QISHANR 5GS Premium Heavy-Duty Mineral Refrigeration Oil 1L - ISO 100 Naphthenic Compressor Lubricant

Company Introduction

Guangzhou Qishanr Technologies Co., Ltd. is a professional manufacturer and supplier focusing on R&D, production and sales of high-performance refrigeration lubricants, base oils and functional additives. With over 10 years of production experience, our self-owned brand QISHANR features excellent compatibility and interchangeability with mainstream compressors. Our products are SGS certified and comply with international industry standards, widely used in air conditioning, ultra-low temperature refrigeration and heat pump systems. We provide professional model selection technical support and flexible OEM / ODM customization services, delivering reliable and cost-effective lubrication solutions for global customers.

Quick Summary

QISHANR 5GS is an ISO VG 100 naphthenic mineral refrigeration oil with a kinematic viscosity of 100 cSt at 40°C, a flash point of 190°C (COC), and a pour point of -30°C. It is formulated for water-cooled air conditioning screw compressors and large industrial refrigeration systems operating with R22, R717 (ammonia), R290, or R600a refrigerants. QISHANR 5GS serves as a direct replacement for Bitzer B5.2, Suniso 5GS/5GSD, York/Frick E, McQuay F, and Fusheng FS100M specifications, and is the highest viscosity grade in the QISHANR GS mineral oil series.

QISHANR 5GS Refrigeration Oil Overview

QISHANR 5GS belongs to the GS Series (Naphthenic Mineral Refrigeration Oil) product line, formulated with selected highly-refined naphthenic base oils. As the highest viscosity grade (ISO VG 100) in the series, 5GS delivers 100 cSt kinematic viscosity at 40°C — approximately 1.8x that of the 4GS grade (56 cSt) — providing the maximum bearing film strength available in the GS series for the largest industrial compressors. Its wax-free naphthenic composition ensures reliable low-temperature fluidity down to -30°C pour point, while the flash point of 190°C (the highest in the GS series) maintains thermal stability at compressor discharge temperatures up to 150°C without carbon deposit formation. Specifically designed for water-cooled air conditioning screw compressors, and fully interchangeable with Suniso 5GS/5GSD specifications. Cross-referenced with Bitzer B5.2, York/Frick E, McQuay F, and Fusheng FS100M.

Key Features & Benefits

• ISO VG 100 — Highest Viscosity in GS Series: 100 cSt kinematic viscosity at 40°C and 8.4 mm²/s at 100°C provides the maximum oil film thickness in the GS series, maintaining hydrodynamic lubrication in screw compressor bearings with shaft diameters above 80 mm where ISO VG 56 or lower grades produce insufficient film strength.
• 190°C Flash Point — Thermal Stability Under Load: Maintains thermal stability at discharge temperatures up to 150°C with a Cleveland Open Cup flash point of 190°C, preventing carbon deposit formation at discharge valves and ports in screw compressors operating at 80-95% load capacity for extended periods.
• Wax-Free Naphthenic Base Oil: Contains less than 0.5% wax content, preventing flocculation in oil-refrigerant mixtures at evaporator temperatures as low as -40°C. Maintains clean oil return through suction lines and oil separators in systems with piping runs exceeding 50 meters.
• -30°C Pour Point for Cold-Start Reliability: Flows reliably at temperatures 20°C below typical evaporator conditions, ensuring oil circulation during compressor cold starts and preventing oil starvation in systems with extended off-cycles in ambient temperatures down to -20°C.
• 918 kg/m³ Density for Controlled Miscibility: Density of 918 kg/m³ at 20°C provides predictable phase behavior with R22 and R717 refrigerants, enabling accurate oil separator sizing and reliable gravity-based oil return in vertical riser configurations.
• High Dielectric Strength for Motor Protection: Provides electrical insulation exceeding 25 kV/2.5 mm breakdown voltage, safe for direct contact with motor windings in semi-hermetic compressors rated up to 500 kW without risk of electrical tracking or short circuits.
• Anti-Deposit Additive Package: Inhibits varnish and sludge formation on bearing journals and thrust surfaces, prevents blockage of oil ports (minimum 0.8 mm diameter) and capillary tubes, extending oil change intervals to 8,000+ operating hours under normal conditions.
• Bitzer B5.2 Direct Replacement: Meets Bitzer B5.2 viscosity, flash point, and pour point specifications. Also cross-references Suniso 5GS/5GSD, York/Frick E, McQuay F, and Fusheng FS100M — covering ISO VG 100 mineral oil requirements across 5 major OEM compressor platforms.

