Industrial Glossary — Lubricants, Welding, Fire Protection, Surge Protection, Standards
This glossary defines the industrial terms most-frequently used by maintenance engineers, procurement leads, fabricators, electrical engineers, and fire-safety officers across the categories Vasundhara Performance Solutions supplies — industrial lubricants and metalworking fluids, welding consumables, fire protection equipment, surge protection devices, and the international standards governing them.
Each term is paired with a concise technical definition calibrated to Indian industrial practice and the Indian Standards / IEC / ISO / NFPA / AWS / DIN frameworks most commonly referenced in procurement specifications and code-compliant work.
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Lubricants (12) Welding (5) Fire Protection (5) Surge Protection (4) Standards (4)Lubricants
ISO VG
ISO 3448 viscosity grade — classifies lubricants by kinematic viscosity at 40°C in centistokes (cSt). ISO VG 32 = 28.8-35.2 cSt; VG 46 = 41.4-50.6 cSt; VG 68 = 61.2-74.8 cSt. The standard reference for industrial lubricant viscosity selection.
NLGI Grade
National Lubricating Grease Institute consistency classification — measures grease firmness from NLGI 000 (semi-fluid) through NLGI 6 (block-hard). NLGI 2 is the standard for most industrial bearing applications; NLGI 0/1 for centralised lubrication systems.
AW (Anti-Wear)
Additive class providing protection under boundary lubrication — typically zinc dialkyl dithiophosphate (ZDDP). Forms a sacrificial film on metal surfaces preventing direct metal contact under load. Standard in industrial hydraulic and gear oils.
EP (Extreme Pressure)
Additive class providing protection under shock loading and high pressure — sulphur-phosphorus or chlorine-based chemistry. Used in industrial gear oils, slideway oils, and metalworking fluids where AW is insufficient. EP grades are essential for FZG load-stage performance.
ZDDP
Zinc Dialkyl Dithiophosphate — the dominant anti-wear and anti-oxidation additive in industrial lubricants. Provides AW film, oxidation protection, and corrosion resistance. Found in all major hydraulic oils, gear oils, and motor oils unless specifically zinc-free.
TAN (Total Acid Number)
ASTM D664 measure of lubricant acidity in mg KOH per gram of oil. Rises as anti-oxidant additives deplete and the base oil oxidises. Doubling of TAN from baseline = drain trigger for industrial gear and hydraulic oils.
TBN (Total Base Number)
ASTM D2896 measure of alkaline reserve in motor and crankcase oils — typically 8-15 mg KOH per gram. TBN neutralises acidic combustion by-products. Drops as the oil ages; replacement triggered when TBN falls below 50% of fresh-oil baseline.
ISO 4406
Cleanliness code for hydraulic and lubricating oils — three numbers separated by slashes representing particle counts at 4, 6, and 14 microns (e.g., 18/16/13). Each number doubles for each step. Industrial hydraulic systems target 18/16/13 or cleaner; servo systems require 17/15/12.
RPVOT
Rotating Pressure Vessel Oxidation Test (ASTM D2272) — measures oxidation resistance of lubricants. Higher RPVOT minutes = longer expected oil life. Premium turbine oils target ≥ 1500 minutes; standard industrial oils ≥ 250 minutes.
NSF H1
NSF International registration for lubricants where incidental food contact is possible — allows up to 10 ppm oil-on-product contamination. Required for food-processing, dairy, pharmaceutical, and beverage equipment lubrication. Examples: SELCO NSF H1 grease, Castrol Optileb.
FZG
DIN 51354 / ISO 14635 gear oil EP test — gear-rig load test reporting the failure-load stage. Industrial gear oils target FZG ≥ 12; premium grades reach stage 14+. Stage 12 is the minimum for most CLP gear oils per DIN 51517 Part 3.
Demulsibility
Lubricant property — how rapidly water separates from oil (ASTM D1401). Critical for hydraulic, turbine, and slideway oils where water contamination is possible. Premium oils separate ≥ 95% in 1 hour; poor demulsibility = persistent emulsion = additive failure.
Welding
AWS A5.1 / A5.5
American Welding Society standards classifying covered electrodes for SMAW (manual metal arc welding). A5.1 covers carbon steel electrodes (E6010, E6013, E7018, etc.); A5.5 covers low-alloy steel electrodes (E8018-B2, E9018-B3 chrome-moly). Universally referenced in WPS and procurement.
SMAW / MMAW
Shielded Metal Arc Welding (US) / Manual Metal Arc Welding (UK) — the most common welding process using flux-coated stick electrodes. Versatile, equipment-simple, and works in all positions. The process for which AWS A5.1 / A5.5 electrodes are designed.
