Hydraulic Oils

Choosing a hydraulic oil for Iraqi conditions

Step one: the ISO grade

The ISO VG number is the oil's viscosity at 40 °C, and the grade has to satisfy the pump manufacturer's viscosity window at the temperature the oil actually reaches in the reservoir — not the temperature of the air. An excavator working near Basra in July can run tank oil at 80 °C or above; the same machine starting at dawn in Sulaymaniyah in January is close to freezing.

• ISO VG 22 and 32 — indoor industrial systems, machine tools, circuits with oil coolers, and mobile equipment used mainly in the cooler months.
• ISO VG 46 — the general-purpose grade, and what most mobile and industrial systems specify.
• ISO VG 68 — sustained high oil temperature, worn pumps with increased clearances, and construction machinery working through the Iraqi summer where the manufacturer permits it.
• ISO VG 100 and 150 — slow-moving, heavily loaded systems and combined circulation duty.

The manufacturer's specification always comes first. Where a range is allowed, choose on measured reservoir temperature. And where one machine faces both a cold start and a hot afternoon, the answer is not a compromise grade but a high viscosity index oil — Cyclon HYDRAULIC SP or SP/ZF — which holds its viscosity across the swing.

Step two: the right family

• HYDRAULIC RX — the workhorse anti-wear oil to DIN 51524 Part 2 HLP, with a broad approval list including Bosch Rexroth RE 90235, Eaton and Danieli. Available from ISO VG 10 to 150 and correct for most systems calling for an HM or HLP fluid.
• HYDROPREMIUM — anti-wear with EP and anti-corrosion performance, approved for combined hydraulic and circulation duty (AGMA 9005-E02 RO, Cincinnati Machine P68/P69/P70, Denison HF-0 and HF-1). Use it where one oil has to serve both a hydraulic circuit and a lubrication circuit.
• HYDRAULIC SP — high viscosity index, all-season, to AFNOR NF E48-603 HV. For equipment that starts cold and runs hot within the same shift.
• HYDRAULIC PURE — the same performance profile built to NAS 5 cleanliness. For new machine fills, servo and proportional valves, and any system with fine filtration where built-in contamination is the real risk.
• HYDRAULIC HLP-D — zinc-free detergent and dispersant fluid whose purpose is tolerating contamination: machine tools where water-mixed cutting fluid enters the hydraulics, and excavators, loaders and dozers working where dirt and water ingress cannot be prevented.
• HYDRAULIC ZF — zinc-free, very high purity, with strong demulsibility and approvals including US Steel 127 and 136 and VDMA 24318. The opposite strategy to HLP-D: water separates so it can be drained. Specified where zinc is unacceptable, typically steel and heavy industry.
• HYDRAULIC ZF XP — Group II hydrotreated base oils with a zinc-added anti-wear package, exceeding Bosch Rexroth RE 90235 with Eaton 35VQ25 and Parker Denison T6H20C vane pump performance. For casting, forging, mining, cement and construction plant, and for marine and mobile hydraulics including excavators and cranes. Despite the name, this is not a zinc-free oil — see the warning below.
• HYDRAULIC SP/ZF — zinc-free and high viscosity index together, to DIN 51524 Part 3 HVLP. For presses, lifts, marine systems and heavy machinery that need both properties.
• HYDRAULIC R2 — the HYDROPREMIUM performance profile manufactured with re-refined base oils, for customers with sustainability requirements written into their tender.
• CYBIO-HFE — fully synthetic, rapidly biodegradable ester fluid to ISO 15380 (HEES) with EU Ecolabel criteria and US EPA VGP acceptance. For sites where a leak reaches water or soil that matters.
• HYDRAULIC HFDU — fire-resistant synthetic ester to ISO 12922 HFD-U, with inherent self-extinguishing properties. For steel production, foundries and mining, where a burst hose could meet a hot surface.

Do not mix families. Zinc-free and zinc-containing oils use different additive chemistry, and ester fluids are not compatible with mineral oils. Changing family means draining and flushing, never topping up.

Read the names carefully: HYDRAULIC ZF and HYDRAULIC ZF XP are not the same chemistry. HYDRAULIC ZF is zinc-free. HYDRAULIC ZF XP is formulated with a zinc-added anti-wear package. Where a system specification calls for an ashless or zinc-free fluid, the correct products are HYDRAULIC ZF or HYDRAULIC SP/ZF. When ordering, state the full product name rather than the abbreviation.

Step three: the conversation that saves the customer money

In Iraqi operating conditions, most hydraulic pump and valve failures are caused by dust and water entering the system rather than by the quality of the oil. That makes the useful discussion on site a housekeeping one:

• Store drums sealed, upright and under cover. A drum left outside will draw in water as it breathes with the day and night temperature swing, and any water pooled on the head goes in with it.
• Never decant in the open or through an unfiltered funnel. One top-up during a dust storm can undo a year of clean running.
• Fit and maintain reservoir breathers. It is the cheapest reliability improvement available on any machine.
• Look at the oil. Cloudiness is water, and water does more damage than heat.
• Take a sample at each service on machines that matter. Particle count and water content tell you whether the problem is the oil or the housekeeping.

Frequently asked questions

Not sure which product a vehicle, machine or fleet needs? Try the Cyclon oil selector, or send us the details and we will specify it in writing.