Zawada NDT



The Instrument Set for Non-destructive Magnetic Testing of Wire Ropes

MD120 photo  Meraster S.A. instrument for NDT wire rope inspection examination non-destructive testing of wire ropesSince 1979, Meraster has supplied instruments to estimate the in-situ deterioration of wire ropes around the world.

 The operation of our NDT instruments is based on permanent magnet method, which was developed in Poland and is used throughout the world. Meraster's standard range of sensing measuring heads can be used for ropes ranging from 8 to 90 mm diameter. Custom designed heads are also available. For smaller ropes our MD-20 hand-held head-tester can be used.

 Recently developed by Meraster, the MD120 recording system includes a specially designed portable chart recorder with additional data recording which can be transferred to a computer. This unique instrument has been designed as a helpful and comfortable tool, to meet the special needs of rope experts in industrial environments.

 Unique features: MD 120 Wire Rope Defectograph

MD120 Defectograph uses today's knowledge and technology to provide the maximum possible information that can be obtained from a rope in situ under non-destructive testing.


MD120 and GP photo  Meraster S.A. instruments for NDT wire rope inspection examination non-destructive testing of wire ropes

Rope size range
GP series standard heads diameter  from 8 to 85 mm 
heads GP-1 type from 30 to 85 mm
heads GP-2 type from 20 to 60 mm
heads GP-3 type from 10 to 30 mm
head GP-4  from 10 to 26 mm
head GP-5  from 10 to 15 mm
heads GP-6 type from 8 to 14 mm
Hand-held testerMD-20 as a head from 8 to 22 mm
GM series light-weight heads from 10 to 90 mm 

Rope types
wire ropes made of ferromagnetic steel, any form of construction

 Detected rope defects

Able to detect
all important defects to estimate rope deterioration; maximum sensitivity may be as high as 0.05% of nominal rope metallic cross-sectional area (but such defect readability depends on the rope's construction)

 Defect positioning on rope length
with rope length converter RI, mounted in heads GP-1 type, GP-2 type, GP-3 type, GM or separate for others

Defect positioning of depth inside rope
with heads equipped with double inductive sensors ("inner" and "outer"), i.e. heads GP-1 type, GP-2 type, GM

 Operating conditions
Temperature from -25° to + 40° C 
for recording on paper from 0° to + 40° C 
Relative humidity to 95% 
for recording on paper from 25 to 85%

Dimensions and weight of measuring heads
See: "GP Measuring Heads", "GM Measuring Heads", "MD-20 Wire Rope Tester"


MD 120 Wire Rope Defectograph

Application range
This instrument is intended to record signals from magnetic sensing heads for testing wire ropes. It may also be direct applied to recording other electric signals within its sensitivity range 1mV/mm to 3.2 V/full scale or it may be customised to record within another required range, from 50 µV/mm.

 Main modes

Recording channels

Wire rope test chart

printed chart example, Meraster NDT, wire rope inspection, examination in-service

Recording method
Thermal array line printing head, printing on thermal paper on a roll 112 mm x 25m

Rope speed range at compensation of speed influence to inductive sensor signals
0.05 to 10 m/s

Displayed rope speed range
0.05 to 9.99 m/s by 0.01m/s, over range indicated

 Rope length display range 1 to 9999 m by 1 m reversible, up/down counting option, initial length setting capability

 Length converter input
2 x 100 pulses/m (type RI)

 Paper chart drive
1, 2, 5, 10 mm/m of rope or 1, 2, 5, 10 mm/second at synchro-feed rope speed should be limited
at 1 mm/m to 7.0m/s
at 2 mm/m to 7.0m/s
at 5 mm/m to 3.6m/s
at 10 mm/m to 1.8m/s
"Zoom replay" ratio 20 mm/m of rope or mm/s

"Zoom replay" memory capacity 18.75 m of rope or 18.75 seconds of recording

 Acoustic signal of rope defect level
10, 20, 90% of full scale of the inner sensor channel (beeper and also headphones)

 "Settings & Rope Code" Memory
Capacity 100 items


Diagram memory (optional Memory Card)
Type: SRAM Memory Card pc-card2m.jpg - 19681 Bytes
PCMCIA type I or II, 
Capacity:  512 kB to 4 MB, i.e.
300 to 2400 m of rope at synchro mode
or 300 to 2400 seconds (40 min) of recording
Recorded data: 3 signal channels + integral channel
at sampling rate 2.5 mm or ms
recorder settings, rope code, time, date
rope length counter
Data replaying: printing selected sectors with MD120 
with computer and software tools 

Required interface for data transfer from diagram memory to the computerPCMCIA port & professional, byte level software driver

 Sensitivity range
Outer and inner coil channels

Hall-effect sensor channel Integral of inductive signal Power Dimensions
47.5 x 37 x 17.5 cm

with standard accessories 13 kg Fax: +48 32 376 7900 Phone: +48 32 271 6231
Mail: Zawada NDT, ul. Tatarkiewicza 8, PL- 41-819 Zabrze, POLAND
Office/Visit: Zawada NDT, ul. Roosevelta 120 bud. B-5 (GPS: Roosevelta 118), 41-800 Zabrze, Poland