Kiwa CMT Testing. CMT (Testing) Ltd. Established in 1976 Located in Derby with 27 employees

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1 CMT (Testing) Ltd Established in 1976 Located in Derby with 27 employees *UKAS Accredited *ASLEC Registered *CHAS Accreditation *Constructionline *ILE & BSI Members

2 UKAS United Kingdom Accreditation Service CMT are accredited for RLS testing of steel lighting columns

3 What do CMT do? Four Departments Structures Soils & Site Investigation Chemistry Concrete & Building Products

4 COLUMN TESTING RELATIVE LOSS OF SECTION (RLS) Instrument for assessing the loss of steel at the four most vulnerable positions of a steel lighting column

5 RLS LOSS OF SECTION MONITORING Can identify corrosion up to 100mm below ground without excavation Minimal surface preparation Can detect narrow-band full penetration Mini head can pinpoint position of greatest loss Average loss of section in scanned area is measured Both heads can be used elsewhere on the columns

6 Critical Zones Swaged Joint Bottom of the door opening Below the door opening Below ground. At the root

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8 Structures Department Lighting Column Testing RLS & SJA Test Equipment Only UK company UKAS Accredited for Structural Testing of Lighting Columns. Complies with TR22

9 TEST WHERE IT MATTERS Corrosion occurs around and below ground level due to: *dog urine *de-icing salts *weed killers *strimmers etc This coincides with the maximum bending moment

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13 The Solution Kiwa CMT Testing

14 How does the instrument work? The RLS works on low frequency magnetic flux. It s a dry coupled system that looks below GL for loss of steel section compared to a reference reading that is taken within an area that is considered to be of sound material (back of door on base of column)

15 PULSED EDDY CURRENT TECHNIQUE - Reference Column walls SENSOR HEAD EDDY CURRENT REGION PULSED MAGNETIC FIELD Pulses of shaped magnetic field are induced into the column and travel downwards to emerge 100mm below and return into the base of the search head. Each pulse induces eddy currents within the column wall and surfaces. The eddy currents are detected and the signal logged. Repeat the test elsewhere on the pole and the signals are compared and the difference computed.

16 PULSED EDDY CURRENT TECHNIQUE Test area Column walls SENSOR HEAD EDDY CURRENT REGION PULSED MAGNETIC FIELD Pulses of shaped magnetic field are induced into the column and enter the root and travel upwards to emerge above ground and back into the search head. Each pulse induces eddy currents within the column wall and surfaces. The eddy currents are detected and processed to indicate the difference in section between the two test areas.

17 RLS testing using the standard head Penetrates 10mm wall thickness (or greater) Penetrates ground to a depth of 100mm Assesses loss from both inner and outer surface Compares areas of the same section of column Ground level P1 P2 P4 P3 Sensed zone 200 x 200mm Four equally spaced measurements around columns and averaged to classify

18 The instrument will look through surface coatings and only measures sound steel *Painted Surfaces *Galvanising *Metal Spray Kiwa CMT Testing *Bituminous material

19 The column could be planted in: * Asphalt * Coated macadam * Concrete / paving slabs * Soil * Clays etc The instrument WILL penetrate these materials.

20 Typical Tubular Steel Lighting Column Kiwa CMT Testing

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22 RLS testing using the Mini head Penetrates 10mm wall thickness or greater Pinpoints position of greatest loss Door aperture The Mini head is to be used on folded columns or columns that are 125mm diameter or less Ground level Asphalt Coated macadam Concrete Soil Sensed zone 65mm wide 50mm deep

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24 Folded Column Kiwa CMT Testing

25 P3 Kiwa CMT Testing FOLDED COLUMNS P2 P4 300mm D o o r Door P1 Lap / P3 Taper G.L.

26 Possible source of anomalies Cable aperture within sensed zone Interference from adjacent steel Foreign metallic objects beneath search head Poor reference reading Deformation at the root due to impact Scabbing increasing standoff distance Manufacturing variation Difference in column section

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28 Ornate Column Stainless Steel Column

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31 Swage Joint Analyser This instrument can be used for other areas on a column as well as the Hot Swaged Joint connection. e.g. Just above flange plated columns to detect internal corrosion

32 Minimal surface preparation Unaffected by surface coating Detects loss from inner surface of swaged joint Possible to monitor changes in column and joint condition with time Can be used to compare thickness of 10 x 10mm areas elsewhere on the column Can be used on the inside of a column to any depth using probe

33 Diagram of swage Kiwa CMT Testing

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35 Internal corrosion using probe

36 Flange Plated Column, Internal Corrosion Identified Using SJA

37 Weighting details Weightings of -4 and -8 are added to the average value if any of the 4 reading fall into class 3 and class 4/5 respectively. 0 Kiwa CMT Testing =-32/4= -8 (Class 1) Due to the -32 value we add a weighting of -8 to the average value therefore overall becomes -16 (class 2)

38 Typical section of RLS report

39 Interpretation & Recommendations TR22 Category CMT Class Average LSU s Recommendation 2U 5 >-50 Immediate removal or making safe the unit 1U 4-25 to -50 Schedule for Removal/Replacement as soon as practicable or in accordance with Operating Authorities Action Matrix 2G 3-17 to -24 Re-test within 2 years 3G 2-11 to -16 Re-test within 3 years 6G 1 0 to -10 Re-test within 6 years

40 LSU s v % Loss of Section

41 RLS 1-D Mk2 Examples of estimated loss of section in the zone 200mm wide from GL to -100mm Surface pitting no necking Hole present surface pitting Elongated hole some necking Large hole significant necking

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43 Conclusion No surface preparation therefore no lasting defects/marks on the column Can identify and quantify corrosion below GL without excavation Identifies internal & external corrosion Concentrates on areas identified as high risk that could lead to catrostrophic failure UKAS accredited Identified as a recognisable test in TR22 Reporting giving recommendations on each column tested Hand held instrumentation therefore no need for expensive traffic management

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