Ingersoll-Rand 100-200 HP/75-160 KW, 125-200 HP/90-160 KW technical manual

Recommended equipment for on-site analysis includes a thermometer, pH meter, and dissolved oxygen meter. Dissolved oxygen and temperature must be measured on-site and it is recommended that pH be measured on-site. All other analyses should be performed by a professional water quality analyst. The Langelier Index (Ll) is calculated using the following equation and the tables found on the following pages.

Ll = pH - (9.30 + Total Dissolved Solids chart value + Temperature chart value ) + Hardness chart valve + Alkalinity chart value)

The Ll is zero when the water is in chemical balance. If the Ll is greater than zero, there is a tendency to form scale. If the Ll is less than zero, the water tends to be corrosive.

Dissolved oxygen may be controlled in closed cooling towers. Several types of treatments are commercially available to remove dissolved oxygen. For open cooling towers, dissolved oxygen is not an easily controlled parameter. Also, a filtration system is recommended for the water going into the air compressor when using an open cooling tower.

It should be noted that Ingersoll-Rand’s guidelines and recommendations should be used in evaluating the water systems and the problems that may occur in the normal operation of our air compressors. If water problems persist or are not covered above, you should consult a professional.

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