Technical Specifications

QISHANR GS Series Viscosity Grade Comparison

Selection guideline: Choose the viscosity grade specified by your compressor OEM. Higher viscosity grades (5GS) provide greater film strength for larger bearing clearances but increase viscous drag; lower grades (3GS) reduce friction losses in smaller compressors but may not protect adequately in high-load industrial applications.

Applications & Refrigerant Compatibility

Compatible Refrigerants: CFCs (R12, R502), HCFCs (R22), R717 (Ammonia), R600a (Isobutane), R290 (Propane), and other traditional refrigerants requiring mineral oil lubrication.

Compressor Types: Specifically designed for water-cooled air conditioning screw compressors and large industrial compressors where ISO VG 100 viscosity grade is specified by the OEM. Also suited for heavy-duty reciprocating compressors and high-capacity scroll compressors in commercial and industrial HVAC systems with motor ratings above 200 kW.

Typical Applications:

• Water-cooled air conditioning screw compressor systems in large commercial buildings and industrial facilities
• Heavy-duty industrial refrigeration systems (cold storage warehouses, food processing plants, chemical process cooling)
• Large-capacity ammonia (R717) refrigeration systems with high compressor discharge temperatures
• Central chiller plants and district cooling systems requiring maximum viscosity protection

Real-World Application Examples: Commonly specified for Bitzer CSH series screw compressors in R717 ammonia cold storage systems operating at evaporator temperatures of -35°C to -25°C. Also used in York YCIV centrifugal chillers and McQuay water-cooled screw units in district cooling plants serving 50,000+ m² commercial complexes. In food processing facilities, 5GS lubricates Fusheng screw compressors running R22 at condensing pressures above 18 bar, where the 100 cSt viscosity maintains adequate oil film at bearing temperatures exceeding 90°C.

OEM Equivalent Cross-Reference

QISHANR 5GS is a direct replacement for the following OEM-specified ISO 100 mineral refrigeration oils:

For additional OEM cross-references or to confirm compatibility with your specific compressor model, please contact our technical support team with your compressor make, model, and current oil specification.

Why Choose QISHANR 5GS?

• SGS Certified Quality: Independently tested by SGS to verify viscosity (100 cSt ±5%), flash point (190°C minimum), and pour point (-30°C maximum). Batch-to-batch consistency maintained through in-house viscosity blending tolerance of ±3% across annual production of 6,000 tons.
• Viscosity Selection Guidance: Our engineering team helps you select the optimal grade — 3GS (ISO VG 32, 29 cSt) for household and light commercial compressors, 4GS (ISO VG 56, 56 cSt) for medium-duty commercial systems, or 5GS (ISO VG 100, 100 cSt) for water-cooled screw compressors and large industrial systems above 200 kW.
• 6,000-Ton Annual Production Capacity: Established partnerships with international naphthenic base oil suppliers guarantee stable raw material supply. Typical lead time is 7-15 days for standard packaging, 20-30 days for OEM/private label orders.
• OEM & Private Label Services: Support personalized packaging design, custom viscosity blending, and private label services. Minimum order quantity starts at 500 kg for bulk and 200 units for retail packaging.
• Complete Export Documentation: Provide MSDS, Certificate of Origin (CO), SGS test reports, and transportation identification reports (UN3082 classification) for smooth international shipping and customs clearance in 60+ countries.
• Flexible Logistics: Sea freight, land transport, air freight, and express delivery options available. Direct factory-to-destination port or door-to-door service with DDP/CIF/FOB terms.

