(A solution for direct acting tensioners and all other motion compensation applications)

HOUGHTO-SAFE NL1 is a water Glycol fire resistant hydraulic fluid that has been designed to meet the demanding conditions seen in direct acting riser tensioner systems. This is largely due to its high levels of mixed hydrodynamic and boundary lubrication additives and has been validated in long-term OEM cylinder tests. Degradation of hydraulic fluid (evidenced by accelerated reduction in pH) has been observed in some DAT/N-Line systems. Such degradation contains the formation of sticky, high viscosity, black residues that contain metal fines. Metal fines have been shown to react with organic acidic additives within water glycol fluids – under certain conditions, this can result in the observed black residues. These residues are of concern as they may deposit around sealing elements. It is also of concern that deposits might reach the interiors of anti-recoil valves and cause the system to fail.

HOUGHTO-SAFE NL1 has been formulated to minimise such residues and maintain a stable pH over a 5 years period. Moreover, the cylinder bore surface is often uncoated, untreated low-alloy carbon steel that has reduced
corrosion and corrosive wear resistance under lower pH conditions.

Features / Benefits

  • Passes Def Stan 91-110 Annex D for compression ignition at a 40:1 ratio.
  • Excellent pH stability for 5 years plus in demanding environments.
  • Great lubricity validated in long-term OEM cylinder tests.
  • Avoid PU and FKM/FPM.
  • Cefas D OCNS Rating.
  • Compatible with most commonly used elastomers.
  • Corrosion resistant in liquid and vapour phase.
  • Can be used as a preservation fluid for up to 5 years.
  • Compliant with Global environment regulations.


  • Direct acting-tensioners
  • Motion compensators


HFC-Water Glycol

Data (Typical Values)

FormFluorescent Pink Transparent Liquid
Specific Gravity1.08
Kinematic Viscosity (cSt)

Corrosion ASTM D665BPass
Corrosion ASTM D5534Pass (500hrs)

Health and Safety

Refer to SDS for proper handling and disposal. Please note that the SDS includes handling, health and disposal information which should be passed on to your employees, and to anyone else who comes in contact with the product. Additional advice can also be
obtained from your local Houghton representative.
NOTE: Read and understand all precautions on container labels before using this product.


  • EPA-GoM

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