Hot Dip Galvanizing Suppliers, Saudi Arabia

What does a Saudi buyer get from hot dip galvanizing?

A Saudi buyer gets steel that has been pickled, fluxed and dipped in molten zinc, so every surface, inside tubes and behind welds as well as outside, carries a zinc layer bonded to the steel. It is one of the main routes in surface treatment in Saudi Arabia and it is ordered with a fabrication package for transmission steel, substations, pipe supports, gratings, fencing and building frames.

Two documents define the work. ISO 1461:2022 covers fabricated iron and steel dipped in a zinc melt holding no more than 2 percent other metals; it took over from the 2009 edition and leaves out continuously galvanized sheet and wire, tube from automatic plants and products with their own standard, such as fasteners. ASTM A123/A123M covers structural shapes, strip, bar, plate, pipe, tube, wire and rebar, singly or as assemblies.

Fabrication comes first: see metal fabrication services and structural steel suppliers. Galvanizing then protects what they make.

How much zinc will the steel receive?

The steel section decides it, because ASTM A123 grades minimum thickness by steel thickness and category. For structural shapes the minimum average is 45 microns under 1.6 mm, 65 microns from 1.6 to under 3.2 mm, 75 microns from 3.2 to under 6.4 mm, and 100 microns at 6.4 mm and above. Strip, bar and plate reach 100 microns only above 16 mm.

These are floors. Heavy steel tends to carry more zinc than the grade requires. The finish has to be continuous and free from blisters, flux and heavy dross, and rejected work, other than for embrittlement, may be stripped and dipped again. Request the plant's thickness readings by batch, not a single certificate for the month.

What should the design office check before dipping?

Check venting, draining and size. The American Galvanizers Association states that design and fabrication are the responsibility of the designer and fabricator, and that the galvanizer needs customer approval for extra work such as drilling vent holes. Skipping this step is the usual cause of delays at Saudi plants.

• Closed hollow sections need vent and drain holes at the high and low points, or zinc cannot flow and trapped air is dangerous.
• Kettle fit. Towers and long beams may require double dipping; ask each plant for its longest single-dip length.
• Weld overlaps. Fully seal-welded lap joints trap acid, so use open or vented details.
• Marking. Use stamped or weld-on tags that survive pickling.
• Distortion. Slender plate can move in the hot bath, which is general engineering practice; discuss bracing with the plant.

Does galvanized steel last in Saudi coastal and desert air?

It lasts well in both, but the rate of zinc loss differs and the specification should reflect the site. ISO 12944-2 sets out how to classify atmospheres by corrosivity, and Jubail, Ras Tanura, Yanbu and Jeddah sit in saltier, more humid air than Riyadh or Qassim. On the coast, specify a higher thickness or a duplex system for steel that is hard to maintain.

In a duplex system the zinc and the paint or powder coat protect each other. The American Galvanizers Association reports a service life of about 1.5 to 2.3 times the sum of the two coatings, and at least a 50 percent longer paint life over zinc. For the coating side, read powder coating services in Saudi Arabia; for steel too big for a bath, thermal spray coating is the alternative. Heavy blasting before paint is covered under shot blasting and sand blasting.

Which approvals and specifications matter in Saudi Arabia?

Quality is governed by the owner's specification more than by a single national certificate. Checked as of 2026, confirm current rules with your client and the relevant authority.

Inspection options are covered under coating inspection in Saudi Arabia. For imported structural steel and certificates, the guide to SASO and SABER certificates for industrial equipment is a useful reference, though galvanizing quality itself comes from the project specification.

How do you pick a galvanizing plant?

Pick by capacity, reach and records. Galvanizers are concentrated near Dammam and Jubail, with others around Riyadh and Jeddah, and trucking long steel across the Kingdom adds cost and handling damage.

• Request kettle dimensions, longest single dip, and monthly tonnage.
• Ask how it handles vent hole additions and who signs off.
• Check the repair procedure for damaged zinc, and ask for a witnessed first batch on large orders.

The guide to sourcing industrial suppliers in the UAE and Saudi Arabia adds general vetting steps. To get comparable offers, post your requirement for hot dip galvanizing.

What decides cost and lead time in Saudi Arabia?

Price is quoted per tonne, with higher rates for small or complex work. Zinc price, steel weight, section thickness, double dipping and the plant backlog all matter. Projects that drop large tonnages at once, such as line and plant packages, can queue for weeks, so book capacity when the fabrication programme is set.

Allow time for inspection, repair of local defects, and transport. Protect galvanized steel in storage and loading with nylon slings and timber separators, because wet stacking of galvanized sections can leave white deposits on the zinc.

Sources

• American Galvanizers Association, ASTM A123/A123M overview and thickness grades
• American Galvanizers Association, products covered by ASTM A123
• ISO 1461:2022, hot dip galvanized coatings on fabricated iron and steel articles (Genorma)
• American Galvanizers Association, duplex systems: paint or powder coating over HDG
• ISO 12944-2:2017, classification of environments (Genorma)