HDG INSPECTION, SAMPLING & STORAGE ALANA HOCHSTEIN CORROSION ENGINEER, AMERICAN GALVANIZERS ASSOCIATION AMEGAC GALVAFORUM 2018, MARCH 8, QUERÉTARO

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1 HDG INSPECTION, SAMPLING & STORAGE ALANA HOCHSTEIN CORROSION ENGINEER, AMERICAN GALVANIZERS ASSOCIATION AMEGAC GALVAFORUM 2018, MARCH 8, QUERÉTARO

2 INSPECTION Galvanizer s responsibility ASTM A123 requirements for inspection Sampling process to inspect for coating thickness Storage best practices Wet storage stain Prevention Cleaning

3 HDG INSPECTION (INSPECCIÓN DE GALVANIZADO)

4 GALVANIZER S RESPONSIBILITY (RESPONSABILIDAD DEL GALVANIZADOR) Perform inspection at plant Ensure compliance to ASTM A123 Repair or regalvanize until material meets inspection requirements Maximum repair size found in the galvanizing specifications A123, A153, or A767 Prevent heavy wet storage stain at the plant Special Instructions Should be stated on Purchase Order Agreement

5 A123 INSPECTION REQUIREMENTS (INSPECCIÓN POR A123) Minimum Coating Thickness material type and thickness Appearance Finish NO Uncoated Areas NO Blisters NO Flux Deposits NO Gross Dross Inclusions NO sharp spikes (hazardous) Continuous, Uniform, Reasonably Smooth Intended Use Clause Handrails Moving Parts Articles to be Painted Adherence & Embrittlement Test susceptible items Test if problem occurs Manage Customer Expectations to Minimize Clean Up Cost

6 Material Category COATING THICKNESS ASTM A123 (ESPESOR DEL RECUBRIMIENTO) <1/16 [<1.6] Steel Thickness Range (Measured) in [mm] 1/16 to <1/8 [ 1.6 to <3.2] 1/8 to 3/16 [ 3.2 to < 4.8] 3/16 to <1/4 [ 4.8 to <6.4] 1/4 to <5/8 [ 6.4 to <16.0] 5/8 [ 16.0] Structural Shapes Strip & Bar Plate Pipe & Tube Wire Rebar

7 A123 TABLE 2: COATING CONVERSION Coating Grade µm mils oz/ft 2 g/m

8 EXAMPLE FOR SINGLE TEST PIECE 1-in Steel Plate Grade 100 required (100 um) for average of all the test pieces Grade 85 required (85 um) for single test piece No minimum for a single gauge reading Gauge Readings: 80 um, 60 um, 120 um, 115 um, 110 um Average Thickness: 97 um Average thickness of test piece > Grade 85 (85 um)

9 WHEN IS INSPECTION REQUIRED? Finish & Appearance Visual Inspection, All Pieces Embrittlement Susceptible items only Adherence Testing Susceptible items only Coating Thickness Not all pieces tested Only test pieces inspected Use ASTM A123 sampling protocol to determine number of test pieces

10 A123 SAMPLING (MUESTREO)

11 Spanish SAMPLING INSTRUCTIONS (INSTRUCCIONES PARA EL MUESTREO) Determine: Lot Size One truck delivery Identical Material Same shift Same kettle Number of Test Pieces (Sample Size) Number of Pieces in Lot Number of Test Pieces (Sample Size) 3 or less all 4 to to 1, ,201 to 3, ,201 to 10, ,001 and over 20

12 TYPES OF TEST PIECES (TIPOS DE PIEZAS EN LA MUESTRA DE CONTROL) Single Specimen Test Pieces One material category One steel thickness range 100,000 mm 2 (160 in 2 ) Multiple-Specimen Test Pieces Multiple material categories Pole with base plate, etc. Multiple steel thickness ranges > 100,000 mm 2 (160 in 2 )

13 Material Category COATING THICKNESS ASTM A123 (ESPESOR DEL RECUBRIMIENTO) <1/16 [<1.6] Steel Thickness Range (Measured) in [mm] 1/16 to <1/8 [ 1.6 to <3.2] 1/8 to 3/16 [ 3.2 to < 4.8] 3/16 to <1/4 [ 4.8 to <6.4] 1/4 to <5/8 [ 6.4 to <16.0] 5/8 [ 16.0] Structural Shapes Strip & Bar Plate Pipe & Tube Wire Rebar

14 A123 TABLE 2: COATING CONVERSION Coating Grade µm mils oz/ft 2 g/m

15 MUESTREO: 100,000 MM 2 (160 IN 2 )

16 MUESTREO > 100,000 MM 2 (160 IN 2 )

17 MULTIPLE SPECIMENS

18 STORAGE (ALMACENAJE)

19 AT THE GALVANIZING PLANT Avoid Peeling Do not stack hot articles Avoid Flaking Thick coatings > um (8-10 mils) Minimize movement Do not drop, hit, or impact Lift with adequate number of lift points (avoid bending) Avoid Wet Storage Stain (WSS)

20 WET STORAGE STAIN (EL ÓXIDO BLANCO) Galvanizing process does not cause wet storage stain Caused by improper storage or inadequate air flow Galvanizer responsible for avoiding formation at plant Galvanizer NOT responsible if developed during transit or after delivery to customer

21 LIGHT & MEDIUM WSS - ACCEPTABLE Mild, light staining in most cases does not need to be cleaned Parts will weather naturally to match unaffected areas Can be cleaned if needed for aesthetic purposes

22 HEAVY WSS NOT ACCEPTABLE Some parts with heavy wet storage staining can be cleaned Most parts must be regalvanized before being put into service

23 WET STORAGE STAIN (BEFORE)

24 WET STORAGE STAIN NATURAL WEATHERING (3.5 MONTHS)

25 CLEANING WET STORAGE STAIN 1. Use cleaning product 2. Brush with a stiff-bristle or nylon brush 3. Rinse immediately with fresh tap water 4. Rinse again 5. Fully dry the parts 6. Check coating thickness 7. Avoid wet storage stain in the future AGA Study Cleaning products that do not damage galvanizing: CLR Lime juice Naval Jelly Rust Dissolver Picklex 10G White vinegar

26 AVOID WET STORAGE STAIN (EVITANDO EL ÓXIDO BLANCO) Elevate and separate articles stacked outdoors with wood spacers (poplar, ash, spruce) Provide adequate ventilation Avoid nested stacking Incline parts for drainage Stagger or cross stack pieces Ensure parts are dry and include humidifying agent before packing in storage containers Avoid stacking on wet soil or decaying vegetation Surface Treatments Chromate quenching Waxes and oils

27 AVOID WET STORAGE STAIN (EVITANDO EL ÓXIDO BLANCO)

28 SUMMARY ASTM A123 requirements: finish, appearance, coating thickness, adhesion & embrittlement Sampling protocol keeps coating thickness inspection requirements manageable Use best practices for handling & storage to avoid unnecessary responsibility for peeling, flaking, and wet storage stain

29 QUESTIONS & COMMENTS American Galvanizers Association Phone: Follow AGA on Social Media: American Galvanizers Association /American-Galvanizers-Association /AGAgalvanizeit Tweet/Post Feedback: #galvanizeit