In the hot-dip galvanizing process, steel is completely coated with corrosion-inhibiting zinc, which forms a highly abrasion-resistant metallurgical bond with the base steel. In order to ensure that all interior and exterior surfaces are protected from corrosion, entire steel fabrications are lowered into and raised…
Month: October 2018
Reasons for Duplex Coating
There are seven good reasons to paint or powder coat hot-dip galvanized steel: Extended Durability – in what is called the synergistic effect between galvanized steel and paint, the zinc of the galvanized coating is a barrier protection to the substrate steel, cathodically protects it,…
Saudi Aramco Signs Deals Worth Over $34B
Saudi Aramco has announced that it has signed 15 Memoranda of Understanding (MoU) and strategic and commercial collaborations valued at more than $34 billion. The deals, which can be seen below, are with 15 international partner companies and entities from eight countries in three continents:…
Meeting Expectations When Selecting Concrete Rehabilitation Systems
Meeting Expectations When Selecting Concrete Rehabilitation Systems By Mike Dadik, P.E. S.E., Carollo Engineers, Inc. By itself, concrete has enormous compressive strength but little tensile capacity. Thus, an unreinforced concrete column can support a large load, but a beam has minimal strength without reinforcing steel.…
UNDERWATER WELDING
UNDERWATER WELDING
Difference between quality assurance and quality control
Quality assurance and quality control are two aspects of quality management. While some quality assurance and quality control activities are interrelated, the two are defined differently. According to ISO 9000:2015: Quality management systems—Fundamentals and vocabulary: Quality assurance consists of that “part of quality management focused…
Quality assurance and audit functions
Auditing is part of the quality assurance function. It is important to ensure quality because it is used to compare actual conditions with requirements and to report those results to management. In The Quality Audit: A Management Evaluation Tool (McGraw-Hill, 1988), Charles Mill wrote that…
Weld Slag Clean Up Requirements for Galvanizing
When welded structures are hot-dip galvanized, the weld area cleanliness significantly affects the quality and appearance of the galvanized coating around the weld. If a coated electrode (i.e. a flux-coated welding wire/rod/stick) is used during welding, all welding flux and slag must be cleaned prior…
Sags/Runs
Downward movement of paint soon after application on vertical surfaces Common Causes Over application Excessive thinning Poor workmanship Remediation While wet, sags/runs should be smoothed with a paint brush If dry, abrade, clean, and apply spot coat
BLUSH
Haze or oily residue on the surface of a coating Common Causes High humidity or cold temperatures during application Curing stages of an epoxy Intensified by cool temperatures and increased coating thickness Remediation Blush will effect adhesion of topcoat If blush is detected (not easy…