• Identification markings on fabricated items should be carefully prepared before galvanizing so that they will be legible after galvanizing.
• Do not use paint to apply addresses, shipping instructions, or job numbers on items to be galvanized. Oil based paints and crayon marks are not removed by the pickling acids. In-shop identification can be accomplished with soapstone or special water soluble markers.
• Use a deep stenciled steel tag loosely wired to the fabrication.
• Stamp the surface of the item using die-cut deep stencils or series of center punch marks.
• Use a series of weld beads to mark letters or numbers directly to the fabrication.

Internal Venting:
Please fabricate as indicated in illustration to the right.

Pipe Coatings:

Pipe commonly presents two special galvanizing problems:

• The "mill-coating" (varnish, lacquer and similar materials) applied by the manufacturer costs extra to remove at the galvanizing plant. If possible order uncoated pipe from your supplier.
• Welding of mill-coated pipe burns and carbonizes the varnish in the surrounding heated areas. This "soat" must be removed by blasting or other mechanical means.

Welded Items

When welded items are galvanized, an uncoated electrode should be used wherever possible to prevent flux deposits. If a coated electrode is used, all welding flux residues must be removed by wire brushing, chipping, grinding, or abrasive blast cleaning.

Flux residue removal is normally the fabricator's responsibility unless other arrangements have been made. Welding rods high in silicon may cause excessively thick and/or darkened coatings to form in the welded area.

External Venting

Any pipe or tubular fabrication must be suitably vented as indicated. Each vent hole must be as close to the welds as possible. Please consult with Reliable Galvanizing for your specific requirements.

Combining Different Materials and/or Surfaces

Optimum galvanizing quality is seldom obtained when different surface conditions, different fabricating methods, or ferrous metals with different chemistries are combined.

Minimizing Distortion

• Some fabricated assemblies may distort at the galvanizing temperature as a result of stresses induced during fabricating of the steel.
• Where possible, use symmetrical rolled sections in preference to angle or channel frames. I-Beams are also preferred.
• Use parts in an assembly that are of equal or near equal thickness, especially at joints.
• Continuous weld joints using balanced welded techniques to reduce uneven thermal stress.
• Try to avoid designs which require double-dip galvanizing. Consult Reliable if you anticipate a wide variance of section size.
• We can also advise you regarding the use of temporary bracing and/or reinforcing to minimize or prevent warpage and distortion during galvanizing.

Drainage

For effective galvanizing, cleaning solutions and molten zinc must flow into, over, through and out of the fabricated article.

Failure to provide for this free, unimpeded flow is a frequent cause of problems, for both galvanizer and customer. Improper design for drainage results in galvanizing of poor appearance and in excess build up of zinc which is unnecessary and costly.

Tanks and Semi-Enclosed Products

Closed top tanks and cylinders must be adequately vented to allow free flow of zinc and eradicate any air or zinc traps. Venting of 2" minimum diameter holes must be provided in diametrically opposite corners of the tank.

Moving Parts

When a galvanized assembly incorporates moving parts, a radial clearance of not less than 1/16" (1.59mm) must be allowed to ensure full freedom of movement after the addition of zinc during galvanizing.

On hinges, all adjacent surfaces must be ground 1/32" on both pieces to allow for thickness increase during galvanizing. Grinding both pieces is necessary.

Overlapping Surfaces

All edges on overlapping surfaces should be seal-welded. This prevents internal rusting and "bleeding". A vent hole through both members is also necessary. This is the prevent any moisture which gets in through a pin hole in the weld from building up pressure and exploding.

Threaded Parts

• Bolted assemblies should be sent to Reliable Galvanizing while in the disassembled condition.
• Internal threads of nuts must be tapped oversize after galvanizing to accommodate the increased diameter of the bolts.
• To remove excess zinc and produce smoother coatings, small parts including fasteners are centrifuged in Reliable's "Spin-a-Batch."