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+27 (0)11 450 0728


We are committed to delivering excellence

To position the Hot Dip Galvanizers Association of Southern Africa, comprising all its Members and other interested parties, as a professional organization serving the interests of all parties dependant upon the hot dip galvanizing industry. To develop and expand the demand for hot dip galvanizing, identify and develop new market opportunities for the benefit of Members and other Stakeholders.

About the Hot Dip Galvanizers Association

The Hot Dip Galvanizers Association Southern Africa (HDGASA) is a not-for-profit trade association dedicated to serving the needs of specifiers, architects, engineers, contractors, fabricators and hot dip galvanizers throughout Southern Africa.



Provides free technical advice to members relating to their galvanizing plant, equipment, process controls, environmental protection and waste minimisation. Offers training in numerous aspects related to hot dip galvanizing, some of which are only available to members.



The association is a technical information center. Please use this link on our website to access information sheets, codes of practice, steel protection guides and to view case studies. These are at the disposal of specifiers, architects, engineers,  contractors, fabricators and hot dip galvanizers to inform about the benefits of hot dip galvanizing.



The Association is proud to announce that all the back issues of Hot Dip Galvanizing Today are available for download in PDF format. Please note that some of the files are of a large size and will take a few minutes to download.



Presented annually, these awards represent the finest accomplishment in the use of hot dip galvanizing. For each category award, all project partners are considered winners as the nature of hot dip galvanizing is a combined effort, with the final project reflecting the work of many.


Useful Links

Our Association partners with many professional bodies and Associations.



Provide technical assistance to end users, consultants and fabricators as to the appropriate application of hot dip galvanizing and duplex coating systems for corrosion control of carbon steel. Technical assistance and services are provided by means of presentations, inspections, setting of specifications and the provision of training.



The Association is a technical information centre established for the benefit of specifiers, consultants, end users and members. Contact the Association should you require a comprehensive presentation on various aspects of hot dip galvanized coatings including,

  • Introduction to Corrosion
  • Duplex Coatings (zinc + paint)

The contents of the presentation can be tailored to suit the requirements of the audience.


The HDGASA will carry out inspections wherever required for members and their customers.

Technical Evaluations

Provide training and education for member companies to ensure a high standard of quality and service throughout the hot dip galvanizing industry.


Galvpatch is a zinc rich epoxy used for site repairs on hot dip galvanized components.


Metal Pro Galvanized Steel Markers

The marker is a soluble ink based marker used for component manufacture in the fabrication process.



Hot dip galvanizing is one of the most widely used methods of protecting steel from corrosion.  During fabrication and after hot dip galvanizing, the coating is inspected for compliance with the relevant specifications.


Course Schedule

2016 course dates for Introduction to Hot Dip Galvanizing and Certified Inspectors Course Level II



Provides free assistance to members with respect to quality aspects during fabrication, hot dip galvanizing and site inspections. The Association will investigate and objectively report on coating quality issues without compromising its creditability or professional reputation.

Offers technical advice relating to specifications, steels suitable for hot dip galvanizing and the optimum corrosive control measures to suit various environments.



The following case studies are most relevant to South African weather conditions and climate. Please click the links below to obtain further details.

Volume 12, Issue 2: September 2015 (61)

  1. Intergalva 2015: The Global Galvanizing Awards.
  2. Report on Intergalva 2015
  3. Forms of Corrosion: Corrosion due to incorrect selection of materials
  4. Forms of Corrosion: White rust and wet storage stains
  5. Bob’s Banter: The role of mathematics education in industry

Volume 12, Issue 1: May 2015 (60)

  1. Hot DipGalvanizing: A cost effective protection system.
  2. Advertorial:How to achieve savings and a better galvanizing finish with nickel tablets
  3. Rail Fasteners:Performance of hot dip galvanized resilient rail fasteners exposed in a severe marine environment
  4. Reinforcing in Steel: Shouldn’t more rebar be galvanized?
  5. Soil side corrosion
  6. High Strength Bolts:The use of high strength bolting assemblies for pre-loading
  7. Understanding Distortion
  8. Case Study:The performance of Pandrol rail fasteners in a marine environment on the Natal South Coast
  9. Bob’s Banter: Doublespeak

Volume 11, Issue 3: November 2014 (59)

  1. Projects in the Spotlight: Kirstenbosch Tree Top Walkways.
  2. Projects in the Spotlight: Redevelopment of the Tramways Building, Port Elizabeth
  3. Projects in the Spotlight: New Military Health Base Depot
  4. Projects in the Spotlight: The Last Glass House–new residence in Parktown
  5. Projects in the Spotlight: The Druenberg Solar Power Project
  6. Projects in the Spotlight: Blast protection covers at Syferfontein
  7. Projects in the Spotlight: Cellular towers at Cell C Headquarters in Midrand
  8. Projects in the Spotlight: Conveyor river bridges.
  9. Projects in the Spotlight: Uzizi Pedestrian Bridge in the Tugela Ferry District
  10. Projects in the Spotlight: Beth Diane Armstrong; artist
  11. Projects in the Spotlight: New bulk liquid berth and floating breakwater
  12. Projects in the Spotlight: Transformer radiators for Eskom or local authority sub stations
  13. Projects in the Spotlight: Landing Platforms, Saldanha Bay
  14. Bob’s Banter: Achieving our desired future means managing the unexpected
  15. Conference: The use of hot dip galvanizing in mining in Southern Africa (part 3)
  16. Opinion:General galvanizing–how does SA compare globally? (part 2–technology)
  17. On the Couch…. With Mark Thomas and Henry Fagan