Frequently Asked Questions

Q: What is the difference between QISHANR 4GS and 5GS?
A: QISHANR 5GS has a kinematic viscosity of 100 cSt at 40°C (ISO VG 100), which is approximately 1.8 times the viscosity of 4GS at 56 cSt (ISO VG 56). This higher viscosity produces a thicker hydrodynamic oil film on bearing surfaces, which is required by large water-cooled screw compressors with bearing clearances above 0.05 mm. Additionally, 5GS has a flash point of 190°C compared to 185°C for 4GS, providing greater thermal margin at discharge temperatures that can reach 130-150°C in heavily loaded screw compressors.

Q: Can QISHANR 5GS replace Bitzer B5.2 or Suniso 5GS?
A: QISHANR 5GS is formulated to match the Bitzer B5.2 specification in all key parameters: ISO VG 100 viscosity class, naphthenic mineral base oil, 190°C minimum flash point, and -30°C maximum pour point. It is fully interchangeable with Suniso 5GS/5GSD, York/Frick E, McQuay F, and Fusheng FS100M without requiring system flushing when replacing the same viscosity grade. For Bitzer CSH and CSW series compressors, QISHANR 5GS meets the B5.2 oil charge requirements listed in the Bitzer maintenance manual.

Q: Is QISHANR 5GS suitable for water-cooled screw compressors?
A: QISHANR 5GS is specifically formulated for water-cooled air conditioning screw compressors, which represent its primary application. The 100 cSt viscosity at 40°C provides the robust bearing film strength required by screw compressors with rotor diameters of 100-300 mm, while the 190°C flash point ensures no thermal decomposition occurs at discharge temperatures of 80-120°C typical of water-cooled systems. The wax-free naphthenic formula also prevents oil separator fouling in systems with oil injection rates of 5-15 liters per minute.

Q: Is QISHANR 5GS compatible with ammonia (R717) refrigeration systems?
A: QISHANR 5GS is fully compatible with R717 ammonia systems and is widely used in industrial cold storage operating at evaporator temperatures of -35°C to -10°C. Naphthenic mineral oils are the standard lubricant type for ammonia compressors because ammonia is immiscible with mineral oil, requiring the high viscosity of 100 cSt to maintain lubrication despite minimal refrigerant dilution. The 190°C flash point provides adequate thermal margin for ammonia systems where discharge temperatures commonly reach 140-160°C due to ammonia's high heat of compression ratio.

Q: Can QISHANR 5GS be mixed with 3GS or 4GS?
A: All three grades in the QISHANR GS series use the same naphthenic mineral base oil type, so mixing does not cause chemical incompatibility or additive precipitation. However, blending 5GS (100 cSt) with 4GS (56 cSt) or 3GS (29 cSt) produces an intermediate visco that may not meet the OEM specification for either grade. For example, a 50/50 blend of 5GS and 4GS yields approximately 75 cSt, which falls outside both ISO VG 56 and ISO VG 100 tolerance bands. A complete oil change with the correct single grade is recommended when switching viscosity specifications.

Q: What packaging sizes are available for QISHANR 5GS?
A: Standard packaging includes 1L, 4L, 5L, 18.9L (5-gallon pail), 20L (drum), and 200L (barrel) options. All containers are sealed with tamper-evident closures and nitrogen-blanketed to limit moisture content below 30 ppm during storage. Custom packaging sizes and private-label printing are available for orders above 200 units, with typical production lead time of 20-30 days.

Q: How can I place an order or request a sample?
A: Contact us through our website inquiry form, email, or WhatsApp. Sample quantities of 1-4 liters are available for laboratory evaluation or field testing, typically shipped within 3-5 business days via international express. For bulk orders (minimum 500 kg), we offer CIF/FOB/DDP pricing with payment terms of T/T 30% deposit and 70% against copy of bill of lading. Our technical team provides free viscosity grade selection consultation based on your compressor model, refrigerant type, and operating conditions.

Technical content reviewed by QISHANR Lubrication Engineering Team. Last updated: May 2026.