Creping Blade Trailing Edge Radius for Web Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current creping blades in papermaking processes often cause issues such as reduced throughput, web tearing, strength loss, and dust generation due to their sharp trailing edges, which increase friction and drag forces on the web.

Innovation Solution

The creping blades feature a non-planar trailing edge with a radius of greater than 0.001 inches, providing a blunt geometry that reduces friction and drag, improving machine performance and product attributes like sheet stability and line speed.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a sharp trailing edge is used on the creping blade, then the blade can effectively remove the web from the drying drum, but it causes increased friction and drag forces on the web leading to web tearing and strength loss

Engineering Contradiction:

Improveweb removal effectivenessVSAvoidweb strength

Core Design Contradiction:

ProductivityVSStrength

Solution Approach 1:

The trailing edge of the creping blade is modified from a sharp edge to a curved surface with a radius of curvature between 0.002 inches and 0.020 inches. This curvature reduces the concentration of stress and friction at the trailing edge, thereby reducing drag forces on the web and preventing web tearing while maintaining effective web removal capability

Inventive Principle:

Principle #14Spheroidality (Curvature)

2Productivity

If a sharp trailing edge is used on the creping blade, then the blade can remove the web efficiently, but it generates excessive dust from the web material

Engineering Contradiction:

Improveweb removal efficiencyVSAvoiddust generation

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The curved trailing edge surface distributes the contact area between the blade and web, reducing localized friction and material disruption. This results in significantly reduced dust generation from the web material while maintaining efficient web removal from the drying drum

Inventive Principle:

Principle #14Spheroidality (Curvature)

3Productivity

If a sharp trailing edge is used on the creping blade, then the blade can strip the web from the drum, but it reduces line speed and throughput

Engineering Contradiction:

Improveweb stripping capabilityVSAvoidline speed

Core Design Contradiction:

ProductivityVSSpeed

Solution Approach 1:

The curved trailing edge reduces frictional resistance between the blade and web during the creping process. This reduction in drag forces allows for increased line speeds and improved throughput while maintaining effective web stripping capability from the drying drum surface

Inventive Principle:

Principle #14Spheroidality (Curvature)

4Productivity

If a sharp trailing edge is used on the creping blade, then the blade can separate the web from equipment, but it creates a traumatic interaction that reduces web stability

Engineering Contradiction:

Improveweb separation effectivenessVSAvoidweb stability

Core Design Contradiction:

ProductivityVSStability of the object's composition

Solution Approach 1:

The curved trailing edge provides a gradual separation interface between the blade and web, reducing sudden stress concentrations and traumatic interactions. This improves web stability during the creping process while maintaining effective separation from the drying drum or other equipment

Inventive Principle:

Principle #14Spheroidality (Curvature)

Data Source

PatentUS7431801B2Creping blade

Publication Date: 2008.10.07 PROCTER & GAMBLE CO

AI summary

A creping blade including a body having a leading side, a trailing side, and working end including a bevel surface. The bevel surface is defined by a leading edge and a trailing edge, wherein the trailing edge of the creping blade has a trailing edge radius of greater than about 0.001 inches (about 0.0254 mm).