Friction and wear behavior of different seal materials under water-lubricated conditions

Abstract

The shaft mechanical face seal in a high-speed turbopump of a liquid rocket engine often operates under extremely harsh conditions. For example, a low-temperature and low-viscosity fluid (such as liquid oxygen or liquid hydrogen) is used as a lubricant. The performance of the seal rings, especially the friction and wear behavior, directly determines whether the seal functions normal. In this study, the friction and wear behavior of several ring materials are tested using a pin-on-disk tribo-tester, and the wear morphology of the ring is investigated. The friction coefficients (COFs) and mass-wear rates under dry-friction and water-lubricated conditions, which are used to simulate low-viscosity conditions, are obtained. The results show that at a pressure-velocity (PV) value of 2.4 MPa•(m/s), the COF between the copper graphite (stator) and copper-chrome alloy disk (rotor) is low (with a value of 0.18) under the dry-friction conditions, and the 5-min wear mass of the copper graphite is approximately 2 mg. Under the water-lubricated conditions, compared with other materials (such as copper-chrome alloy, S07 steel, alumina ceramic coating, and nickel-based calcium fluoride), the S07 steel with a diamond-like carbon film is preferred for use in a high-speed turbopump under extreme conditions. The results of this study can provide theoretical and experimental guidance in the design of mechanical face seals in liquid rocket engines.

Tribological Properties of Al2O3/Graphite-Al2O3 Laminated Composites under Water Lubrication Conditions

“…al. investigated friction and wear behaviors of different sealing materials under water-lubricated conditions and found that the pairing of metal-based graphite materials and diamond coating materials was a reasonable combi-nation of sealing materials under both dry friction and water-lubricated conditions [21]. Thirdly, water has a low viscosity and a water-lubricating film is very thin [22] and can be easily destroyed, resulting in high friction or severe wear loss when solid-solid contact occurs in suspended and sediment particle environments.…”

Influence of surface structure on friction and wear characteristics of silicone rubber for hydraulic rod seals

“…1 Consequently, numerous studies have been conducted to investigate the influence of surface roughness on lubrication mechanisms and friction characteristics of rod seals. 2–5…”

“…1 Consequently, numerous studies have been conducted to investigate the inuence of surface roughness on lubrication mechanisms and friction characteristics of rod seals. [2][3][4][5] Feng et al reported that the surface roughness of the counter material, a stainless steel plate, signicantly affects the friction and wear behavior of elastomers when the rubber cylinder slides on the rough surface under lubricated conditions. 6 Scaraggi et al proposed a multiscale mean eld model using the average eld theory to analyze the effect of anisotropic surface roughness on rod seal friction.…”

Evaluation on frictional performance of three different oil-lubricated impregnated graphite seal rings for aircraft integrated drive generators

“…Tribological behaviors of various impregnated graphite materials have been fully investigated under different lubrication regimes to explore the application feasibility in bearings and seals [21,22]. Although the mechanical strength of the impregnated graphite materials is improved, the self-lubricating characteristics are still retained through the migration of graphite and the formation of graphite transfer film on the frictional interface [23].…”