Wesco Valve and Manufacturing Company provides quality power engine valves for almost any application. Even though dimensional conformity to the latest available O.E.M. prints is strictly enforced, Wesco has found it necessary to offer a variety of material content to accomodate many different conditions that affect engine valve life and performance.

Purpose of Valves

Power valves in a four-stroke cycle engine are used to admit fuel and air into the combustion chamber and release burnt gases after combustion. They are used in conjunction with the rest of the valve train to do this at precisely the correct time to allow efficient operation, and at the same time, seal the intake and exhaust ports during combustion.

Alloy Selection for Valves

Proper selection of materials for spark and compression ignition engine exhaust valves depends on four major factors:

Operating temperature is the most critical. An increase in temperature will cause a reduction in the mechanical properties and an increase in the corrosion rates of valve alloys.

Total stress state -- including thermal and cyclic stress effects -- dictates the strength, fatigue, and creep properties a valve must have at a given operating temperature.

Because the exhaust valve functions as a high-temperature gas seal, the corrosivity of exhaust gases and the abrasiveness of solid combustion residues influence the types of corrosive attack and wear an exhaust valve must withstand. Critical contacting interfaces are as follows: The valve face/cylinder head, valve stem/valve guide, and valve tip/rocker arm. Excessive wear at any of these locations can cause valve failure.

Types of Valves

Standard Valve: 4140 stem, 21-12N head
Premium Valve: 4140 stem, 21-12N head with Stellite® #6 inlaid on seating area of valve
Tribaloy® Valve: 4140 stem, 21-12N head with Tribaloy® inlaid on seating area of valve -- takes less oil to reduce wear; for clean or lean burn engines
Inconel® Valve: 4140 stem, inconel head, used in extremely high heat service

Other alloys are available (by special order) for extreme service applications.


© 2001 Wesco Valve & Manufacturing Company - All rights reserved
Stellite® and Tribaloy® are registered trademarks of Deloro Stellite Company, Inc. Inconel® is a registered trademark of International Nickel Corp. Erie® is a registered trademark of Erie Press Systems.