Evident LogoOlympus Logo
자료실
Application Notes
자료로 돌아가기

TOFD 병렬 스캔


Automatic Fastener Hole inspection in Aircraft

Overview

Most typical TOFD inspections are performed with the send and receive transducers on opposite sides of the weld and scanning movement parallel to the weld axis. The main purpose of this “perpendicular” (defined by beam to weld relationship) scanning is to quickly perform weld inspection with the weld cap or re-enforcement in place. This technique can give location in the scan axis, the indication length, height of indication and flaw characterization information. One of the weaknesses of this technique is the lack of index positioning (or where between the probes) the indication is located. This information is usually obtained with complimentary pulse echo ultrasonics when the weld is left in place. Parallel TOFD scanning, where the scan direction and beam direction are the same is less used, for obvious reasons of not being able to cover the entire length of weld rapidly, more complex movement pattern required of scanner mechanisms, and complexity of the data output of an entire weld inspected. This technique does have advantages when it is possible to be performed.

Typical “Perpendicular” Weld Scanning Setup and Data Collected. Data is side view of weld from scan start to scan finish down the weld. Position of encoder and scanning direction are highlighted.Typical “Perpendicular” Weld Scanning Setup and Data Collected. Data is side view of weld from scan start to scan finish down the weld. Position of encoder and scanning direction are highlighted.

Typical “Perpendicular” Weld Scanning Setup and Data Collected. Data is side view of weld from scan start to scan finish down the weld. Position of encoder and scanning direction are highlighted.

Typical “Parallel” Weld Scanning Setup and Data Collected. Data is side view of weld from scan start to scan finish across the weld. Position of encoder and scanning direction are highlighted.Typical “Parallel” Weld Scanning Setup and Data Collected. Data is side view of weld from scan start to scan finish across the weld. Position of encoder and scanning direction are highlighted.

Typical “Parallel” Weld Scanning Setup and Data Collected. Data is side view of weld from scan start to scan finish across the weld. Position of encoder and scanning direction are highlighted.

Benefit of TOFD Parallel Scanning

Although perpendicular TOFD scanning down the weld can give highly accurate depth measurement, generally speaking a parallel scan will give more accurate depth information as well as flaw information, and location in the index position in the weld. With perpendicular scanning, no index position is possible without multiple offset scans being performed or complimentary NDT techniques to position the flaw. In parallel scanning Index position is ascertained by locating the minimum time peak, which corresponds to when the indication is centered between the two probes. For these reasons this technique is often used in critical crack sizing inspections, as well as change monitoring, in other words, monitoring a crack or other defect for growth until it reaches a critical level at which time it is repaired or replaced. For these reasons the technique is often performed on critical components that are costly to shut down for repair, often in the Power Generation industry. More information is often gathered from the flaw as diffraction occurs across the flaw instead of just down the flaw.

Equipment Used

OmniScan SX or MX2

  • Instrument options vary, OmniSX-UT (U8779743) minimum recommended platform

TOFD Probes and Wedges

  • Centrascan Piezocomposite Transducers- Frequency and Size vary by application
  • ST1/ST2 TOFD Wedges-Rexolite and Stainless Steel Options

Industrial Scanner and Accessories

Optional Software and Accessories

  • OmniPC and NDT Setup Builder (U8775269) or TomoView (U8148031) post analysis software

* Application note created with samples provided by University of Ultrasound

Olympus IMS

이 애플리케이션에 사용되는 제품
OmniScan ™ X3 시리즈의 모든 결함 탐상기는 완전한 위상 배열 툴박스입니다. 혁신적인 TFM 및 고급 PA 기능은 강력한 소프트웨어 도구와 간단한 워크 플로우로 생산성을 향상시키는 동시에 결함을 확실하게 식별하는 데 도움이됩니다.
비행 시간 회절(TOFD) 탐촉자와 쐐기는 강철에서 굴절된 종파를 발생시키며, 일반적으로 균열의 크기를 결정하는 데 사용됩니다. 탐촉자는 감쇠도가 높아 까다로운 응용 분야에서 우수한 해상도를 제공합니다. 민감성 복합 요소를 가지고 있으며, 2.25MHz에서 15MHz까지의 주파수 및 3mm(0.25인치)에서 12 mm(0.5인치) 크기로 제공됩니다.
OmniScan™ MX2 2채널 기존 초음파 모듈(UT2)은 회절파 시간 측정(TOFD) 검사에 사용할 수 있습니다.이 제품은 높은 펄스 발생 전압(340V), 향상된 PRF 성능 및 개선된 신호 대 잡음비(SNR)가 특징입니다.
단일 그룹인 경량 옴니스캔 SX는 읽기 쉬운 8.4인치(21.3cm) 터치 스크린을 갖추고 있으며, 비용 효율적인 솔루션을 제공합니다. 옴니스캔 SX는 SX PA와 SX UT의 두 가지 모델로 제공됩니다. SX PA는 UT 전용 SX UT와 마찬가지로 P/E, P-C 또는 TOFD 검사를 위한 재래식 UT 채널을 장착한 16:64PR 장치입니다.
옴니스캔 MX2는 이제 UT 채널이 있는 새로운 위상 배열 모듈(PA2), TOFD(회절 비행 시간)에 사용할 수 있는 새로운 2채널 재래식 초음파 모듈(UT2) 및 성공적인 옴니스캔 MX2 플랫폼의 기능을 확장하는 새로운 소프트웨어 프로그램을 제공합니다.
죄송합니다. 이 페이지는 해당 국가에서 사용할 수 없습니다.
아래 양식을 작성하여 원하는 내용을 알려주십시오.
죄송합니다. 이 페이지는 해당 국가에서 사용할 수 없습니다.