Rotor seal element with heat resistant alloy coating

In rotary machinery, including a wear ring seal member stationarily mounted in a holding member so as to extend generally coaxially about a rotatable cylindrical member in substantially sealing relationship with the surface of said rotatable cylindrical member, said rotatable member being made of a low alloy carbon steel, the improvement,

• wherein the surface of said rotatable cylindrical member is substantially completely covered by a fused welding alloy coating metallurgically bonded thereto,
• said weld coating being formed of a heat and corrosion resistant alloy composition containing by weight:
• up to about 0.25% C, about 0.5% to 5% Mn, 0 to about 5% Fe, 0 to about 1% Si, 0 to about 1% Cu, about 0.1 to 1% Ti, about 10% to 30% Cr, about 0.5% to 5Nb+Ta and the balance at least about 60% Ni.

In a multi-stage compressor for compressing chlorine gas comprising a plurality of impellers with hubs supported coaxially by a rotatable shaft, including a series of wear ring seal members each stationarily mounted in a holding member so as to extend generally coaxially about each of said impeller hubs in substantially sealing relationship therewith, said impellers being made of a low alloy carbon steel, the improvement

• wherein the hub surface of each of said impellers is substantially completely covered by a fused welding alloy coating metallurgically bonded thereto,
• said weld coating being formed of a heat and corrosion resistant alloy composition containing by weight about 10% to 30% Cr and the balance at least about 60% Ni,
• whereby said low carbon steel is protected against ignition due to heat of friction in the presence of chlorine gas.