High-temperature (HT) grease is engineered for continuous service above 150 °C — typically 180-220 °C with brief peaks to 260-280 °C — in kiln bearings, furnace fan bearings, oven chains, drying chamber rollers and rotary kiln support rollers. Required: dropping point >280 °C, oxidation life D942 <10 kPa @ 100 hr, synthetic base oil (PAO / ester). This guide gives the recommended calcium sulfonate complex BOM (the sweet spot for Indian industrial HT), thickener selection by temperature window, Indian applications and brand benchmarks.
| Component | Function | % (m/m) | Indian Supplier |
|---|---|---|---|
| PAO 6 cSt base oil | Synthetic base, KV100 ~6 cSt, thermal stability | 55.0% | INEOS Durasyn / ExxonMobil SpectraSyn |
| Overbased Ca sulfonate TBN 400 | Gellant precursor + reserve alkalinity | 25.0% | Lubrizol 6477 / OLOA 4900-B / Lubechem LC-DTR-CASULF-400 |
| Calcium hydroxide (lime) | Complexing alkali | 1.5% | Indian inorganic suppliers |
| 12-Hydroxystearic acid | Complexing fatty acid | 4.0% | Croda / Godrej / Wilmar India |
| Boric acid | CaSX gel-structure complexing | 0.5% | Indian boron chemistry suppliers |
| Sulphurised olefin EP | Extreme pressure | 2.0% | Lubrizol Anglamol 99 |
| Mixed ZDDP AW | Anti-wear, secondary AO | 1.0% | Lubrizol / Afton |
| Methylene-bis-DTBP phenolic AO | Low-volatility primary AO | 1.0% | Albemarle Ethanox 4710 |
| Alkylated DPA aminic AO | High-temp secondary AO | 1.0% | LANXESS Naugalube 438L |
| Calcium nitrite CI | Vapour-phase rust inhibitor | 0.8% | Indian inorganic |
| PIB tackifier (Mn 1300) | Adhesion + cohesion | 0.7% | BASF Glissopal |
| PAO 8 cSt diluent | Consistency fine-tune | 8.4% | INEOS Durasyn |
| Brown dye | HT grease identification | 100 ppm | Clariant pigments |
| TOTAL | 100.0% | — | |
Process: pre-gel CaSX with 4-5% water at 80-95 °C; add 12-HSA + Ca(OH)2 + boric acid for complexing at 95-110 °C; in-situ complexing 110-140 °C; dehydration vacuum 140 °C; cool to 90 °C and add EP/AW/AO/CI/tackifier; mill to NLGI 2. Final QC: drop no-drop (>300 °C), penetration 270-285, 4-ball weld 400+ kgf, D942 oxidation <5 kPa @ 100 hr, D2266 wear <0.45 mm. Ex-works cost ₹360-520 / kg at 5 MT batch.
| Property | Test Method | HT Spec | LC-GR-CASX-HT Target |
|---|---|---|---|
| Worked Penetration | ASTM D217 | 265-295 | 270-285 |
| Dropping Point | ASTM D2265 | >280 °C | No drop / >300 °C |
| Oxidation Stability @ 100 hr / 99 °C | ASTM D942 | <15 kPa | <5 kPa |
| Oxidation Stability @ 500 hr | ASTM D942 | <40 kPa | <15 kPa |
| 4-Ball Weld Load | ASTM D2596 | 315 kgf min | 400+ kgf |
| 4-Ball Wear Scar | ASTM D2266 | <0.55 mm | <0.45 mm |
| Water Washout @ 79 °C | ASTM D1264 | <10% | <5% |
| Copper Strip @ 121 °C / 24 hr | ASTM D4048 | 1B | 1A-1B |
| Roll Stability @ 80 °C, 200k cycles | ASTM D1831 | <15% | <10% |
High temperature (HT) grease is grease designed for continuous service above 150 °C — typically 180-220 °C continuous with peaks to 260-280 °C. Used in kiln bearings (cement, ceramic, brick), furnace fan bearings (steel, glass), oven chain (paint shop, food bakery), drying chamber rollers, rotary kiln support roller.
