Neometrix / Service Equipment / Fire Extinguisher Test & Recharge Line / NMX-FES-86

NMX-FES-86 · ENGINEERED-TO-ORDER CLASS — STRIP · TEST · DRY · FILL · CHARGE · CHECK

Fire Extinguisher Test & Recharge Line. Test it wet; fill it dry.

Name: Fire Extinguisher Test and Recharge Line
Brand: Neometrix
SKU: NMX-FES-86

A fire extinguisher test and recharge line takes a portable extinguisher back from the field and returns it proved, filled to its mark and charged to its pressure. Neometrix engineers it as a set of stations: a guarded water test cell, a drying station, a weighed filling station, a dry nitrogen charging panel, a leak check and a weigh-and-tag bench.

So the line has to prove the cylinder with water, get every drop out, and fill and charge it by weight and by gauge.

Discuss a test and recharge line Capability note (PDF)

A guarded test cell for fire extinguisher cylinders on a plain white studio background: a pale grey steel cabinet with a clear guard door, a grey cylinder with a lever head standing on a steel plate inside it and joined by a braided stainless hose to a manifold, with a stainless test pump, a finned motor and a small white water reservoir beside it inside the cabinet, and no people

Fig · 01 — A guarded water test cell: a steel cabinet with a clear guard door, a cylinder inside joined by a braided hose to a manifold, and the test pump and water reservoir beside it — illustrative render.

The result

a proved, dry-filled extinguisherand a record for each unit

The test

with water, in a guarded cellthe cylinder bled of air first

The fill

by weight, to the markdust drawn away from the operator

The charge

dry nitrogen, regulateda relief valve against overcharge

Status

engineered to orderno delivered line claimed

ISO 9001ISO 14001NFPA 10 reference standard

Overview

Why the water test is the easy part, and the drying decides the fill.

Because every extinguisher that is tested with water is full of water afterwards, and the agent that goes in next cannot tolerate any of it.

A filling station for fire extinguisher cylinders on a plain white studio background: a flat pale grey platform scale with a red cylinder standing on it, a stainless funnel in the cylinder neck, a stainless extraction hood on a slim arm with a wide flexible hose curving to a pale grey extraction cabinet, a plain blank indicator box on a column, and no people

Fig · 02 — A filling station: a scale under the cylinder, a funnel in its neck and a hood that draws the dust away — illustrative render.

Test it wet; fill it dry.

What the line is for

It checks, refills and recharges portable extinguishers in numbers: stored-pressure dry chemical units and carbon dioxide units, each with its own record. It takes a unit that has come back from the field and returns one that is proved, filled to its mark and charged to its pressure.

Why the test is done with water

Water hardly compresses. A cylinder that gives way under water pressure lets out very little energy, because there is no stored gas behind it. One that gives way under gas pressure does not. So the cylinder is filled with water, the air is bled out, and the pressure is raised in a guarded cell. The cell is there for the day a cylinder fails.

Why the cylinder is dried

A water test leaves water behind. The dry chemical agent is a fine, dry solid, and moisture makes it lump and discharge badly. So the water is drained, the cylinder is dried right through with warm dry air, and the agent is added only when the cylinder is dry.

Why the fill is by weight

A loose solid settles, so its volume is a poor guide. The agent is weighed in through a funnel to the mass marked on the unit, with the dust drawn away from the operator. A carbon dioxide unit is filled by mass too. Its pressure follows the temperature, so a gauge cannot say how full it is.

Why the charge is dry nitrogen

A stored-pressure unit holds its agent and its gas in one cylinder. The gas is dry nitrogen, because compressed air carries moisture back into the agent. A regulator sets the pressure marked on the unit, and a relief valve stops the cylinder being overcharged. The marked pressure belongs to a stated temperature, so the panel is read with the room in mind.

Why the leak check and the weighing come last

A unit that leaks loses its charge in service, and nobody finds out until it is needed. So each unit goes into a water bath or is wetted with leak-detection fluid, is weighed again against its mark, and is tagged with the date of the test.

The method

Strip, test, dry, fill, charge, and check.

Six steps in a fixed order. The drying and the weighing are the two that a quick job skips.

1 · Strip

The pressure is let out safely at a relief point before anything is unscrewed. The head comes off, and the old agent is emptied out and kept by type.

2 · Test

The cylinder is filled with water, bled of air and pressurised through a test pump inside a guarded cell. The pressure is held and watched, then released.

