boiler water gauge glass failure analysis

[chumet1]

i have a 200psi locomotive boiler with water level gauge glasses breaking every 2-3weeks. i am new to the section (3months) and apparently this problem is a new phenomenon which just started about 6-8mnths back. the problem started when there was a new supplier of these glasses. we have reverted back to the old supplier but we have had 5glass failures in the past 2months. my question is, does water quality affect gauge glass service life?? because from the water analysis, most of the water quality specs. are out of range from the required specs. the following is a summary of water quality i got from the lab over a period of 2weeks, the recommended specs are shown in brackets:
P.H range=12.4 (<10.5); Total dissolved solids = 1460-2280ppm (2000-3500); M.alkalinity = 1460-2550ppm (250-850); P.alkalinity = 730-1490ppm (250-650); C.alkalinity = 325-1035ppm (100-300); total hardness = 0 (0-25); chloride = 2100-3400ppm (0-800); sulphites = 70-80ppm (30-90)

 

[moltenmetal]

pH that high will RAPIDLY dissolve glass, regardless who makes it. Probably not in a period of a week or two, but rapidly.

Even neutral water will dissolve glass in a 200 psig steam system over time. Corrosion rates could be in the 10s of mils per year. Gauge glasses, depending on design, can sometimes be fitted with mica protection sheets to reduce corrosion rate.