Experimental Study on Rubbing Wear Characteristics of Labyrinth Seal with Trapezoidal Fins

2021 ◽  
pp. 1-42
Author(s):  
Xin Yan ◽  
Xinbo Dai ◽  
Kun He
Keyword(s):  
Mass Loss ◽  
High Speed ◽  
Wear Behavior ◽  
Early Stage ◽  
Labyrinth Seal ◽  
Contact Forces ◽  
Sliding Velocity ◽  
Wear Performance ◽  
Wear Characteristics ◽  
Geometrical Effect

Abstract The wear characteristics of trapezoidal fin against high speed rotor were experimentally investigated at different final incursion depths, incursion rates, and sliding velocities. To characterize the geometrical effect, a small specimen (SS) and a large specimen (LS) were selected to analyze the mass loss, wear geometry, contact forces, and frictional temperature distributions under different conditions. The results show that the contact-separation is most likely to occur between the trapezoidal fin and rotor. In the rubbing process, the plastic deformation is dominating, and the abrasive and adhesive wears have pronounced effects on the wear behavior of rubbing interface. The wear performance of the SS is sensitive to the structure imbalance, which induces the combined mushrooming and bending damage in the trapezoidal fin. However, the symmetrical mushrooming damage is generated in the LS. For both SS and LS, the mass loss is decreased with increasing the incursion rate and sliding velocity, and the mass loss percentage is pronounced at the early stage of rubbing. The averaged friction coefficient is 0.1-0.16 for the LS, while 0.1-0.19 for the SS. The peak frictional temperature is 560-640 °C for the LS, while 360-400 °C for the SS. The contact-separation significantly reduces the effects of final incursion depth, incursion rate, and sliding velocity on the wear geometry, contact forces and temperature rise in the trapezoidal labyrinth fin.

Experimental Investigation On Wear Behavior of Rectangular Labyrinth Fin Against High Speed Rotor

2021 ◽  
Author(s):  
Xin Yan ◽  
Xinbo Dai
Keyword(s):  
Friction Coefficient ◽  
High Speed ◽  
Wear Behavior ◽  
Early Stage ◽  
Labyrinth Seal ◽  
Contact Forces ◽  
Transient Temperature ◽  
Sliding Velocity ◽  
Material Loss ◽  
Temperature Distributions

Abstract The wear behaviors of a rectangular labyrinth seal fin against high speed rotor were experimentally investigated on the incursion test rig. The material losses, worn geometries, frictional temperature distributions, and contact forces of labyrinth fin in rubbing events were measured at three incursion rates, three final incursion depths and two rotor sliding velocities. The morphologies of the worn labyrinth fin tips were magnified to reveal the wear mechanisms in rubbing events. The transient temperatures and contact forces were detailed to analyze the thermal-mechanical interactions between two contacting parts. The results show that the material loss percentage in the labyrinth fin is higher at the early stage of rubbing process, accounting for 18% mass loss of the worn region, than at final stage. The material loss is decreased with increasing the incursion rate. The incursion rate and final incursion depth have pronounced effects on the mushroom region extensions and curlings. The friction coefficient is fluctuated significantly in the high sliding velocity and low incursion rate conditions, and the averaged value of friction coefficient is about 0.1-0.125 among all experiments. The temperature at labyrinth fin tip is increased with increasing the final incursion depth, incursion rate and sliding velocity. However, the temperature at fin tip is not increased further as it reaches about 1200°C. The heat convection from hot fin to ambient plays an important role in worn geometries and transient temperature distributions at fin tip.

