Wear monitoring method of polymer thrust bearing based on ultrasonic reflection coefficient amplitude spectrum (URCAS)

Patent metadata

Field	Value
Publication number	US-12158447-B2
Application number	US-202318371582-A
Country	US
Kind code	B2
Filing date	Sep 22, 2023
Priority date	Sep 23, 2022
Publication date	Dec 3, 2024
Grant date	Dec 3, 2024

Abstract

A wear monitoring method of a polymer thrust bearing based on an ultrasonic reflection coefficient amplitude spectrum (URCAS), includes: selecting a corresponding delay block probe based on a material of a to-be-tested bearing, and setting corresponding parameters of a pulse generator; after collecting a primary echo from a surface of the delay block probe as a reference signal, placing the delay block probe in a designated region on a back of the to-be-tested bearing, and collecting time-domain echo signals from upper and lower surfaces of the bearing; establishing a propagation model of an ultrasonic signal in a polymer bearing, and calculating a theoretical URCAS based on the propagation model; calculating a measured URCAS; and constructing an objective function, and solving the objective function by using a differential evolution algorithm. A plurality of parameters of the polymer bearing is solved to meet a requirement for wear monitoring by adopting the method.

First claim

What is claimed is:

1. A wear monitoring method of a polymer thrust bearing based on an ultrasonic reflection coefficient amplitude spectrum (URCAS), comprising following steps:
selecting a corresponding delay block probe based on a material of a to-be-tested bearing, setting corresponding parameters of a pulse generator, connecting the delay block probe to the pulse generator, and connecting the pulse generator to a digital oscilloscope;
after collecting a primary echo from a surface of the delay block probe as a reference signal, placing the delay block probe in a designated region on a back of the to-be-tested bearing, and collecting time-domain echo signals from upper and lower surfaces of the bearing;
establishing a propagation model of an ultrasonic signal in a polymer bearing, and calculating a theoretical URCAS based on the propagation model;
calculating a measured URCAS based on the time-domain echo signals collected from the upper and lower surfaces of the bearing; and
constructing an objective function based on the measured URCAS and the theoretical URCAS to represent a similarity between measured echo data and theoretical calculated echo data, and solving the objective function by using a differential evolution algorithm, wherein when a correlation coefficient is largest and a root-mean-square error is smallest, a similarity between the measured URCAS and the theoretical URCAS is largest, and in this case, independent variables corresponding to the objective function are parameters of the polymer bearing; wherein
during calculation of the theoretical URCAS, a reflection coefficient R of a polymer layer is expressed as follows:

R
=

P
1

+

P
2

P
1

=

r

1
⁢
2

+

t

1
⁢
2

⁢

r

2
⁢
3

⁢

t

2
⁢
1

⁢

exp
⁢

(

-
2

⁢
α
⁢
d

)

⁢

cos
⁢

(

4
⁢
π
⁢
fd

c
2

)

r

1
⁢
2

+

i
⁢

t

1
⁢
2

⁢

r

2
⁢
3

⁢

t

2
⁢
1

⁢

exp
⁢

(

-
2

⁢
α
⁢
d

)

⁢

sin
⁢

(

4
⁢
π
⁢
fd

c
2

)

r

1
⁢
2

the reflection coefficient R of the polymer layer is a complex number, a modulus of the reflection coefficient is a function of a frequency, and the function is referred to as the URCAS, which is expressed as follows:

R
⁡
(
f
)

=

{

[

r

1
⁢

Assignees

• Univ Wuhan Tech

Inventors

• Yan Xinping
• Ning Changxiong
• Ouyang Wu
• Hu Fei

Classifications

• G01M13/04

  Bearings · CPC title

• F16C2233/00

  Monitoring condition, e.g. temperature, load, vibration · CPC title

• F16C41/00

  Other accessories, {e.g. devices integrated in the bearing not relating to the bearing function as such} · CPC title

• F16C33/20

  Sliding surface consisting mainly of plastics (F16C33/22 - F16C33/28 take precedence) · CPC title

• F16C17/04

  for axial load only · CPC title