HSS powder prior to compaction. The green compacts were sintered at 1135 °C in nitrogen to around 83% TD and subsequently infiltrated with a copper alloy. After installing the valve seat components on a cylinder head, the engine was tested for 100 h according to the automotive industry valve seat wear test procedures. Both the periodic 8-h checks as well as the final examination of the valve seats showed very slow wear, indicating their suitability for CNG powered engines.

scholarly journals Sliding Wear Study on the Valve-Seat Insert Contact

2017 ◽  
Vol 07 (02) ◽  
pp. 42-49 ◽  
Author(s):  
Edgar E. Vera-Cardenas ◽  
Roger Lewis ◽  
Tom Slatter
Keyword(s):  
Sliding Wear ◽  
Valve Seat ◽  
Seat Insert
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