Investigation on Wear Behavior at High Temperature of Smooth and Bionic Non-Smooth Samples

2012 ◽  
Vol 157-158 ◽  
pp. 1628-1631
Author(s):  
Xiao Dong Yang ◽  
Zhuo Juan Yang ◽  
You Quan Chen
Keyword(s):  
High Temperature ◽  
Wear Mechanism ◽  
High Speed ◽  
Room Temperature ◽  
Wear Behavior ◽  
High Speed Steel ◽  
Wear Test ◽  
Test Method ◽  
Wear Characteristics ◽  
Pin On Disk

By using pin-on-disk wear test method, the wear behavior of W9Gr4V high speed steel with smooth and non-smooth concave samples which treated by laser texturing technology was investigated between room temperature and 500 . It was found that the anti-wear ability of the non-smooth concave samples was increased more than that of the smooth ones and the anti-wear ability of the non-smooth samples was evident than the smooth ones at temperature increasing. In this paper, the anti-wear mechanism of non-smooth concave samples and wear characteristics with smooth and non-smooth samples in high-temperature were analyzed.

Wear Prediction of Strip Seals Through Conductance

2004 ◽  
Author(s):  
Farshad Ghasripoor ◽  
Norman A. Turnquist ◽  
Mark Kowalczyk ◽  
Bernard Couture
Keyword(s):  
Thermal Conductivity ◽  
High Speed ◽  
Wear Behavior ◽  
Close Correlation ◽  
Labyrinth Seal ◽  
The Body ◽  
Minor Effect ◽  
Labyrinth Seals ◽  
Steam Leakage ◽  
A Minor

Labyrinth seal assemblies are often used to reduce gas and/or steam leakage in turbines. Caulked-in continuous strip seals are one of the common forms of seals employed on both the rotating and stationary components of turbines. Labyrinth seals perform best when minimum clearances are achieved during the steady state operation of the turbine. However, the design of the turbine and its operation during transient periods of start-up, shut-down and hot re-start often result in interference between the seal components. In the case of the strip seals, this leads primarily to wear of the strip, which in effect adds to leakage. The aim of this paper is to show that strip tip heating and melting during the rub is the main mechanism of wear in the strip. Hence thermal conductivity through the strip and into the body mass in which it is caulked is the primary controlling factor in seal wear. This paper will discuss the use of thermal conductivity and geometry of the strip in predicting wear during high speed rubs against a proprietary material. A close correlation between calculated and experimental strip seal wear data with a number of seal alloys will be demonstrated. Test data will indicate that material properties such as tensile strength and hardness have a minor effect on the wear behavior of continuous seal elements during high-speed rubs.

Experimental Study on the Friction Contact Between a Labyrinth Seal Fin and a Honeycomb Stator

2015 ◽  
Vol 138 (6) ◽  
Author(s):  
Tim Pychynski ◽  
Corina Höfler ◽  
Hans-Jörg Bauer
Keyword(s):  
Experimental Study ◽  
Friction Velocity ◽  
Wear Behavior ◽  
Labyrinth Seal ◽  
Contact Forces ◽  
Metal Foil ◽  
Labyrinth Seals ◽  
Friction Temperature ◽  
Rubbing Behavior ◽  
Set Up

This paper presents results from an extensive experimental study on the rubbing behavior of labyrinth seal fins (SFs) and a honeycomb liner. The objective of the present work is to improve the understanding of the rub behavior of labyrinth seals by quantifying the effects and interactions of sliding speed, incursion rate, seal geometry, and SF rub position on the honeycomb liner. In order to reduce the complexity of the friction system studied, this work focuses on the contact between a single SF and a single metal foil. The metal foil is positioned in parallel to the SF to represent contact between the SF and the honeycomb double foil section. A special test rig was set up enabling the radial incursion of a metal foil into a rotating labyrinth SF at a defined incursion rate of up to 0.65 mm/s and friction velocities up to 165 m/s. Contact forces, friction temperatures, and wear were measured during or after the rub event. In total, 88 rub tests including several repetitions of each rub scenario have been conducted to obtain a solid data base. The results show that rub forces are mainly a function of the rub parameters incursion rate and friction velocity. Overall, the results demonstrate a strong interaction between contact forces, friction temperature, and wear behavior of the rub system. The presented tests confirm basic qualitative observations regarding blade rubbing provided in literature.

