Allowable Chlorine Content in SS Equipment

Are you sure you're not confusing chlorine (free) with chloride ion? (as in ordinary salt)

Drinking water (treated, out the tap) is usually less the 1 ppm free chlorine, and you can smell it then. That's in the West, it might be different in Mumbai but not 20 ppm.

Any water source usually contains chloride ions. If I remember right the WHO limit for drinking water is 500 ppm or thereabouts. Seawater has about 15000 ppm (as Cl^-) and attacks ordinary stainless steel. 20 ppm chloride seems a bit overcautious to me but if that's what the spec says....

Cheers..........Codey

Free chlorine in drinking water is usually around 0.2 - 0.5ppm at most. Municipal swimming pool water is approaching 2ppm and is undrinkable at that chlorine level.

Chloride ion levels depend upon the water source. There isn't usually a problem hydro-testing stainless steel vessels on potable water, the analysis for which may be easily had in most districts where a utility company supplies it.

OK PW, I couldn't remember the exact free chlorine level and said 1 ppm as a covering figure. To reassure OP it wouldn't be anywhere near 20 ppm

Cheers.......Codey

ashraf3ali:

Stainless steal equipment may be tested using "potable" water (that is water with a chloride content less than 250 or so mg/kg) only if it is dried immediately afterwards or it is flushed with demineralised water, condensate or boiler feedwater and dried.

My suggestion is that to avoid any danger of cracking that you pressure test with any Austenitc (or any other SS for that matter) with demin water, condensate or boiler feed water. These waters should have a chloride content of less than 2 mg/kg.

You are confusing Chlorine with Chloride. You mean Chloride content.