3 · Dry

The water is drained and the cylinder is dried right through with warm dry air. It is checked, not assumed, before it moves on.

4 · Fill

The agent is weighed in on a scale through a funnel, to the mass marked on the unit, with the dust drawn away.

5 · Charge

Dry nitrogen is set through a regulator to the marked pressure, with a relief valve that stops an overcharge.

6 · Check

A leak check, a final weighing and a tag with the test date. The record for the unit is kept.

Which unit, which way to fill it

Unit	How it is filled	What to watch
Stored-pressure dry chemical (this page)	tested, dried, then the agent is weighed in and dry nitrogen is charged to the marked pressure	the cylinder must be dry before the agent goes in, and the pressure is read with the temperature in mind
Carbon dioxide	the liquid is filled by mass at a charging point after the test	weigh it; the pressure follows the temperature, so a gauge cannot say how full it is, and an overfill is a hazard
Water and foam types	tested in the same cell, then filled and charged on a station set up for the agent	each follows its maker's instructions; the cell and the weighing are shared

The step people underrate is the drying. A cylinder that looks empty can still hold water, and the water only shows up later, in the agent.

Work content

What the line contains, element by element.

Read it as a checklist: a line missing a row will refill extinguishers, but not ones you can trust.

A nitrogen charging panel for fire extinguishers on a plain white studio background: an upright pale grey panel carrying a regulator with a handwheel, a relief valve, ball valves and a manifold joined by stainless tubing, a black hose curving to a red extinguisher cylinder with a lever head, and a dark grey gas cylinder behind the panel joined by a braided hose, and no people

Fig · 03 — A charging panel: a regulator and a relief valve on a plain panel, a hose to the extinguisher, and a nitrogen cylinder behind — illustrative render.

Element	What it does	What matters
Receiving point	lets the pressure out and removes the head	a safe release point, so nothing is unscrewed while the cylinder is still under pressure
Emptying point	takes the old agent out	the agent is kept by type, so one kind never ends up in a unit made for another
Guarded test cell	holds the cylinder while it is tested	a strong guard with a door that is interlocked, because it must stand up to the day a cylinder fails
Water circuit and test pump	fill the cylinder and raise the pressure	the air is bled out first, with a relief valve, a gauge and isolating valves, so the pressure can be held and watched
Drain and drying station	get every drop out	warm dry air through the cylinder, and a check that it is dry before it moves on
Filling station	puts the agent in by weight	a scale, a funnel and dust extraction, with one agent type at a time
Charging panel	sets the gas pressure	dry nitrogen through a regulator, a relief valve against overcharge, and an adaptor for each valve type
Leak check	shows a slow leak	a water bath or leak-detection fluid, looked at with the cylinder still under its charge
Weigh-and-tag bench	confirms the fill and marks the unit	a final weighing against the mark, and a tag with the date of the test
Carbon dioxide charging point	fills those units by mass	weighed as it is filled, with the pressure left to follow the temperature
Procedure and record	fix the sequence and keep the evidence	strip, test, dry, fill, charge and check, the same for every unit, with one record for each
Testing & documentation	prove the line first	the cell tried with a known cylinder, the interlocks exercised, the scale checked, and a record the customer can inspect

The elements that decide the result are the drying station and the weighing, and the one that decides whether it stays safe is the guarded cell. The first two keep the agent dry and the fill right, and the third keeps the person at the bench safe.

