Defender Hydraulic HFC / HFC hydraulic fluid

Defender Hydraulic HFC — Fire-Resistant Water-Glycol Hydraulic Fluid

What Is Defender Hydraulic HFC

Defender Hydraulic HFC is a water-glycol hydraulic working fluid. It transmits power in a hydraulic system while providing the fire-resistant performance expected from an HFC-type fluid.
The product is not a concentrate. Its formulation is set during production, so no water or other components need to be added before the hydraulic system is filled.

Main Characteristics

What Does HFC Mean

HFC is a class of fire-resistant water-glycol hydraulic fluids. These fluids are used in industrial systems where the working fluid may be exposed to high-temperature surfaces, open flames, or molten metal.
The HFC designation identifies the fluid type and its functional role. It does not mean that any hydraulic system can be converted from mineral oil to HFC without checking the equipment requirements.

Key Parameter — 39 mm²/s Viscosity at 40 °C

The kinematic viscosity of Defender Hydraulic HFC is 39 mm²/s at 40 °C. Viscosity is an important parameter for lubrication conditions and for the operation of pumps, valves, and other hydraulic-system components.
When selecting the fluid, compare the actual viscosity of Defender Hydraulic HFC with the requirements specified by the equipment manufacturer. HFC classification alone does not replace a viscosity and compatibility check.

Low-Temperature Properties

The pour point of Defender Hydraulic HFC is −42 °C. This value characterizes the fluid’s low-temperature flow behavior.
The pour point must not be treated as a guaranteed minimum start-up or continuous operating temperature for a hydraulic system. Actual permissible start-up and operating temperatures also depend on equipment design, pump type, seals, load, and the manufacturer’s requirements.

When Defender Hydraulic HFC Is Appropriate

Defender Hydraulic HFC should be considered for industrial hydraulic systems where hydraulic performance must be combined with increased fire-safety requirements.
• metallurgical equipment;
• foundry equipment;
• hydraulic presses and other equipment operating near high-temperature sources;
• systems located near molten metal or open flames;
• other industrial hydraulic systems for which HFC-class fluids are permitted by the equipment manufacturer.

When Another Hydraulic Fluid Is Required

Defender Hydraulic HFC should not be selected simply because the equipment is hydraulic. If the machine manufacturer requires mineral hydraulic oil, an anhydrous synthetic fire-resistant fluid, or another fluid class, replacing it with HFC requires a separate technical assessment.
HFC fluid is also not a heat-transfer antifreeze for heating or cooling systems. A water-glycol base and low-temperature flow behavior may appear similar, but Defender Hydraulic HFC is formulated to function as a hydraulic working fluid.

Compatibility with the Hydraulic System

Before filling the system with Defender Hydraulic HFC, confirm that the equipment manufacturer permits the use of HFC water-glycol fluids.
Particular attention should be paid to compatibility with pumps, valves, seals, hoses, coatings, filter materials, and other system components. Requirements intended for mineral hydraulic oils must not be automatically transferred to an HFC system.

Conversion from Mineral Hydraulic Oil

When converting from mineral oil or another hydraulic-fluid type, residual old fluid and contamination should be minimized.
Before conversion, check the equipment manufacturer’s requirements for the changeover procedure, system materials, and acceptable residual content of the previous fluid. If required, clean the system according to the plant’s technical procedure or the equipment manufacturer’s instructions.
Do not mix Defender Hydraulic HFC with another hydraulic fluid unless compatibility has been verified.

System Preparation

1. Confirm that the equipment permits the use of HFC-class hydraulic fluid.
2. Check the condition of the reservoir, piping, filters, seals, and other system components.
3. If required, remove the previous working fluid and contamination according to the equipment maintenance procedure.
4. Do not add water to Defender Hydraulic HFC before filling.
5. Fill the system with the ready-to-use fluid to the level specified by the equipment manufacturer.
6. After start-up, check for leaks, pump and valve operation, fluid level, and other hydraulic-system control parameters.

How to Use

Defender Hydraulic HFC is supplied ready to use. Fill the prepared hydraulic system without prior dilution.
The required fill volume, operating level, start-up procedure, and monitoring parameters are determined by the documentation for the specific equipment.

Mixing and Dilution

Do not dilute Defender Hydraulic HFC with water before use.
Changing the water-to-glycol balance can alter viscosity, low-temperature behavior, corrosion-control performance, and fire-resistant properties.
Adding water or another fluid should only be carried out within a separately established system-maintenance and fluid-control procedure.

In-Service Monitoring

The condition of an HFC fluid should be monitored during service. Water-glycol hydraulic fluids can change in properties due to water evaporation, contamination, ingress of foreign fluids, or extended operation.
Monitoring intervals and acceptable parameter limits should be defined by the equipment requirements and the plant maintenance procedure. If the working fluid moves outside the permitted limits, determine the cause before adjustment or replacement.

What the pH, Density, and Boiling Point Mean

The pH of Defender Hydraulic HFC is 9.0–9.5 at 20 °C, and its density is 1.078 g/cm³ at 20 °C. These values can be used as product control parameters.
The initial boiling point is approximately 100 °C. This value is not the maximum permissible continuous operating temperature of the hydraulic system and should not be used to define the equipment temperature limit.

Limitations

• Do not dilute the product with water before filling.
• Do not use in equipment where HFC-class fluids are not permitted by the manufacturer.
• Do not mix with mineral or other hydraulic fluids without a compatibility check.
• Do not interpret the −42 °C pour point as a guaranteed minimum equipment start-up temperature.
• Do not interpret the initial boiling point of approx. 100 °C as the permissible continuous operating temperature.
• Do not use as a heat-transfer antifreeze in place of a specialized heating or cooling fluid.

All machine tool coolants can be selected from the following link

 Storage and Safety

The recommended storage temperature for Defender Hydraulic HFC is 5–40 °C. Keep containers tightly closed and protect the product from contamination, excessive heat, direct sunlight, and unsuitable storage conditions.
During handling, avoid eye contact, prolonged skin contact, and ingestion. Select personal protective equipment according to workplace conditions and the product documentation.
Do not allow uncontrolled release into soil, drains, or surface water.

FAQ

Is Defender Hydraulic HFC a concentrate?
No. It is a ready-to-use hydraulic fluid and does not need to be diluted with water before filling the system.
What does HFC mean?
HFC is a class of fire-resistant water-glycol hydraulic fluids used in industrial systems where reducing fire risk is important.
Can Defender Hydraulic HFC replace ordinary hydraulic oil?
Not automatically. First confirm that the equipment manufacturer permits HFC fluids and that the system materials are compatible with a water-glycol hydraulic fluid.
Do I need to add water before use?
No. The product is supplied with its working formulation already set. Do not add water before filling.
What does a −42 °C pour point mean?
It describes the fluid’s low-temperature flow behavior. It is not a guaranteed minimum start-up or continuous operating temperature for a specific hydraulic system.
Can Defender Hydraulic HFC be used as antifreeze?
No. It is an HFC hydraulic fluid. Heating and cooling systems require a specialized heat-transfer fluid.
What is the viscosity of Defender Hydraulic HFC?
Its kinematic viscosity is 39 mm²/s at 40 °C.

Ordering and Selection

Before ordering Defender Hydraulic HFC, check the equipment manufacturer’s requirements for hydraulic-fluid type, viscosity, and approval of HFC-class fluids.
If the system is being converted from mineral oil to HFC, selection should also take into account pump type, seals, operating temperature range, previous fluid, and the system-cleaning procedure.