Software in non-destructive testing of wire ropes

Zawada NDT
WIRE ROPE INSPECTION

Z-NDT software in non-destructive testing of wire ropes

1. Introduction

Non-destructive testing of wire ropes has been performed commonly with recording on the paper strip chart. Meraster MD120 Defectograph has additionally a removable solid state memory as an option. This is a credit card size S-RAM IC Memory Card conforming PCMCIA (PC Card) standard.

PCMCIA cards are compatible with notebook computers. Also PCMCIA slots can be added to most of personal computer systems. In certain rope NDT conditions (subject to magnetism and dirt) and to improve operating conditions, this method of data transfer has many advantages. For example: PCMCIA Memory Cards feature ruggedness, magnetic field proof principle of operation and fast interfacing.

With this option, the Defectograph may store additionally an all-rope test record in the memory card. Capacity of the recording depends on the card version, e.g. 4 MByte card can storage test of a rope of 2400 m. Then data may be sent easily and quickly to a computer via the PCMCIA slot. This way, the user can archive many test records for further comparative analysis and can employ graphical, scientific software to help him in his work on rope test results. Also data from Memory Card may be replayed on a strip chart with an MD120 Defectograph, including old test records from computer storage memory.

Fig.1. Signal runs on Defectograph strip chart

2. Software browser MD120 PRE+

The Browser program is a rope test viewer allowing visualisation of measurements results recorded by the MD 120 Defectograph and copied by MCE program. Built-in functions allow:

Sensing heads' signal visualisation
Recorded runs printing
Basic statistical analysis and statistical report generation
Export of results as data in text format, witch can be used further by other programs e. g. MS EXCEL
Graphs transfer by the clipboard, allowing attachment to another documents

The program requires a PC-compatible computer with the MS Windows 9x/NT/XP operating system installed. Browser has a number usable options. Only some specific features are discussed below.

Panel windows can contain not only graphs, but also additional descriptive text information. These description texts can be assigned to any point of graph. These additional descriptive data and the text entered are stored in separate disk file with the main file name the same as the corresponding measuring data file name

Users have wide range of possibilities to change current tested rope segment and appropriate measurement data visualised. You can display all contents of the current measurement file or only a part of this data.

Fig.2. Signal runs of rope test shown by MD120 PRE+ program

Fig.3. Selected section of rope test shown by MD120 PRE+ program

The Export command allows export of measurement data to save in a text file (using text data format). Following measurement data records are saved using data format witch can be recognised by spreadsheets and by data base management systems, databases (data fields are separated by a comma [,]). Example contents of this type file shown below.

Fig.4 Export text file

Command Report performs statistical analysis of current graph displayed and records results using disk file. During the analysis all ranges exceeding limiting levels are detected and located for each channel. For each exceeding range - range length and point of max. exceeding location are calculated. Results received for each channel are joined together to prepare summary analysis by groups. The analysis results are recorded into new text file created.

Fig.5 Report text file

Report file may be edited and included into rope test report document. After simple edition this data can be also used as a data file to import by spreadsheet programs. When calibration dependences has been also included into spreadsheet, using spreadsheet formulas rope expert is able to automatically calculating rope defects more effectively.