Product/service fluid

kind differentiated a true kind

service fluid

also called lubricant or functional fluid · operating fluid

A formulated substance charged into a machine to work inside it — an engine oil, a gearbox oil, an automatic-transmission fluid, a hydraulic oil, a brake fluid, an engine coolant, a grease. It is the pool's FIRST SUBSTANCE family: every class minted before it is a made artefact with a shape, and this one is a chemical sold by the litre or the kilogram in a vessel that is not the good. It hangs directly off Product. GREASE IS INSIDE IT, deliberately: a grease is a base oil held in a soap structure, it is graded on the same thickness axis, and its NLGI 000 and 00 grades are semi-fluid — it is a thickened service fluid, not a different kind of thing, and it earns a child class here on two questions no liquid can answer. THE FILL IS `net_content` (contents as sold, over VolumeUnits) for a liquid and `net_weight` for a grease — the 1 L, 4 L and 5 L packs of one oil are versions of one product, which is what net_content's own definition already says about the same drink in several sizes. It is emphatically NOT `capacity`: capacity is the holding volume of an EMPTY durable vessel (b104/b107), and confusing the two would re-open b152. The bottle is PACKING and no container kind is minted for it. It earns its place over Product by NINE slots no other product carries: `fluid_duty` (what job it does in the machine — the fact that makes it what it is, and many-valued because TotalEnergies publishes Rubia SX 40 for hydraulic circuits, engines AND gearboxes at once), `viscosity_grade` with its `grading_scale` (20W-50 on SAE J300, 80W-90 on SAE J306, NLGI 2, ISO VG 46 — the trade's own thickness scales), `meets_specification` with its `specification_scheme` (API SN/CF, ACEA A3/B4, FMVSS 116 DOT 4, DEXRON III, Type WS, NS-3 — the open library of performance documents), `base_fluid` (mineral, semi-synthetic, full synthetic, glycol, silicone — many-valued, because Liqui Moly publishes one brake fluid as both synthetic AND glycol-ether based), `kinematic_viscosity` and `dynamic_viscosity`, each with its `reference_temperature` (mm2/s and mPa·s are different dimensions and are not interconvertible without a density the pool does not hold; the cP figure is the one SAE J300 uses to DEFINE a winter grade), `pour_point`, `boiling_point` with its `fluid_condition`, and `sulphated_ash`. TWO OF THOSE NINE ARE ANSWERABLE ON ONLY PART OF THE FAMILY, and it is recorded rather than hidden: no coolant and no brake fluid publishes a `pour_point` or any `viscosity_grade`, and `sulphated_ash` belongs to crankcase and gear oils. That is the price of correctly folding engine oil, gear oil and hydraulic oil into duty values instead of minting classes for them, and the pool already tolerates it elsewhere (`diameter` on a rectangular box, b153's `thread_size` on a cabin filter). The trigger for revisiting it is written down: if a THIRD liquid-lubricant-only slot appears — total base number is the likely one — a `Lubricant` class under ServiceFluid strictly refines, all three re-home to it under L5, and Grease moves beneath it. Its brand, its maker, the maker's part number, its colour (a coolant's dye and an ATF's red are published characteristics — Coolelf prints 'PINK TO FLUORESCENT ORANGE' in its characteristics table and Toyota Type WS prints 'Red Clear'), its fill, its country of origin and the whole dangerous-goods bundle are already on the universal card and are NOT re-minted: `brand`, `manufacturer`, `trade_identifier` with `identifier_scheme`, `also_known_as`, `color`, `net_content`, `net_weight`, `country_of_origin`, `hazard_class`, `un_number`, `flash_point`, `warning`. In particular `flash_point` is REUSED, not re-minted, although every lubricant sheet publishes it as a plain performance characteristic rather than a shipping fact. WHICH ENGINE OR CAR IT IS FOR IS NOT A POOL FACT and is not stated here (REFINE-LOG 2026-08-25) — but the SPECIFICATION a fluid meets IS a fact about the fluid, and that is where the line falls: 'meets Nissan CVT NS-2' is a property of the oil, 'fits a Nissan Note' is a cross-reference to a product the pool does not hold. It is not an automotive good: UNSPSC files the family in segment 15 (fuels and lubricants), and the industrial hydraulic oil and the bearing grease in this class are the proof.

the reading

A genuine kind — it answers questions its parent does not.

