Independent R&D for the rolling-stock grease basket Indian Railways, Delhi Metro, Bangalore Metro, Chennai Metro and the new high-speed corridors actually need — axle roller-bearing grease to RDSO M-942 (lithium-complex NLGI 3 with controlled oxidation stability), wheel-flange grease for curve-noise and flange-wear control on freight corridors, pantograph carbon-strip grease for the 25 kV OHE contact interface, traction-motor bearing grease for the DC and AC locomotives, hot-section grease for diesel-locomotive turbocharger bearings, and the maintenance-yard hydraulic and gear oils for wagon repair workshops. Built against RDSO specifications, BIS IS 7623, and the operating spec of CLW Chittaranjan, DLW Varanasi, ICF Chennai, RCF Kapurthala, MCF Raebareli and the major metro depots.
RDSO M-942 is the gating specification. The Research Designs and Standards Organisation (RDSO) at Lucknow, the technical arm of Indian Railways, publishes Specification M-942 for axle roller-bearing grease. The standard fixes penetration, dropping point, copper-strip, oxidation stability and water washout limits and is the qualification specification for every grease used in axle boxes across the Indian Railways fleet. Lithium-complex NLGI 3 on Group I/II mineral base with proprietary EP and oxidation inhibitor is the dominant chemistry that passes M-942. A manufacturer must be RDSO-approved to supply.
Wheel-flange lubrication is now a curve-wear cost problem. Freight corridors on the IR network (DFCC, Mumbai-Howrah, Kalka-Shimla) and heavy-haul corridors (Coal corridors in Jharkhand, iron-ore in Goa-Karnataka) see severe flange wear at curves. Wayside applicators (Portec, Lincoln Industrial style) deposit a controlled film of biodegradable wheel-flange grease at the gauge face. On-board applicator systems use solid grease sticks. The lubricant must adhere, transfer cleanly to the rail head, retain through 1000-1500 axles after application, and not contaminate the wheel-rail running tread (which would compromise traction and braking).
The 25 kV OHE interface demands conductive grease. The pantograph carbon strip sliding on the OHE contact wire at 100 to 130 km/h must maintain electrical continuity for the traction current (1500-3000 A peak). Dry running burns the carbon strip rapidly. The carbon-filled conductive grease keeps the interface lubricated, conductive and arc-resistant. The grease must hold up to ozone and UV exposure on the strip, and the carbon particle distribution must be controlled to maintain resistance.
Traction-current bearing fluting is a real failure mode. A traction motor armature bearing carries stray current from the rotor circuit; if the grease is too conductive, the current arcs through the bearing rolling elements and produces electrical-discharge pitting (fluting) on the raceway. The grease must be dielectric enough to break the circuit but lubricous enough to protect at 5000 rpm continuous. We engineer dielectric strength above 25 kV (IEC 60156) into traction-motor greases. See our grease formulation service.
| Product | Standard / Specification | Issuing Body | Where It Applies |
|---|---|---|---|
| Axle Roller Bearing Grease | RDSO M-942 | RDSO (Indian Railways) | Freight wagon and passenger coach axle boxes |
| Locomotive Lubricant | RDSO LM · Locomotive Maintenance Manual | RDSO | Diesel and electric loco lubricant matrix |
| Wheel Flange Grease | RDSO M-046 / equivalent metro spec | RDSO / DMRC | Wayside and on-board flange applicator |
| Pantograph Carbon Grease | RDSO Specification (Electric Loco) | RDSO | 25 kV AC traction OHE contact |
| Traction Motor Grease | RDSO M-940 series · IEC 60156 | RDSO / IEC | DC and AC traction motor bearings |
| Lubricating Grease · India | BIS IS 7623 | BIS | General industrial-grade grease conformance |
| Metro Rolling Stock | DMRC / BMRCL / CMRL Technical Spec | Metro Authorities | City metro coach lubricant |
| Hydraulic Oil · Workshop | BIS IS 11656 · DIN 51524 Pt 2 HLP | BIS / DIN | Coach factory and workshop hydraulics |
| Gear Oil · Loco | BIS IS 1012 · API GL-5 | BIS / API | Diesel loco gear-train and reduction gear |
RDSO M-942 is the Research Designs and Standards Organisation Specification M-942, the Indian Railways standard for roller-bearing grease used in rolling-stock axle bearings — freight wagons (BOXN, BCN, BOBR), passenger coaches (LHB and ICF), and EMU/MEMU stock.
The standard fixes penetration (220-250 worked), dropping point (260C minimum), oxidation stability (under 5 psi pressure drop in 100 hours D942), water washout, and copper-strip limits. Qualification against M-942 is the entry point to supplying Indian Railways through the RDSO-approved vendor mechanism.
Lithium-complex (LiX) NLGI 3 per RDSO M-942 has been the Indian Railways standard for decades. It is well understood, cost-effective at the IR procurement scale, and gives 3 to 5 year service intervals between greasing.
Polyurea is increasingly chosen for metro and high-speed coach applications (Vande Bharat, Rajdhani LHB) because of its higher dropping point (280C plus), longer oxidation-stable life, and freedom from soap-derived ash. For metros, the bearings are sealed-for-life cartridge type and polyurea is the dominant choice.
Tell us which railway products you need (axle grease, traction motor, pantograph, wheel flange) and whether you are targeting RDSO or metro vendor lists. We respond within one business day.