Sensing Roll Pressure Mapping for Continuous Nip Uniformity Monitoring

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Solution Overview

Problem

Conventional methods for measuring nip pressure uniformity in nip presses are limited, as they require the press to be stopped and cannot account for temperature and roll speed changes, leading to potential paper quality issues due to uneven pressure distribution.

Innovation Solution

A system with multiple sensors on a sensing roll and a mating roll that collects data on rotational variability, generating a synchronized map of pressure profiles to detect roll or bearing changes and adjust pressure distribution in real-time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional nip pressure measurement methods are used (stopping the press to take impressions), then measurement simplicity is maintained, but production continuity is lost and temperature/roll speed changes cannot be accounted for

Engineering Contradiction:
Improveproduction continuityVSAvoidmeasurement system complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent replaces conventional mechanical impression-taking methods with electronic pressure sensors that continuously measure nip pressure during operation. Sensors are mounted on the roll surface to detect pressure variations without requiring the press to stop, thereby maintaining production continuity while providing real-time data for analysis.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The measurement system enables continuous pressure monitoring during press operation rather than intermittent measurements. The sensors continuously capture pressure data as the roll rotates, allowing for real-time detection of pressure uniformity issues without interrupting the papermaking process.

Inventive Principle:
Principle #20Continuity of useful action

2Measurement precision

If multiple sensors are deployed on the sensing roll to map rotational variability, then pressure measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improvepressure measurement precisionVSAvoidsensor system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The sensing roll surface is divided into multiple discrete sensor locations arranged in axial and circumferential patterns. Each sensor measures pressure at its specific location, and the combined data creates a detailed map of pressure distribution across the roll surface, improving measurement precision through spatial segmentation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from single-point pressure measurement to two-dimensional pressure mapping by deploying sensors in both axial and circumferential directions on the roll surface. This dimensional expansion allows comprehensive characterization of pressure uniformity and rotational variability.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Manufacturing precision

If real-time pressure monitoring is implemented, then paper quality control is improved, but data processing complexity increases

Engineering Contradiction:
Improvepaper quality uniformityVSAvoiddata processing complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The system continuously monitors nip pressure in real-time and provides feedback on pressure uniformity and rotational variability. This feedback mechanism enables operators to detect and correct pressure distribution issues that affect paper quality, maintaining consistent product standards through ongoing measurement and analysis.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent creates a digital replica or map of the physical pressure distribution on the roll surface by collecting data from multiple sensors. This pressure profile map serves as a simplified representation of the complex three-dimensional pressure field, making the data more manageable for analysis and interpretation.

Inventive Principle:
Principle #26Copying

Data Source

PatentEP3351681B1Method and system associated with a sensing roll including pluralities of sensors and a mating roll for collecting roll data
Publication Date: 2024.11.20 INT PAPER CO
  • EP3351681B1 patent drawingFigure 1
  • EP3351681B1 patent drawingFigure 2
  • EP3351681B1 patent drawingFigure 3A~3C

AI summary

Collecting roll data associated with a sensing and mating rolls that form a nip uses first and second pluralities of sensors. Each sensor of the first plurality has a corresponding sensor in the second plurality which is associated with a same respective axial location on the sensing roll but is spaced-apart circumferentially. The sensors are located at axially spaced-apart locations of the sensing roll and generate either a first or second respective signal when entering the nip. Upon receiving a generated signal, a determination is made about which sensor generated the received signal and the membership of that sensor in one of the pluralities. Based upon a rotational position of the mating roll, a determination is made of which tracking segment associated with the mating roll enters the region of the nip concurrently with the signal to store the signal using the determined one tracking segment and the determined membership.