Full specification — expand

System	A receiving point where the pressure is let out safely and the head is removed; an emptying point for the old agent, kept by type; a guarded test cell with a water circuit, a test pump, a relief valve and a gauge; a drain and drying station with warm dry air; a filling station with a scale, a funnel and dust extraction; a charging panel with dry nitrogen, a regulator and a relief valve; a leak check in a water bath or with leak-detection fluid; a weigh-and-tag bench; a written procedure; a record for each unit; and testing and documentation before handover
The One Idea	Test it wet; fill it dry.
Why The Test Is Done With Water	Water hardly compresses, so a cylinder that gives way under water pressure lets out very little energy, while one that gives way under gas pressure does not; the cylinder is therefore filled with water, bled of air and pressurised in a guarded cell
Why The Cylinder Is Dried	A water test leaves water behind, and moisture makes the dry chemical agent lump and discharge badly, so the water is drained, the cylinder is dried right through with warm dry air and checked, and the agent is added only when it is dry
Why The Fill Is By Weight	A loose solid settles, so its volume is a poor guide; the agent is weighed in to the mass marked on the unit, and a carbon dioxide unit is filled by mass too, because its pressure follows the temperature and a gauge cannot say how full it is
Standards	NFPA 10 covers portable fire extinguishers, including their maintenance and hydrostatic testing; IS 15683 covers their performance and construction and IS 2190 their selection, installation and maintenance. This page prints none of their intervals, pressures, classes or tolerances, and no edition year: those come from the standard the customer names and from the extinguisher maker. Approval of a unit, a line or a workshop rests with the customer and the authority they name; none is claimed here
Configurations	A test and dry station, a fill and charge station, and a complete service line
Scope Boundary	This page is the fire extinguisher test and recharge line, which tests, refills and recharges portable extinguishers. It is not a hydrostatic test bench, which proves large gas cylinders (see hydrostatic test bench), not a gas filling system, which fills gas into cylinders (see carbon dioxide and nitrogen filling system) and not a gas fire suppression system, which is the fixed system in a room (see gas fire suppression system). It does not make or supply extinguishers. No certification, approval or licence is claimed here
Status	Neometrix engineers fire extinguisher test and recharge lines to order, and no delivered fire extinguisher test and recharge line is claimed.

Configurations

One method, three ways to build the line.

The method, the drying check, the weighing and the record are shared. What changes is how many stations the workshop needs and which ones it already has.

Test and dry station

A guarded cell and a drying station, for a workshop that already fills

For a workshop that already refills: the guarded test cell with its water circuit, and the drying station that gets every drop out, with a record for each cylinder.

Fill and charge station

A weighed filling station and a nitrogen panel, for a workshop that already tests

For a workshop that already tests: the filling station with its scale, funnel and dust extraction, the dry nitrogen charging panel, the leak check and the weigh-and-tag bench.

Complete service line

All six steps in a fixed order, with one record for each unit

For a plant or a service workshop that wants the whole sequence, laid out so that a cylinder moves one way and a wet one never goes back past the drying station.

And the part that is not equipment at all, yet decides all three: the procedure and the test plan. They fix the order of the steps, the checks at each, the limits the customer supplies and what is recorded. They are written from the customer's own extinguishers and standard, not from the line.

The drawing

A reference sheet, drawn as a real CAD sheet.

One sheet of one reference configuration: the process and instrument schematic of a test and recharge line. It shows the six stations in order, the water, dry-air, extraction and nitrogen circuits that serve them, and what holds or releases a unit. It carries tags and arrangement only. Every pressure, interval, mass and time is fixed by design for the customer's extinguishers and standard.

Fig · 04 — Sheet 01, the process and instrument schematic: the six stations in order, the water test circuit, the drying check and the nitrogen charge. Reference configuration, tags only.

Every real line is drawn for its own extinguishers, supplies and site. This sheet is the arrangement and the order of release that a project set starts from. Approval of any drawing rests with the customer and the authority they name; none is claimed here.

PDF · one sheet

Reference drawing — process and instrument schematic

PDF · capability sheet

Fire extinguisher test and recharge line — what Neometrix engineers

Where it is used

Wherever portable extinguishers are kept, and have to work on the day.

The common thread is a large number of small units, a duty to keep them ready, and a failure that only shows when someone reaches for one.

Plants and refineries

Where many portable extinguishers are spread across a site and are tested and refilled in house.

Service workshops

Where one bench looks after the extinguishers of many customers, and the record is part of what they pay for.

Campuses, hospitals and large estates

Where the units sit in corridors and plant rooms and have to be there, charged, on the day.

Terminals and logistics sites

Where extinguishers ride on equipment and sit in stores, and come back from the field in batches.

Watch

See it in motion.

A short walkthrough video of the fire extinguisher test & recharge line.

FAQ

Common questions.

Longer answers, for readers who want the reasoning.

Q · 01 What does a fire extinguisher test and recharge line actually do?

It takes a portable extinguisher that has come back from the field and returns it proved, filled and charged. The pressure is let out, the old agent is emptied, the cylinder is tested with water in a guarded cell, drained and dried right through, filled by weight, charged with dry nitrogen to the marked pressure, leak-checked, weighed and tagged. It does not decide how often a unit must be tested: that comes from the standard the customer follows, and the line holds the record.

Q · 02 Why test with water and not with gas?

