Armite Lead-Plate 250
LP-250 is a sealing compound that prevents seizing or galling at temperatures ranging from -350°F to 2987°F (-212°C to 1641°C). LP-250 is particularly useful for materiales, which gall easily, such as aluminium and stainless steel.
This compound consists of pure lead powder suspended in a non-volatile hydrocarbon vehicle and does not dry out, even when exposed to the atmosphere. Because lead is one of the least reactive of the metallic elements, the compound is highly non-contaminative and is impervious to the effects of salt, water, steam, oils, ammonia and hydrocarbons. LP-250 is only prohibited from use with pure oxygen and Freon gases.
Suggested Applications
Threads, boilers, refinery units, steam and gas turbines, pipe sealing applications, rifle sear pin.
Characteristics
Anti-Corrosion Quality
LP-250 not only has a high corrosion resistance, it also prevents oxidation and corrosion in the materials to which it is applied. This quality makes it a standard for all-around use in chemical plants and reï¬neries.
Anti-Seize and High Temperature Qualities
The compound remains as an effective anti-seize compound, even to the fusing or melting point of the surrounding metals. The hydrocarbon vehicle melts away between 600° to 700° leaving only the pure lead, which becomes liquid at about the same temperature. On cooling, the lead solidiï¬es as a ï¬ne metallic ash and still retains its lubricating and sealing qualities. Recommended uses include steam and gas turbines, reï¬nery units, boilers, railroads and aircraft.
Low Temperature Use
The compound forms an effective seal for equipment handling liquid nitrogen at -350°F (212°C).It is recommended for pipe sealing applications at temperatures to -100°F (37°C).
High Pressure Applications
Increasing pressure causes lead particles to pack more closely, strengthening the seal. LP-250 has been tested up to 100,000 PSI hydraulic fluid lines. The use of gaskets and ï¬ller compound (LP-250F) may be required if ï¬tting tolerances are too liberal or if the high pressure ï¬tting threads are coarse.
Anti-Seize (Metal to Metal)
LP-250 prevents a corrosion weld between metal to metal surfaces. This feature is important for maintenance of heavy industrial equipment.
Anti-Galling or Anti-Freezing
The compound forms a thin, pure-lead coat on metal while ï¬lling all voids and smoothing the surface. Friction is greatly reduced and less torque is needed for assembly and disassembly. Because the joined metals are isolated from moisture and oxygen, deterioration by galvanic action is impossible. In the same manner hydrogen embrittlement is prevented.
Lubricating Qualities
LP-250 is valuable as a lubricant in many tapping, machining, and metal-forming jobs. It is not recommended as a bearing lubricant except for very loose journal bearings, as LP-250’s plating action will freeze close-tolerance bearings.
