Sodium soap grease is legacy fibrous-structure grease using Na 12-hydroxystearate as thickener. Distinguished by stringy / thread-like texture, drop 175-185 °C, and unique water-EMULSIFYING property (opposite of lithium's water-resistance). Historically dominant in water pump bearings; now niche legacy + select water-emulsion applications. India market ~500-1,500 MT/year (declining vs lithium). This guide gives the BOM and the critical controlled-cooling process discipline.
| Component | Function | % (m/m) | Indian Supplier |
|---|---|---|---|
| Group I SN500 base oil | Carrier base oil | 76.0% | IOCL / HPCL Group I |
| 12-Hydroxystearic acid (or stearic acid) | Soap-forming fatty acid | 9.0% | Croda / Godrej / Wilmar India |
| Sodium hydroxide (NaOH) | Alkali for saponification | 1.5% | Indian inorganic suppliers |
| Mixed ZDDP AW (low treat) | Anti-wear | 0.8% | Lubrizol / Lubechem LC-AW-ZDDP |
| 2,6-DTBP phenolic AO | Oxidation inhibitor | 0.4% | BASF Irganox |
| Alkenyl-succinic-acid CI | Ferrous rust inhibitor | 0.4% | King K-Corr 200 |
| PIB tackifier (Mn 1300) | Adhesion | 0.5% | BASF Glissopal |
| Mineral oil flash-off | Mixing carrier — partially flashes | 5.0% | IOCL Group I 150N |
| Yellow / amber dye | Traditional Na grease colour | 100 ppm | Clariant pigments |
| Group I 150N diluent | Consistency fine-tune | 6.4% | IOCL Group I |
| TOTAL | 100.0% | — | |
Process: saponify fatty acid + NaOH slurry (NaOH in 5-8% warm water) in base oil at 195-215 °C; CRITICAL — controlled slow cool at 1-2 °C/min through 90-120 °C window for fibrous crystal habit (fast cool destroys structure); add additives below 100 °C; GENTLE single-pass mill (high-shear mill breaks fibres). QC: drop 175-185 °C, penetration 265-295, working stability NLGI 2 → 3-4 after working (less stable than lithium). Ex-works ₹95-145 / kg at 5 MT batch — competitive with EP2 lithium for cost-sensitive niche customers. The AW and rust chemistry draws on our grease additive package range; batch QC follows our ASTM lubricant & grease testing protocols, and the slow-cool kettle is costed in our grease plant setup cost guide.
Sodium soap grease is legacy grease using sodium 12-hydroxystearate as thickener. Distinguished by fibrous structure (long needle-like soap fibres giving 'stringy' or 'thread-like' grease texture), drop point 175-185 °C, and unique water-EMULSIFYING property — Na soap grease emulsifies water rather than rejecting it.
Used historically in water pump bearings, older industrial ball bearings, low-temperature transmission grease. Largely replaced by lithium grease since 1950s due to lithium's superior water-resistance + dropping point. Still in service for select legacy applications and as low-cost industrial grease in some markets. For higher-temperature replacements, see our lithium complex grease manufacturing and polyurea grease manufacturing routes.
Sodium soap grease NLGI 2 BOM (%): Group I SN500 76%, 12-HSA (or stearic acid) 9%, NaOH 1.5%, ZDDP 0.8%, phenolic AO 0.4%, ASA CI 0.4%, PIB tackifier 0.5%, mineral oil flash-off 5%, yellow/amber dye 100 ppm, balance Group I diluent.
Process: saponify at 195-215 °C; controlled slow cool at 1-2 °C/min for fibrous crystal habit; add additives below 100 °C; gentle single-pass mill. Drop 175-185 °C, penetration 265-295.
Sodium 12-hydroxystearate soap is hydrophilic — the sodium ion has high affinity for water. When water contacts Na grease, the soap partially dissolves and forms water-in-oil emulsion that retains lubricant film. OPPOSITE of lithium (Li 12-OH) soap which is hydrophobic and rejects water.
Historically valued in water pump bearings — small water leakage absorbed into grease without immediate lubrication loss. Modern water pumps use sealed-for-life lithium complex or polyurea — sodium grease application now niche / legacy only.
(1) Legacy industrial maintenance — older ball bearings with established Na grease spec. (2) Some marine boat hull bearings + propeller stuffing box — water emulsifying preferred. (3) Some textile spinning frame bearings — vintage equipment. (4) Very-low-temperature applications below -20 °C where lithium becomes too stiff.
Indian total Na grease volume small ~500-1,500 MT/year (declining) vs lithium grease ~50,000+ MT/year. Niche supplier opportunity rather than mainstream. Producers serving these niches usually also run non-soap lines such as bentonite clay grease manufacturing and high-temperature barium complex grease manufacturing to broaden their catalogue.
Indian Na soap grease suppliers (small volume): IOCL Servo Sodium Grease, BPCL Mak Sodium Grease, HPCL Sodium Grease — legacy SKUs. Most large blenders deprioritised Na over 2000-2020 as lithium volume grew. Small Indian private-label aftermarket suppliers still produce Na grease for textile, vintage industrial.
Pricing ₹120-200 / kg retail (cheaper than EP2 lithium ₹150-250 / kg). Lubechem custom (LC-GR-NA-NLGI2) ex-works ₹95-145 / kg at 5 MT batch. Many of these blenders also diversify into adjacent chemistry such as DEF / AdBlue manufacturing to use spare plant capacity.
The technical hurdle in Na grease is producing the characteristic fibrous soap structure. Critical process parameter is COOLING RATE after saponification — 1-2 °C/min controlled cool required. Fast cool (>5 °C/min) destroys fibrous structure, giving granular soap with poor body. Slow cool (<0.5 °C/min) gives over-fibrous grease that's too stringy.
Milling must be gentle — high-shear mill breaks fibres. Indian Na grease producers use jacketed slow-cool kettle + single-pass roller mill instead of high-shear colloid mill used for lithium. Process discipline distinguishes good vs poor Na grease.
Share your legacy application + spec match requirement and volume. We respond within one business day with the BOM and ex-works cost.