Series Features of Slow Quenching Oil
The slow oil quenching oil is formulated from refined secondary hydrocracking base oil with antioxidants, boasting good thermal oxidation stability, maintaining long-term stable cooling properties, and a long service life.
The oil quenching oil has a short vapor film stage, moderate cooling rate at high temperatures, and a slower cooling rate at low temperatures. This allows for high and uniform surface hardness as well as sufficient case depth, while also effectively controlling quenching deformation.
Slow oil quenching oil provides medium to large workpieces with high and even surface hardness, as well as sufficient case depth, while also effectively controlling the workpiece's quenching deformation.
The slow oil quenching oil provides good brightness to the workpiece after quenching, with minimal loss and low cost of use.
Slow Quench Oil Series Classification
DR-365 Isothermal Gradual Quenching Oil (for low-temperature use), DR-355 Isothermal Gradual Quenching Oil (for medium-temperature use), DR-355S Isothermal Gradual Quenching Oil (for high-temperature use)
Slow Oil Series | Model | Open FlashDot （℃） | Largest ColdPlease provide the Chinese content that needs to be translated into American English. （℃/s） | Low Temperature Cooling Rate （300℃,℃/s） | Kinematic Viscosity （mm2/s） | Utilize warmthDegree （℃） | Typical Application Scope |
Isothermal grading quenching oil (For Low-Temperature Use) | DR-365 | ≥230 | ≤95 | ≤5 | 70-80 | 80-120 | Significantly reduces quenching distortion in thin-walled, complex-shaped parts such as car gears, motorcycle gears, clutch plates, and bearing rings, thereby improving product accuracy, reducing machining allowances of the workpieces, and significantly lowering production costs. |
Isothermal分级quenching oil (For Medium Temperature Use) | DR-355 | ≥245 | ≤85 | ≤4.5 | 90-120 | 80-130 | High deformation requirement tools made of medium and low alloy steel, carburized steel, etc., quenching, clutch plates, prestressed shims, bearing rings, motorcycle connecting rods, crankshafts, shaft pins, and small module electric vehicle gears, etc. |
Isothermal分级quenching oil (For High-Temperature Use) | DR-355S | ≥265 | ≤80 | ≤4 | ≥180 | 80-160 | Highly complex tooling, spring retainers for weapons, clutch plates, prestressed clips, thin-walled bearing rings, small module electric vehicle gears, knitting industry's textile needles, and other highly complex products |
Slow Oil Series Cooling Characteristic Curve
Our company utilizes the Swedish-imported Smart Quench II Type IVF cryo-accelerator, offering authoritative testing data with excellent reproducibility, high sampling frequency, and cooling property testing conducted in accordance with ISO 9550 standards.
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(Low Temperature Isothermal Quenching Oil)
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Medium temperature isothermal quenching oil
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High-Temperature Isothermal Segregation Quenching Oil
Isothermal分级Quenching Oil Application
DR-365 isothermal hardening oil offers high cooling rates at high temperatures and low cooling rates at low temperatures, suitable for carburizing, carbonitriding, or isothermal hardening of workpieces with minimal deformation. It is applicable for quenching of workpieces with larger moduli, such as electric vehicle gears, automotive and motorcycle gears, and bearing rings with thick walls. It is also suitable for carburizing or carbonitriding quenching of workpieces with poor hardenability and high hardness requirements in the core, such as materials like 20Cr, 20CrMo, 20CrMnTi. Additionally, it is applicable for quenching of small and medium-sized bearing rollers and rings like GCr15, GCr15MnSi, and for tempering of medium carbon alloy steels with relatively thick walls, such as 40Cr, 42CrMo, 35CrMo, and 40CrNiMo.
DR-355 isothermal hardening oil features lower cooling rates at high and low temperatures, suitable for carburizing, carbonitriding, or isothermal hardening of workpieces with minimal deformation. It is ideal for quenching small module electric vehicle gears, automotive and motorcycle gears, and thin-walled bearing bushes, such as materials like 20Cr, 20CrMo, 20CrMnTi, 20CrMnMo, 20CrNiMo, 20Cr2Ni4, etc. It is also suitable for quenching small bearing rollers and bushes like GCr15 and GCr15MnSi.
DR-355S isothermal hardening oil features lower high-temperature and low-temperature cooling rates, suitable for carburizing, carbonitriding, or isothermal hardening of workpieces with minor deformation. It's ideal for quenching of small modulus electric vehicle gears, automotive and motorcycle gears, thin-walled bearing rings, and other components such as 20Cr, 20CrMo, 20CrMnTi, 20CrMnMo, 20CrNiMo, 20Cr2Ni4, GCr15, and GCr15MnSi. It is also applicable in the knitting industry for items requiring high deformation resistance, such as textile needles.
Quenching Oil Usage Standards and Maintenance Management
It is recommended to agitate the quenching oil using a pump or propeller, but not with compressed air, as it accelerates oil oxidation. The heater power should not exceed 1.5 W/cm2 to prevent overheating and premature failure due to the formation of a polymer insulating layer on the heater.
Condensers, pumps, mixing components, piping, and quenching tank parts should not be made of copper or copper alloys to prevent the accelerated oxidation and aging of quenching oil. Steel, stainless steel, or nickel-plated, tin-plated parts can be used instead.
Oil Temperature Control: Monitor or control the oil temperature using instruments to maintain it within the recommended operating temperature range. For quenching tanks used in batch or continuous quenching, a cooling system should be installed. Copper or copper alloys have an aging effect on oil and should not be used as radiators. When selecting a cooler, it is recommended to choose an air cooler. If a plate heat exchanger is chosen, ensure that it does not leak. To extend the life of the oil, choose the lowest possible operating temperature while meeting the quenching requirements.
Pay special attention to prevent water from mixing with the oil. Water in the oil can cause quenching soft spots, significant workpiece deformation, and even cracking, and it is also prone to generate foam in the oil, which may lead to fires or even explosions.
Packaging and Storage
Products passing the factory inspection should be used within twelve months; if not used before the expiration, they can be used only after re-inspection and passing.
Isothermal grading quenching oil is available in 200-liter iron drums or 1000L IBC plastic drums, for indoor storage (temperature range: 5-40°C).
