Mobil Pyrogard D is a high performance water-based hydraulic fluid designed to meet the requirement for economical fire-resistant hydraulic fluids in general industrial applications. It consists of an oil phase surrounding finely divided water droplets uniformly dispersed throughout the mixture. This ensures that only the oil phase, not the water, contacts and lubricates moving parts, thereby minimizing wear. Such inverted emulsions have a higher viscosity than conventional oil-in-water emulsions. The additive system used provides a high level of wear protection and resistance to corrosion and the formation of gums and resins.

The fire resistant properties of Mobil Pyrogard D derive from its water content. Even when the fluid is sprayed at a pressure of over 200 bar / 3000 psi from a diesel engine fuel injector into a propane flame, it will not ignite. The emulsions are extremely stable and, during normal storage, will exhibit very little water separation and only a minor amount of oil separation. Mild agitation or normal service usually will return any separated oil to the emulsion. The emulsion has a white appearance, which highlights points of leakage so that they can be repaired promptly to minimize fluid loss.

Its versatility and excellent performance record make Mobil Pyrogard D a fluid of choice among users.

Mobil Pyrogard D is an important member of a brand of fire-resistant hydraulic fluids that have provided outstanding service, worldwide, in the most demanding of applications. Mobil Pyrogard D was developed in conjunction with hydraulic equipment builders to meet the needs of applications in which fire-resistance properties and lubrication performance are key requirements. Pyrogard D offers the following benefits:

Features	Advantages and Potential Benefits
Excellent Fire resistance	Increased safety for personnel and plant
Antiwear characteristics comparable with good mineral antiwear oils	Minimum pump and valve wear, less downtime
Good protection against rust, corrosion and oxidation	Freedom from deposits on pump parts and screens; reduced maintenance
Excellent multi metal compatibility	For use with a wide range of pump designs including steel, aluminum and copper alloy construction
Compatible with seal materials normally used in hydraulic systems	Minimized change-over costs from mineral products
Resistant to bacterial and fungal activity	Do not require special biocides or fungicides, except when introduced into an unusually dirty system
Emulsion has white appearance	Highlights points of leakage for rapid repair and minimal fluid wastage

When filling Mobil Pyrogard D into a system that has previously used petroleum fluid or water/glycol type fluid, it is essential to clean the system thoroughly before introducing the new product. While Mobil Pyrogard D is compatible with both Viton and Buna N (nitrile) rubbers, it should not be used with butyl rubber, leather, natural rubber, cork composition materials or fabric-reinforced packing.

Operation at temperatures between 4ºC and 55ºC will ensure good performance. Because of the possibility of water evaporation from the products, bulk fluid temperatures above 65ºC are not recommended. The water content is important and must be maintained at a minimum of 38% to retain optimum fire resistance properties. As water evaporates, the viscosity of the fluid decreases. Increasing the water content thickens the emulsion and increases its viscosity. This peculiar characteristic of water-in-oil emulsions makes it doubly important to maintain the proper water content to ensure the correct viscosity and wear protection as well as fire resistance. Under normal operating conditions, water evaporation is very slow and water addition to restore fire resistance will only be necessary at extended intervals.

Mobil Pyrogard D is recommended for use in hydraulic systems using suitable gear, vane or piston pumps in applications with close proximity to sources of ignition. Equipment manufacturers' instructions should be observed. It finds particular application in steel mills, mines and die-casting and other industrial applications. Specific applications include:

• Hydraulic shears, automatic welders, core machines, presses, trim presses and injection molding machines
• Continuous miners, conveyors and rock breakers
• Die-casting machines, hoists

Based on available information, this product is not expected to produce adverse effects on health when used for the intended application and the recommendations provided in the Material Safety Data Sheet (MSDS) are followed. MSDS's are available upon request through your sales contract office, or via the Internet. This product should not be used for purposes other than its intended use. If disposing of used product, take care to protect the environment.