Wear Behavior and Mechanical Properties of TiO2 Coating Deposited Electrophoretically on 316 L Stainless Steel

2017 ◽  
Vol 140 (3) ◽  
Author(s):  
Hafedh Dhiflaoui ◽  
Khlifi Kaouther ◽  
Ahmed Ben Cheikh Larbi
Keyword(s):  
Mechanical Properties ◽  
Normal Force ◽  
Wear Behavior ◽  
Close Relation ◽  
Fretting Wear ◽  
Sliding Velocity ◽  
Wear Coefficient ◽  
Wear Performance ◽  
Characterization Methods ◽  
316 L Stainless Steel

In this work, the TiO2 coatings were synthesized by electrophoretic deposition (EPD) of nanosized powder in order to improve the tribological properties. Several characterization methods were applied to the coated substrates. The surface topography of the EPD layers, their morphology, composition, and mechanical properties were investigated. The influence of heat treatment, which results in calcination, on the wear performance of coated films was also examined. It was noticed that the effect of the normal force and sliding velocity on the coefficients of instantaneous and stabilized friction was not the same in treated coatings and untreated ones. Moreover, the treated and uncoated films showed a close relation between the dissipated accumulated energy and the worn volume. The energetic wear coefficients of fretting wear were also studied. As expected, the treated coating reduced the energetic wear coefficient, which enhanced the resistance to fretting wear.

Wear and Related Topology of Rubber Surface

2014 ◽  
Vol 42 (4) ◽  
pp. 200-215
Author(s):  
Paul Wagner ◽  
Frank Schmerwitz ◽  
Hagen Lind ◽  
Burkhard Wies
Keyword(s):  
Mass Loss ◽  
Wear Mechanism ◽  
Wear Behavior ◽  
Lateral Displacement ◽  
Wear Performance ◽  
Tire Industry ◽  
Image Velocimetry ◽  
Rubber Surface ◽  
Worn Surface ◽  
Measured Mass

ABSTRACT The wear mechanism of rubber is complex, and the direct experimental observations of wear are limited. The understanding of the wear mechanism and its prevention are important aims and fields of investigation in the tire industry. The most straightforward way to quantify wear is a measurement of the mass loss after wear experiments. The different mass loss of different rubber materials is used to classify the wear performance of the materials. An additional way to obtain information about the different wear behavior of different compounds and the mechanism is to take a look of the worn surface of the wheels. After wear experiments with real tires on the street or small rubber wheels in laboratory, microstructures normal to the slip direction occur, the so called Schallamach waves. The kinematic analysis of these structures can lead to a deeper understanding of the wear mechanism. The surfaces of four compounds with a different wear performance are investigated in this paper with the aim of distinguishing them not just through the measured mass losses but also through an analysis of the surface and the extraction of a characteristic. This characteristic is recognized as the lateral displacement of the surface structures. It is quantified using a new evaluation technique based on the particle image velocimetry (PIV) method. The lateral displacement is compound specific and is observed parallel to the lowering of the altitude due to mass loss. In addition, the observed microstructures are used to add a new aspect of local plasticization to the well-established wear mechanism theory.

Study of the Friction and Wear Behavior of Metal/Polymer-Metal Multi-Material Configurations

2017 ◽  
Vol 739 ◽  
pp. 211-219
Author(s):  
Viktor Krasmik ◽  
Josef Schlattmann
Keyword(s):  
Friction And Wear ◽  
Wear Behavior ◽  
Wear Performance ◽  
Friction And Wear Behavior ◽  
Test Setup ◽  
Wear Characteristics ◽  
Polymer Metal ◽  
Metal Polymer ◽  
Friction And Wear Characteristics

Using an adapted ball-on-pyramid test setup, the friction and wear characteristics of some exemplary multi-material configurations (metal/polymer-metal) are studied. The results reveal that a manipulation of the friction and wear performance by combining certain sample materials is possible.

