Methods of making a tubular specimen with a predetermined wrinkle defect

Patent metadata

Field	Value
Publication number	US-11566984-B2
Application number	US-202016923413-A
Country	US
Kind code	B2
Filing date	Jul 8, 2020
Priority date	Mar 21, 2017
Publication date	Jan 31, 2023
Grant date	Jan 31, 2023

Abstract

A method of offset load testing a tubular composite specimen with two pairs of aligned holes and having at least one defect, the method comprising: providing a testing apparatus having a pair of arms including a fixed arm and a mobile arm; securing the pair of arms using a fastener assembly in each of the two pairs of aligned holes; and moving the mobile arm to impart an offset load force to the tubular specimen. One aspect includes a method of offset load testing comprising: providing a testing apparatus having a pair of arms including a fixed arm and a mobile arm; providing a tubular composite specimen with a top portion and a bottom portion; securing the pair of arms to the top and bottom portions of the tubular composite specimen; and moving the mobile arm to impart an offset load force to the tubular composite specimen.

First claim

What is claimed is:

1. A method of offset load testing a tubular composite specimen having at least one wrinkle defect, the method comprising:
providing a testing apparatus having a pair of arms including a fixed arm and a mobile arm, each of the fixed arm and the mobile arm including a fastener assembly;
providing the tubular composite specimen with a top portion with a first pair of aligned holes, a bottom portion with a second pair of aligned holes, and a center portion disposed between the top portion and the bottom portion, the top and bottom portions each include a plurality of reinforcement layers comprising fiberglass plies, the center portion including at least one wrinkle defect;
securing the pair of arms using the respective fastener assembly in each of the first and second pair of aligned holes in the tubular composite specimen; and
moving the mobile arm to impart an offset force to the center portion of the tubular composite specimen;
wherein the plurality of reinforcement layers prevent the tubular composite specimen from bending in the top and bottom portions during the moving step.

2. The method according to claim 1 , wherein the testing apparatus is at least one of the following: a tensile testing machine, a compressive testing machine, and a tension-torsion testing machine.

3. The method according to claim 1 , wherein the at least one wrinkle defect comprises an out of plane distortion of an element of a composite fiber.

4. The method according to claim 1 , wherein the method further comprises:
generating at least one wrinkle defect in the tubular specimen with a predetermined characteristic.

5. The method according to claim 1 , wherein the fastener assembly in the securing step is oriented about 90 degrees from a longitudinal axis of the mobile arm.

6. The method according to claim 1 , wherein the fastener assembly comprises a round rod disposed in the respective first or second pair of aligned holes and a securing fastener for securing the round rod in the respective first or second pair of aligned holes.

7. The method according to claim 1 , wherein the moving of the mobile arm bends the center portion of the tubular composite specimen.

Assignees

• Bell Textron Inc
• Textron Innovations Inc

Inventors

• Lee Wei-Yueh
• Burnett Michael
• Dearman Michael

Classifications

• B29C70/30

  Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core · CPC title

• G01N2203/0096

  Fibre-matrix interaction in composites · CPC title

• G01N2203/0274

  Tubular or ring-shaped specimens · CPC title

• G01N3/04

  Chucks · CPC title

• B29L2023/22

  Tubes or pipes, i.e. rigid (bent tubes not for use as pipe couplings B29L2023/004) · CPC title