MIG / GMAW
Metal Inert Gas (UK) / Gas Metal Arc Welding (US) — semi-automatic welding using continuous wire electrode and shielding gas. Higher deposition rates than SMAW, better suited for production welding of mild steel, stainless steel, aluminium. Requires shielding-gas supply (Ar/CO2 mix) and wire feed.
TIG / GTAW
Tungsten Inert Gas (UK) / Gas Tungsten Arc Welding (US) — non-consumable tungsten electrode with inert shielding gas (typically argon). Highest-quality welding process, used for thin sheet stainless steel, aluminium, root passes on pipe, aerospace and pharma applications. Slower than MIG but cleaner.
SAW
Submerged Arc Welding — automatic process where the arc is buried under granular flux. Very high deposition rates, used for heavy structural steel fabrication (ship plate, pressure vessel longitudinal seams, structural beams). Limited to flat or horizontal positions.
Fire Protection
IS 13947
Indian Standard for installation and maintenance of internal hydrant systems for buildings — specifies pump capacities, hydrant spacing (max 30 m from any building point), pressure ratings, hose dimensions, and testing protocols. Applies to industrial, commercial, and high-rise buildings in India.
UL Listed
Underwriters Laboratories certification confirming a fire-protection product meets defined performance and safety standards. UL-listed sprinklers, hydrant valves, alarm devices, and fire-resistive systems are required for code-compliant installations in many international standards and risk-rated insurance.
NFPA 13
National Fire Protection Association standard for installation of sprinkler systems — the international benchmark for sprinkler design, hazard classification, water demand, hydraulic calculation, and component specification. Used alongside IS 15105 for international-grade installations in India.
Pre-action Sprinkler
Dry-pipe sprinkler system where pipe network fills with water only after a separate fire detection signal (typically smoke or heat detectors). Used in cold-climate, freezer, archive, and data-centre applications where accidental water discharge would be costly.
Foam Pourer
Discharge device for foam systems protecting flammable-liquid storage tanks — delivers low-expansion foam over the surface of the burning fuel to smother and cool. Designed per IS 12469 / NFPA 11. Used at refinery storage tanks, petroleum bulk terminals, marine fuel depots.
Surge Protection
SPD (Surge Protective Device)
Component installed in electrical distribution to limit transient overvoltages and divert surge current — protects electrical and electronic equipment from lightning and switching transients. Classified Type 1 / Type 2 / Type 3 per IEC 61643 / IS 17131 by waveform and installation point.
Iimp
Impulse current rating for Type 1 SPDs — peak current the device can handle on the 10/350 µs lightning waveform. Typical industrial values: 12.5 kA (low exposure) to 50 kA (high exposure with bonded LPS). Per pole rating; multi-phase SPDs use four poles for TT/TN systems.
In
Nominal discharge current for Type 2 / Type 3 SPDs — peak current the device handles on the 8/20 µs switching waveform. Type 2 typical In = 20 kA per pole; Type 3 typical In = 5-10 kA per pole. Higher In = longer service life under repeated surge stress.
Up
Voltage protection level — the maximum voltage that appears at the SPD terminals during a surge event. Lower Up = better protection. Type 1 typical Up ≤ 2.5 kV; Type 2 ≤ 1.5 kV; Type 3 ≤ 1.0 kV. Up must be below the protected equipment's impulse withstand voltage.
Standards
IP-65 / IP-66 / IP-67
Ingress Protection rating per IEC 60529 — first digit is dust protection (6 = dust-tight), second digit is water protection (5 = water jets; 6 = strong water jets; 7 = temporary submersion). IP-65 is the standard for outdoor industrial enclosures; IP-66 for marine; IP-67 for submersible applications.
ISO 9001
International Organization for Standardization quality management standard — defines requirements for QMS covering design, production, delivery, and customer satisfaction. Standard procurement requirement for industrial supply contracts. Vasundhara Performance Solutions and partner manufacturers are ISO 9001 compliant.
IATF 16949
Automotive industry quality management standard built on ISO 9001 — required for tier-1 and tier-2 suppliers to OEM auto manufacturers. Adds automotive-specific requirements for production process, traceability, and continuous improvement. Industrial lubricants supplied to auto-ancillary plants typically require IATF 16949 documentation.
CE Marking
European Conformity marking confirming a product meets EU health, safety, and environmental requirements. Applies to electrical equipment, machinery, pressure equipment, PPE, and many other categories. Indian manufacturers exporting to Europe require CE certification; CE-marked equipment imported to India is generally preferred for code-compliant projects.
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