Study on Electrical Sliding Wear Property of Cu/MoS2/Mo Composites

2011 ◽  
Vol 117-119 ◽  
pp. 913-916
Author(s):  
Dou Qin Ma ◽  
Jing Pei Xie ◽  
Ji Wen Li ◽  
Ai Qin Wang ◽  
Wen Yan Wang ◽  
...  
Keyword(s):  
Powder Metallurgy ◽  
High Speed ◽  
Sliding Wear ◽  
Adhesive Wear ◽  
Wear Behavior ◽  
Wear Test ◽  
Current Intensity ◽  
Wear Property ◽  
Sliding Velocity ◽  
Arc Erosion

In this paper, the Cu/MoS2/Mo composites were prepared by the powder metallurgy technology. The friction wear test was tested by the HST-100 High Speed Electric-tribometer. The microstructure and wearing surface morphology were examined by SEM and EDS. The electrical sliding wear behavior of the composites was discussed. The results indicated that the dense composites are obtained; the wear mechanisms of Cu/MoS2/Mo are mainly abrasive wear and adhesive wear with arc erosion; the effects of current intensity and sliding velocity on the wear property of the composites are complicated, and the composites show the best property when the current intensity is 60A and the sliding velocity is 40m/s.

Experimental Study on the Friction Contact Between a Labyrinth Seal Fin and a Honeycomb Stator

2015 ◽  
Author(s):  
Tim Pychynski ◽  
Corina Höfler ◽  
Hans-Jörg Bauer
Keyword(s):  
Experimental Study ◽  
Friction Velocity ◽  
Wear Behavior ◽  
Labyrinth Seal ◽  
Contact Forces ◽  
Metal Foil ◽  
Labyrinth Seals ◽  
Friction Temperature ◽  
Rubbing Behavior ◽  
Set Up

This paper presents results from an extensive experimental study on the rubbing behavior of labyrinth seal fins and a honeycomb liner. The objective of the present work is to improve the understanding of the rub behavior of labyrinth seals by quantifying the effects and interactions of sliding speed, incursion rate, seal geometry and seal fin rub position on the honeycomb liner. In order to reduce the complexity of the friction system studied, this work focuses on the contact between a single seal fin and a single metal foil. The metal foil is positioned in parallel to the seal fin to represent contact between the seal fin and the honeycomb double foil section. A special test rig was set up enabling the radial incursion of a metal foil into a rotating labyrinth seal fin at a defined incursion rate of up to 0.65 mm/s and friction velocities up to 165 m/s. Contact forces, friction temperatures and wear were measured during or after the rub event. In total, 88 rub tests including several repetitions of each rub scenario have been conducted to obtain a solid data base. The results show that rub forces are mainly a function of the rub parameters incursion rate and friction velocity. Overall, the results demonstrate a strong interaction between contact forces, friction temperature and wear behavior of the rub system. The presented tests confirm basic qualitative observations regarding blade rubbing provided in literature.

Modeling of Tread Block Contact Mechanics Using Linear Viscoelastic Theory3

2008 ◽  
Vol 36 (3) ◽  
pp. 211-226 ◽  
Author(s):  
F. Liu ◽  
M. P. F. Sutcliffe ◽  
W. R. Graham
Keyword(s):  
High Speed ◽  
Slip Rate ◽  
Material Model ◽  
Contact Forces ◽  
Block Modeling ◽  
Rate Dependent ◽  
Linear Viscoelastic Material ◽  
Linear Viscoelastic ◽  
The Impact ◽  
Good Agreement

Abstract In an effort to understand the dynamic hub forces on road vehicles, an advanced free-rolling tire-model is being developed in which the tread blocks and tire belt are modeled separately. This paper presents the interim results for the tread block modeling. The finite element code ABAQUS/Explicit is used to predict the contact forces on the tread blocks based on a linear viscoelastic material model. Special attention is paid to investigating the forces on the tread blocks during the impact and release motions. A pressure and slip-rate-dependent frictional law is applied in the analysis. A simplified numerical model is also proposed where the tread blocks are discretized into linear viscoelastic spring elements. The results from both models are validated via experiments in a high-speed rolling test rig and found to be in good agreement.

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