A service fluid is a product that adds its own boiling point, pour point, dynamic viscosity, kinematic viscosity, sulphated ash, base fluid, fluid duty, viscosity grade and meets specification.

what it can tell you the questions a service fluid answers

Grouped by the part of the product each question is about. Every service fluid can answer all of these.

Identity who and what it is

Each service fluid has an also known as, a display name, a meets specification, a model name, a trade identifier, a single active state, a single brand, one or more fluid duties, a single identifier exists, a single manufacturer, a single seller type, a single sub-brand and any number of tracking markings. Each meets specification carries its own specification scheme. Each trade identifier carries its own identifier scheme.

Measurement its measurable, physical facts

Beyond what a product measures, it adds its own pour point (in °C) and sulphated ash. It also records depth, diameter, height, length and width (in millimeters or inches), net content (in liters) and net weight (in grams or kilograms). It can record more than one boiling point, dynamic viscosity and kinematic viscosity. It has a single viscosity grade. Each boiling point carries its own condition measured in. Each dynamic viscosity carries its own reference temperature. Each kinematic viscosity carries its own reference temperature. Each viscosity grade carries its own grading scale.

Facet

It has a single size system. It comes in any number of colors and materials. It offers any number of base fluids, patterns and sizes.

Pricing what it costs

It can be listed at any number of list prices, list prices, list prices, list prices, list prices and list prices. It has a single custom amount enabled. It offers any number of offered bies. Each list price carries its own price valid from, price valid until and price basis. Each offered by carries its own stance and party name. Each price component carries its own price component type and applies to payment method. Each sale price carries its own compare-at price, reference price type, promotion type, price valid from, price valid until, price eligibility and price basis. Each tier price carries its own tiers mode, tier minimum quantity, tier flat fee, price eligibility, price valid from, price valid until and price basis.

Compliance where it is from and what it meets

Each service fluid states its age restriction, country of origin, regulatory permit, responsible person, un number and warning. It may carry any number of certifications, geographical indications and hazard classes. Each geographical indication carries its own designated region. Each hazard class carries its own ghs pictogram and ghs signal word. Each regulatory permit carries its own permit regime. Each warning carries its own warning category.

Media how it is shown

It records description and media. Each media carries its own medium type, media role, media alt text, media facing and document type.

Availability whether it can be obtained

It has a single availability status, any number of eligible regions, any number of ineligible regions and inventory quantity. Each inventory quantity carries its own quantity state, place name and place type.

Social proof what buyers and critics say about it

A service fluid can carry a single fit verdict and aggregate rating, and any number of comments, community answers, community questions, reviews, review highlight tags and engagement counters. Each aggregate rating carries its own rating count. Each comment carries its own commenter name, commenter role and comment date. Each community answer carries its own answerer role, answer accepted and answer vote count. Each community question carries its own question author, question date and question vote count. Each engagement counter carries its own engagement signal, engagement window and engagement rank category. Each review carries its own review rating, review headline, review author, review date, verified purchase, review kind, review aspect, incentive disclosure, review language, review source platform, reviewer media, helpful vote count and variant reviewed.

Condition the state the item is sold in

Each service fluid is sold in a stated item condition. A free-text condition note can add the specifics.

Fulfilment

It measures shipping weight (in grams or kilograms). It has a single requires shipping. It offers any number of fulfilment channels and shipping restrictions. It records hs tariff code. Each shipping rate carries its own delivery speed, shipping region, minimum handling time, maximum handling time, minimum transit time, maximum transit time and free-shipping threshold.

Subscription & financing

Each instalment plan carries its own instalment count, down-payment amount and credit type. Each recurring price carries its own billing interval, interval count, usage type, meter event name, usage aggregation, trial length, trial end behaviour, setup fee, phase iterations and price basis.

Tax

It has a single tax behaviour. It records tax category.

Digital delivery

It has a single gift card. It supports any number of digital delivery methods. Each digital delivery method carries its own licence term, licence scope, delivery platform / drm, download limit and access expiry.

Warranty & returns

It has a single return policy. It records warranty. Each return policy carries its own return window, return method and return fee responsibility. Each warranty carries its own warranty scope and warranty term.

Payment

It supports any number of accepted payment methods.

Eligibility

It measures maximum order quantity and minimum order quantity (as a whole count of selling units). It offers any number of customer eligibilities and purchase gates.

Personalization

It records personalization field. Each personalization field carries its own input type, field required and maximum length.

slot-profile what a service fluid answers

Every question it can answer — added here, shadowed (tightened from a parent), or inherited from above. Each answer is a ◇token, a №number + unit, or “free text.