Validation and application of bearing and block tearing resistance; background to prEN1993-1-8:2021

This paper experimentally examined the impact of four different drying methods (free drying, press drying, vacuum drying and impingement drying) on paper physical properties including roughness, elongation, air permeance, tearing resistance, tensile index and bursting strength. The handsheets materials are HWBKP (Hardwood Bleached Chemical Pulp), SWBKP (Softwood Bleached Chemical Pulp), CTMP (Chemical Thermo mechanical Pulp) and ATMP (Advanced Thermo Mechanical Pulp). Good experimental data were obtained for the four pulps under different drying conditions. The results of our investigation indicate that press drying have lower surface roughness, elongation and air permeance but higher tearing resistance; the vacuum drying have higher roughness, tensile index and bursting strength; the impingement drying have lower tearing resistance, tensile index and bursting strength but higher elongation and air permeance. Selection of different drying conditions for effective productivity and quality improvement potential is proposed as a direction for the future dryer design.

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Evaluation of ductile tearing for API-5L X70 pipeline grade steel using SENT specimens

International Journal Sustainable Construction & Design ◽

10.21825/scad.v6i3.1129 ◽

2015 ◽

Vol 6 (3) ◽

pp. 8

Author(s):

Nicholas Ohms ◽

Diego Belato Rosado ◽

Wim De Waele

Keyword(s):

Crack Growth ◽

Crack Extension ◽

Crack Growth Resistance ◽

Fracture Surfaces ◽

Edge Notch ◽

Resistance Curves ◽

Unloading Compliance ◽

Inner Diameter ◽

Tearing Resistance ◽

Hardness Map

Pipelines in harsh environments may be subjected to large deformations. Classic stress-based design needs to be complemented with strain-based design. An important parameter in the design is the crack growth resistance. SENT testing (Single Edge Notch Tension) allows to determine the so-called material’s tearing resistance curve. Very recently the first standard on SENT testing, BS 8571:2014, has been published. SENT testing is however still subject to extensive research and different approaches with respect to eg. notch placement, crack extension measurement and analysis exist. In this paper two methods for calculating crack extension based on the unloading compliance procedure are used and compared, proving that they show little difference. This is performed on an API-5L X70 steel grade and this for different configurations, namely an inner diameter notch and a through thickness notch. The results showed little difference between the different configurations, although the inner diameter showed higher crack growth resistance. Furthermore, the results are compared to visual observations of the fracture surfaces and a hardness map. The fracture surfaces corresponded to the obtained resistance curves. However, no real correlation between the hardness map and the other results could be seen.

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Improving Tearing Resistance of Leather - Part 2 Prevention and Treatment of Low Tearing Strength in the Tannery

Journal of the American Leather Chemists Association ◽

10.34314/jalca.v117i1.4694 ◽

2022 ◽

Vol 117 (1) ◽

Author(s):

Ricardo Tournier ◽

Fernando Lado

Keyword(s):

Production Process ◽

Collagen Fibers ◽

Significant Source ◽

Tear Strength ◽

Prevention And Treatment ◽

World Class ◽

Tearing Resistance ◽

Over 40 Years ◽

Tearing Strength ◽

Production Part

An appropriate tear strength is one of the main properties that concern customers and it is also a significant source of claims. The authors make a review of the production process, focusing on each step that can either damage the natural strength of collagen fibers or improve them, and therefore, the leather. The aim of this work, divided in Part 1 and 2, is to transfer field tannery experiences collected over 40 years of activity in different tanneries, to colleagues that are looking for world class leather production. Part 1 has been published in JALCA, 116 (12), 2021.

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Tearing Resistance of Advanced Double Hulls

Journal of Ship Research ◽

10.5957/jsr.1997.41.1.69 ◽

1997 ◽

Vol 41 (01) ◽

pp. 69-80

Author(s):

Mark D. Bracco ◽

Tomasz Wierzbicki

Keyword(s):

Steady State ◽

Cutting Force ◽

Average Error ◽

Small Scale ◽

Complex Deformation ◽

Scale Models ◽

State Force ◽

Deformation Patterns ◽

Double Hull ◽

Tearing Resistance

This paper studies the cutting by a wedge of advanced double hull (ADH) small-scale models. A total of six cutting experiments were performed with six different wedge geometries. Complex deformation patterns observed in the damaged specimens were simplified to obtain a closed-form upper bound for the steady-state cutting force. The ADH steady-state cutting force solution varied from 6% above to 12% below the experimental mean steady-state force. The absolute average error is 5%.

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