Hamriya Free Zone, Sharjah,
PO Box: 49714, United Arab Emirates.
Land Line : +971 42524938

Email: info@seltecuae.com




Synthetic fire - resistant hydraulic fluids based on organic esters, type HFDU, rapidly biodegradable. PLANTOFLUX AT/ S are fire resistant hydraulic fluids with self-extinguishing properties. These are synthetic fluids formulated with organic esters and specifically selected additives. They do not contain mineral oils and are free from toxic and unpleasant smelling decomposition products. PLANTOFLUX-AT-S have a higher flash and combustion point than traditional, mineral oil-based hydraulic oils and are specifically designed to reduce the risk of violent explosion when in contact with open flames r hot metal surfaces. The high viscosity index, constant at all time, provides good lubrication performance in an extremely wide operating temperature range. PLANTOFLUX-AT-S offer high oxidation and ageing resistance, excellent corrosion protection and anti-wear properties, low foaming tendency, rapid water separation and consequently reduction of water and oil sludge. PLANTOFLUX-AT-S are nontoxic, biodegradable over 90% according to CEC-L-33-A93 and not included in the CEC list of the hazardous products subject to labeling. PLANTOFLUX-AT-S has also excellent biodegradation of > 60% according to OECE 301B. PLANTOFLUX-AT-S are Factory Mutual Research approved as less flammable hydraulic fluids and listed in the Group 1 of the Approval Guide (approval procedure no. 3014386).


PLANTOFLUX-AT-S are primarily used as fire resistant hydraulic fluids in machines or plants operating in hazardous conditions, i.e. where naked flames or high temperatures are present and the fire risk caused by the fluid leakage is high, most notably: steel mills, blast furnaces, continuous casting machine, coke plants, etc.PLANTOFLUX-AT-S are generally applicable in any hydraulic systems where environmental protection and biodegradability are a priority. PLANTOFLUX-AT-S are miscible and compatible with conventional mineral oils, therefore a change to PLANTOFLUX-AT-S is possible at any time. Please contact our Technical Assistance. The compatibility with Nitrile, Teflon, Viton and Silicon elastomers is good, whereas the use of Neoprene, Ethylenepropylene, Butyl and Isoprene seals and hoses is not commonly recommended.Before filling the hydraulic circuit with PLANTOFLUX-AT-S it is important to know whether the fluid used previously was a mineral oil, a phosphate ester or a different one, such as water-glycol or inverted emulsion.

Mineral oil - Owing the miscibility and compatibility of PLANTOFLUX-AT-S with mineral oils, only draining before replacement is required. In case of relevant presence in the hydraulic system of deposits and sludge, a preliminary flushing with PLANTOFLUX-AT-S is recommended. Filters should be cleaned or replaced.  

Phosphate esters-PLANTOFLUX-AT-S is miscible and compatible with phosphate esters, therefore the same procedure as for mineral oils can be followed. The compatibility with PLANTOFLUX-AT-S of elastomer components, i.e. seals, hoses, etc., present in the system, must be controlled in advance in the FUCHS' technical assistance laboratories.

Other fluids (water base)-Procedure for replacement is different depending on the fluid type. Please contact our technical department.

PLANTOFLUX-AT-S fluids possess a very high oxidation resistance and are able to resist for a long time to thermic-oxidative conditions, without suffering alterations of relevance. The joined action of metals, water and pollutant can accelerate the oxygen attack at high temperature, therefore, in order to get the best performances of the in service fluid, it is advisable to maintain it well cleaned and free of water. The temperature should not exceed 70 °C - 90 °C in the tank and in the operating parts of the hydraulic system. Temperature peaks of 90 °C are tolerable only for a short period of time. A periodical control of the in-use product is recommended by means of samples to be tested in FUCHS' laboratories. Our Technical Assistance will advise the customer on the best suggestions according to the test results.


  • HFDU fluid according to DIN 51502, based on synthetic esters.
  • Factory Mutual Research approved (approval procedure no. 3014386) HFDU


  • Rapidly biodegradable (> 90% in 14 days, CEC-L-33-A-93, > 60% according to OECD 301B)
  • Non-toxic, physiologically harmless, free of heavy metals
  • Excellent EP-/AW-properties, excellent wear protection (Vickers 1000 h Test no wear)
  • Excellent resistance to ageing and oxidation
  • Excellent viscosity-temperature characteristics, high natural viscosity index, shear stable (VI > 180)
  • Rapid air release, low foaming
  • Excellent corrosion protection

Typical technical data:

Product   46 AT- S 68 AT -S 69 AT -S
Properties Unit     Test Method
Appearance - Clear Clear  
Color AS TM 1.5 1.5 DIN ISO 2049
Viscosity at 40 °C mm2/s 48 69 DIN EN ISO 3104
Viscosity at 100 °C mm2/s 9.6 12.7 DIN EN ISO 3104
Viscosity Index - 190 187 DIN ISO 2909
Density at 20 °C kg/m2 918 928 DIN 51 757
Pourpoint °C -35 -32 DIN ISO 3016
Acid number mgKOH/g 1.2 1.5 DIN 51 558
Foaming characteristics
Sequ. I to III
24 °C immed./after 10 min
93.5 °C immed./after 10 min
24 °C after 93.5 °C
immed./after 10 min



ASTM D 892
ASTM D 892

ASTM D 892
Oxidation stability (100 °C, 350 h)
viscosity variation
% 6 6 Inhouse Test
Demulsibility min 12 16 DIN ISO 6614
Rust prevention,
Stages A and B
degree of
no rust (pass) no rust (pass) DIN ISO 7120
Copper strip test degree of
1a 1a DIN EN ISO 2160
Cleanness level Class 7 7 NAS 1638


Inflammability characteristics:

Product   46 AT- S 68 AT -S  
Properties Unit     Test Method
Flashpoint (COC)  °C 270 280 DIN ISO 2592
Fire point   °C 338 358 ASTM D 92
Spray ignition test
(Factory Mutual)
- Pass Pass Factory Mutual
Hot surface ignition test
 (Factory Mutual)
- Pass Pass Factory Mutual
Spray ignition test
(National Coal Board)
- Pass Pass National Coal


Tribological characteristics:

Product   46 AT- S 68 AT -S  
Properties Unit     Test Method
Four ball test - welding kg 200 220 ASTM D 2783
Four ball test - wear mm 0.35 0.35 ASTM D 4172
Falex EP, breakage at lbs 2400 2400 ASTM D 3233
Reichert Value: wear mm2 14 14 Inhouse Test
FZG mechanical gear test rig
FZG A/8,3/90
failure load
12 12 DIN ISO 14635-1
Vickers vane pump test, weight loss ring and vanes    250 h test
                                  1000 h test
mg 16
DIN ISO 20763
DIN ISO 20763