Volume 11, Issue 2: November 2014 (58)

  1. Conference: The use of hot dip galvanizing in mining in Southern Africa–part two
  2. Case Study: Eskom Coastal Sub – Stations
  3. Fasteners: Impala Bolt & Nut stays on top of the fastener market
  4. Fasteners:Fastener availability matrix and participating fastener suppliers
  5. General: POLASA fills dire need
  6. Education and Training: Three day Galvanizers Inspectors Course
  7. On the couch …Professor Albrecht Herholdt
  8. Technical: Galvastop – masking of components prior to hot dip galvanizing for the exclusion of the coating.
  9. Member’s Corner: The benefits of chossing zinc for corrosion protection seen from an unexpected source.
  10. Member’s Corner:Steel industry related app launched!
  11. Bob’s Banter: The psychology of health and safety

Volume 11, Issue 1: November 2014 (57)

  1. Conference: The use of hot dip galvanizing in mining in Southern Africa – part one.
  2. Case Study: Eskom Coastal Sub-Stations.
  3. Case Study: Bellville Transport Interchange upgrade built in 2002 stands the test of time.
  4. Duplex: Duplex coating good after 14 years of mild to moderate marine exposure.
  5. Poles & Masts: Leading steel pole manufacturer takes delivery of high-end CNC machines.
  6. Opinion: General galvanizing – how does SA compare globally? Part 1 – The Market.
  7. General: Effectively avoiding weld spatter dramatically increases the quality of the hot dipgalvanized coating.
  8. Technical: The difference between Hydrogen and Strain Age Embrittlement.
  9. Galvpatch successfully exposed to fridge conditions at minus 25ºC for 8 months
  10. Education and Training: Three day Galvanizers Inspectors Course

Volume 10, Issue 4: November 2013 (56)

  1. The World of Hot Dip Galvanizing around Us: American Galvanizers Association – Metrolina Greenhouses, South Campus Central Chiller Plant, Franklin Park Conservatory, Blast Deflectors, Brea Power Plant, Electric Vehicle Rail Tramway, Gibbs Street Pedestrian Bridge, Platt Street Bridge Restoration, Solaris Tower, The Christina and John Markey Memorial Pedestrian Bridge, Winged Glory, WinStar Casino Globe.
  2. The World of Hot Dip Galvanizing around Us: Galvanizers Association of Australia – Making the moment last long, High stakes skin for Star extension, Galvanized finish guards new rail work, From pit to prestige sport centre, Upholding very green park build.
  3. Duplex Coatings: Effective corrosion protection of structural steel
  4. General: Thermal Spray Association of Southern Africa (TSASA).
  5. Education: Three day Galvanizers Inspectors Course
  6. Education: Beware – Salt spray testing! Misleading accelerated corrosion tests
  7. Education: Accelerated test methods applied to zinc coatings in terms of SANS 14713 – 1:2011
  8. Education: Guide to hot dip galvanizing for sustainable design
  9. General: Letter to the Editor
  10. On the Couch …. Robert JW Brusse
  11. Members News: The Advanced Roof and Building Technology Foundation
  12. Members News: What passivation is in practice and what it is not
  13. Members News: Fresh dynamics at Cape Galvanising Consolidated
  14. Members News: Transvaal Galvanisers
  15. Members News: ArcelorMittal involvement in Solar and LSF (Light Steel Frame) Projects
  16. Bob’s Banter: Achieving our desired future means managing the unexpected

Volume 13, Issue 1: April 2016 (62)

  1. Metallurgical investigation into the origin of cracks at welded connections on a hot dip galvanized
    fabricated structural steel perimeter walkway platform.
  2. Galvanizing of steel – all around us.
  3. Design considerations: venting and drainage
  4. Materials of Construction
  5. Purlins manufactured from hot dip coil
  6. Bob’s Banter: What a disappointment – there are no black holes!
  7. Case Study – Rural Pedestrian Bridges
  8. Personality Profile – Bob Wilmot
  9. 2016 Annual Golf Day



What is this?

A small amount of Sodium Dichromate is generally added to the quench water bath for passivation.


Although the recommended quantity of Sodium Dichromate is about 0.15 to 0.3%, occasionally when topping up, more is added.  This often results in a dark yellow to brown colour on the galvanized surface.  The darker colour will provide enhanced initial corrosion protection.

Effect / Remedy / Responsibility

This can be accepted since there is no adverse effect on corrosion control.

The galvanizer should maintain the concentration of Sodium Dichromate at about 0.15 to 0.3%.