Marine grease must resist salt-water washout (D1264 <2%), salt-spray rust (D665B pass) and seawater immersion. Calcium sulfonate complex (CaSX) is the technology choice — inherently hydrophobic, with built-in corrosion inhibition and EP capability. Used in stern tube bearings, deck winch, anchor windlass, cargo crane, rudder, propeller cutless bearing, marine valve stem, boat trailer wheel bearing and jet-ski bearings. This guide gives the CaSX marine BOM, Indian application map and salt-water performance targets.
| Component group | Typical role | Typical share |
|---|---|---|
| Base oil(s) | Carrier fluid (mineral / synthetic / bio) | ~75–90% |
| Thickener / soap system | Builds structure & consistency (NLGI grade) | ~8–15% |
| EP / anti-wear additive package | Load-carrying & wear protection | ~2–6% |
| Antioxidant, corrosion inhibitor, tackifier | Service life, rust protection, adhesion | balance |
Indicative high-level composition only. The exact components, treat rates, performance additives and approved suppliers are shared under NDA as part of a Lubechem formulation engagement.
Process: pre-gel CaSX with 4% water at 80-95 °C; in-situ complexing with Ca(OH)2 + 12-HSA + boric at 130 °C; dehydrate 140 °C; cool to 90 °C and add EP/AW/AO/CI/tackifier; mill to NLGI 2. QC against full ASTM lubricant & grease testing: drop no-drop (>300 °C), penetration 270-285, 4-ball weld 400 kgf, D1264 water washout <2%, D665B salt-water pass, D4048 1A-1B. The EP/AW/AO/CI stack here is drawn from a balanced grease additive package. Ex-works cost ₹220-340 / kg.
Marine waterproof grease is grease formulated to resist salt-water washout, salt-spray corrosion and water emulsion contamination. Used in marine applications — stern tube bearings, deck winch, anchor windlass, cargo crane slewing, rudder bearing, propeller shaft cutless bearing, marine valve stem, boat trailer wheel bearings, jet-ski bearings.
Distinguished by: water washout (D1264) <2% (vs <15% for general industrial), salt-water rust prevention (D665B) pass, copper strip in seawater 1B, and corrosion stability over 7-30 day immersion. Standard thickeners: calcium sulfonate complex (CaSX — best water resist), aluminium complex, calcium 12-hydroxystearate (legacy).
NLGI 2 CaSX marine grease BOM (%): Group II 220N 58%, overbased Ca sulfonate TBN 400 24%, Ca(OH)2 1.5%, 12-HSA 4%, boric acid 0.5%, sulphurised olefin EP 3%, ZDDP 1.5%, phenolic AO 0.5%, aminic AO 0.5%, imidazoline CI 1%, ASA 0.5%, TTA 0.05%, Ca nitrite 0.5%, PIB tackifier 0.8%, polyisoprene 0.8%, blue dye 100 ppm.
CaSX inherent water resistance + imidazoline + Ca sulfonate vapour-phase CI give D1264 <2%, D665B salt-water pass. Drop no-drop / >300 °C, 4-ball weld 400 kgf.
CaSX is the technology choice for marine grease because: (1) Inherent water resistance — the sulfonate is naturally hydrophobic; (2) Inherent corrosion inhibition — Ca sulfonate has built-in vapour-phase CI; (3) Inherent EP capability — calcium carbonate micelle gives weld load >315 kgf without additional EP; (4) No drop point; (5) Excellent shear stability.
Disadvantages: cost (₹360-580 / kg vs lithium ₹180-280). For non-critical marine applications, aluminium complex or calcium 12-OH can substitute at lower cost — but CaSX remains the OEM premium choice. Producers planning a CaSX line should also factor in the wider grease plant setup cost for the high-temperature complexing reactor it needs.
ASTM D665B (synthetic seawater rust prevention) — grease applied to standard steel rod, partial immersion in synthetic seawater + stirring at 60 °C for 24 hr. Pass = no rust visible. Marine grease must pass D665B (more aggressive than D665A distilled water).
Achieved by combination of high tackifier (water film displacement), imidazoline CI (salt-water specific), and inherent water-resistance of CaSX thickener. Critical for marine applications where salt spray and seawater immersion are routine.
International brands: Castrol Marine MPL, Shell Gadus S2 V100 2 Marine, Mobil SHC Polyrex, Klüber Marine, Lukoil Marine grease. PSU: IOCL Servo Marine Lube, BPCL Mak Marine. Indian marine grease volume: Indian Navy / Coast Guard maintenance, merchant marine bunker depots (Mumbai, Cochin, Visakhapatnam, Kandla, Chennai, Paradip, Mangalore), Indian inland waterway, fishing trawler fleet (Kerala, Tamil Nadu, Andhra), boat-trailer aftermarket (Goa).
₹280-650 / kg branded. Lubechem custom marine CaSX (LC-GR-CASX-MAR) ex-works ₹220-340/kg at 5 MT batch.
Stern tube grease is for the propeller shaft seal area — must be water-resistant, biodegradable (some ports require EAL / VGP compliance), often soft (NLGI 0-1) for stern tube glands. Treat rate ~6-8% biodegradable ester base. Deck grease is general deck-equipment lube — winch, windlass, anchor — robust NLGI 2 CaSX or Al complex with high salt-spray resistance.
Different formulations. EAL (Environmentally Acceptable Lubricants) stern tube grease uses ester base (RAPSOL, PRIOLUBE) and biodegradable additives — premium ₹450-780 / kg.
Share your application (stern tube / deck winch / anchor / boat trailer), EAL requirement, volume and pack format. We respond within one business day with the BOM and ex-works cost.