tailieunhanh - Volume 18 - Friction, Lubrication, and Wear Technology Part 24

Tham khảo tài liệu 'volume 18 - friction, lubrication, and wear technology part 24', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | destruction of interfacial junctions on a microscopic scale. This is often the basic cause. The period depends on the velocity and on the elastic characteristics of the system. Stick-slip will not occur if the static friction is equal to or less than the dynamic friction. The motion resulting from stick-slip is sometimes referred to as jerky motion Ref 1 . See also spragging . stiction A term sometimes used to signify the condition in which the frictional resistance is sufficient to prevent macroscopic sliding Ref 1 . Stoke centistoke The centimeter-gram-second cgs unit of kinematic viscosity Ref 1 . storage stability A measure of the ability of a lubricant to undergo prolonged periods of storage without showing any adverse conditions due to oxidation oil separation contamination or any type of deterioration Ref 5 . Stribeck curve A graph showing the relationship between coefficient of friction and the dimensionless number . N P where is the dynamic viscosity N is the speed revolutions per minute for a journal and P is the load per unit of projected area. Note The symbols Z and v linear velocity may be substituted for . and N respectively Ref 1 . Stribeck curve coefficient of friction and type of lubrication versus dimensionless variable - ỈN P sulfochlorinated lubricant A lubricant containing chlorine and sulfur compounds which react with a rubbing surface at elevated temperatures to form a protective film. Note There may be a synergistic effect producing faster reaction than with sulfur or chlorine additives alone Ref 1 . sulfurized lubricant A lubricant containing sulfur or a sulfur compound that reacts with a rubbing surface at elevated temperatures to form a protective film. Note The shear strength of the sulfide film formed on ferrous materials is lower than that of the metal but greater than that of the film formed by reaction with a chlorinated lubricant Ref 1 . superficial hardness test See Rockwell superficial hardness test . surface damage In tribology .