Stainless steel surface treatment · Rotterdam
Grinding, polishing, pickling and passivation of cargo tanks, tank containers, heating coils and piping. On site, in port or on board, with a passivity test to prove it.
Pick the object. You see what we usually find on it and how we fix it.
Stainless cargo tanks on board, before the next load or after damage. We work inside the tank itself.
ISO tank containers for chemicals and food. We restore the stainless surface so the tank is clean and passive again.
Coils (serpentines) inside cargo tanks. Deposits and corrosion tend to sit in the bends and at the welds.
Stainless pipes, bends and flanges. After welding we restore the protective layer.
Tanks and vessels in process industry, food and pharma. A smooth, passive surface that stays clean.
Stainless and aluminium silos for food, chemicals and bulk goods. Aluminium we clean and polish; stainless we also pickle and passivate.
Exhaust gas cleaning systems on board. The acidic wash water attacks the stainless, especially at welds and spray nozzles. We clean, repair and passivate.
The damage we see most often, how you recognise it and what we do about it.
Small, deep pits, often with a rust rim. On tank floors and where liquid splashes.
Chlorides and acids break through the protective layer locally.
Rust in seams, under gaskets and flanges or between overlapping plates.
Oxygen runs out in tight gaps, so the protective layer cannot recover.
Straw, bronze or blue bands next to the weld.
Welding heat creates an oxide scale that is low in chromium.
Rust spots or rust traces shortly after installation or repair.
Iron particles from tools, grinding dust or nearby carbon steel.
An even dull, brown or grey surface over a larger area.
Aggressive cargo or cleaning agents attack the whole surface.
Deep scratches or a rough surface (high Ra) that dirt clings to.
Mechanical damage, the wrong abrasive, or wear.
Crystallised residue, green or black discolouration after acidic cargo.
Residue from earlier cargo, such as phosphoric acid, stays behind and attacks the steel.
Stainless steel protects itself with a thin chromium oxide layer. Welding, scratches and dirt break that layer. We remove the damage and let the layer form again.
From photos or on site: which steel, which damage, which approach.
Remove corrosion, pits and deep scratches mechanically.
Smooth the surface so dirt has less to hold on to.
Remove heat tint and oxide scale chemically.
Let the protective chromium oxide layer form again.
A passivity tester shows whether the surface is passive.
Not every object needs every step. We choose the steps that solve the problem.
We assess the condition of the stainless steel and record the damage with photos and a report. You get advice on cleaning or treatment, also for ship surveys and claims.
After an aggressive or sensitive cargo we make the tank clean and passive: residue out, discolouration gone, rust removed. The surface is then ready for the next load.
A pipe inside a tank, before and after passivation. Our own work.
Before
After passivation
After passivation we measure the surface with a passivity tester. You can see that the steel is protected again, without taking our word for it.
Photos of our work on board, in port and on site.
A Rotterdam family business with 30 years in the trade. Corrosion and discolouration are undone, leaving a clean, passive surface.
David I. Ramos has worked with stainless steel since 1996. In 2010 he founded Irmãos Cleaners, specialised in surface treatment: cargo tanks, tank containers, silos and scrubbers.
The name is Portuguese: irmãos, brothers. That spirit has stayed: a small team that knows and trusts each other.
We work where the steel is: inside the tank, on board the ship, at the depot or in the plant. Pickling and passivation means handling acids, so full protective gear is always standard.
You speak directly with the specialist who carries out the job. No layers in between, no call centre.
A photo of the damage, the object and the location is enough to start. You will quickly hear what it needs.
+31 6 2493 6355