Requires dropping point >280 °C and oxidation life >500 hr at 150 °C. Standard thickeners: calcium sulfonate complex (drop >300 °C), polyurea (drop >260 °C), lithium complex (drop >260 °C). Base oil PAO, ester or high-VI Group III for thermal stability.
NLGI 2 calcium sulfonate complex HT grease BOM (%): PAO 6 cSt base oil 55%, overbased calcium sulfonate TBN 400 (gellant) 25%, calcium hydroxide 1.5%, 12-hydroxystearic acid 4%, boric acid 0.5%, sulphurised olefin EP 2%, ZDDP AW 1%, phenolic AO methylene-bis-DTBP 1%, aminic AO alkylated DPA 1%, calcium nitrite CI 0.8%, PIB tackifier 0.7%, dye 100 ppm, balance PAO 8 cSt diluent.
Process: pre-gelation with water + sulfonate at 80-95 °C; in-situ complexing with Ca(OH)2 + 12-HSA + boric acid; finishing 140 °C; milling. Drop no-drop (>300 °C), penetration 270-285, 4-ball weld 400+ kgf, D942 oxidation <5 kPa @ 100 hr.
For continuous service 150-180 °C: lithium complex (drop >260 °C, cheapest HT option). For 180-200 °C: calcium sulfonate complex (drop >300 °C, inherent EP + corrosion). For 200-220 °C: polyurea (excellent oxidation, sealed-for-life). For >220 °C: bentonite organoclay (no soap melt) or PFPE for extreme.
Cost ranking: Li complex < CaSX < polyurea < bentonite < PFPE. For most Indian industrial HT applications (kiln, oven, furnace fan), CaSX is the sweet spot — performance, cost and BIS-acceptable.
Mineral base oil oxidises rapidly above 150 °C — RPVOT drops, oil bleeds and darkens, viscosity rises by varnish formation. Group I SN500 is unsuitable for sustained 180+ °C service. Group II 220N is marginal. Synthetic base oils — PAO (polyalphaolefin, drop pour <-50 °C, thermal stability 250+ °C), ester (POE, TMP-trioleate), or polyglycol PAG — are standard for HT grease.
PAO is the universal choice; ester is used when additive solubility matters or for food-grade. PAO costs ₹220-340/kg vs Group I SN500 at ₹80-110/kg — the HT grease premium is driven mostly by base oil choice.
Indian HT grease volume: cement plant kiln and pre-heater (Ambuja, UltraTech, ACC, Dalmia), steel plant furnace fan bearings (Tata Steel, JSW, Sail), glass plant feeder bearings (Saint-Gobain), brick kiln drying chamber, ceramic / sanitary kiln, food industry oven chain, automotive paint shop oven, textile drying.
Brands: SKF LGHB 2 (sulfonate complex 200 °C), Mobil Polyrex EM (polyurea 200 °C), Klüber Petamo GHY 133 N (synthetic 160 °C), IOCL Servo Hytemp, BPCL Mak Heat Resist. ₹400-1,200 / kg depending on chemistry. Lubechem custom CaSX HT (LC-GR-CASX-HT) ex-works ₹360-520/kg.
ASTM D942 (oxidation bomb stability) — grease in O2-pressurised bomb at 99 °C, oxygen pressure drop measured at 100 hr and 500 hr. Standard EP2 lithium grease drops 20-40 kPa at 100 hr; HT grease must drop <10 kPa at 100 hr and <40 kPa at 500 hr.
Achieved by synthetic base oil (PAO / ester) plus heavy AO loading (phenolic 0.8-1.5% + aminic 0.5-1.0%). Some OEM HT specs require RPVOT D2272 >1,000 minutes on extracted base oil — only synthetic bases can pass.
Share your service temperature window, application (kiln / furnace / oven / paint shop / food), volume and budget. We respond within one business day with thickener selection, BOM and ex-works cost.