Because water hardly compresses, so there is almost no stored energy in the cylinder under test. If a cylinder fails under water pressure, it lets out very little energy and the water simply runs out. If one fails under gas pressure, the gas that was squeezed into it expands at once, and the release is far harder. That is why the cylinder is filled with water and the air is bled out first, so that no pocket of gas is left. The guarded cell is still there, because a cylinder can fail, and the person at the bench must not be in the way when it does.

Q · 03 Why must the cylinder be dried before it is filled?

Because the test leaves water in it, and a dry chemical agent is a fine dry solid that lumps in moisture and then discharges badly. A cylinder that looks empty can hold water at its bottom and under its fittings. So the water is drained, warm dry air is passed through the cylinder until the air leaving it is as dry as the air entering it, and the agent is added only then. The same reason is why the gas for the charge is dry nitrogen and not compressed air, which carries moisture with it.

Q · 04 Why fill by weight, and why dry nitrogen with a relief valve?

A loose solid settles and packs, so its volume says little about how much is there, and its mass does. The agent is weighed in through a funnel to the mass marked on the unit, and the whole unit is weighed again at the end. A carbon dioxide unit is filled by mass too, because the pressure of liquid carbon dioxide follows its temperature, so a gauge cannot say how full the unit is. For a stored-pressure unit the gas is dry nitrogen, set through a regulator to the pressure marked on it, with a relief valve so that a fault in the panel cannot overcharge the cylinder. The marked pressure belongs to a stated temperature, so the panel is read with that in mind.

Q · 05 Is this the same as the hydrostatic test bench, the carbon dioxide and nitrogen filling system or the gas fire suppression system?

No, and the differences are worth stating precisely. The hydrostatic test bench page covers proving gas cylinders with water. The carbon dioxide and nitrogen filling system page covers filling those gases into cylinders. The gas fire suppression system page covers the fixed system in a room, and says in its own words that a portable extinguisher is different equipment. This page is the fire extinguisher test and recharge line, for the small portable unit, from strip to tag. It does not replace any of them, and it does not claim what they claim a second time.

Q · 06 Has Neometrix built one of these?

We would rather answer this plainly than let a page imply otherwise. Neometrix engineers fire extinguisher test and recharge lines to order, and no delivered fire extinguisher test and recharge line is claimed. What stands behind the offer is adjacent: Neometrix engineers a hydrostatic test bench (see the hydrostatic test bench page), a carbon dioxide and nitrogen filling system (see the carbon dioxide and nitrogen filling system page) and a gas fire suppression system (see the gas fire suppression system page). The test pump, valves, gauges, scale, dust extractor and nitrogen supply are catalogue items, bought in, not invented. What Neometrix engineers is the line around them: the guarded cell and its water circuit, the drying station, the filling station, the charging panel, the leak check, the weigh-and-tag bench, the procedure and the record. So the honest position is that the line is engineered to order, the neighbouring disciplines are in the building, and the first line of this exact kind will be built around the customer's own extinguishers rather than taken off a shelf.

Q · 07 Which standards apply, and what can the line not do?

NFPA 10 covers portable fire extinguishers, including their maintenance and hydrostatic testing. IS 15683 covers their performance and construction, and IS 2190 their selection, installation and maintenance. This page prints none of their intervals, pressures, classes or tolerances, and no edition year: those come from the standard the customer names and from the extinguisher maker. The line tests, refills and recharges. It does not make or supply extinguishers, it does not decide how often a unit is tested, and it does not replace a maker's instructions: this page claims no certification, approval or licence. No pressure, interval, mass, time, size or quantity figure is printed here, and approval for use rests with the customer and the authority they name; none is claimed here.

Q · 08 What do you need from us to quote?

Six things, and most of them describe your extinguishers rather than the line. First, the units: the types you handle (stored-pressure dry chemical, carbon dioxide, water or foam) and the range of cylinder sizes. Second, the throughput: how many units come through, and whether they arrive in batches. Third, the test: the pressure and the interval your standard sets, which you supply. Fourth, the agent and the gas: what you fill and how the nitrogen is supplied. Fifth, the site: the floor, the water and electrical supply and the extraction. Sixth, the record: what you want kept for each unit. From that we come back with a line concept, a written test plan you can check, and a budgetary price.

The neighbouring pages, and how they differ from this one.

Three neighbours: one proves gas cylinders, one fills gases, one is the fixed system in a room.

↗ Cylinder testing

Hydrostatic Test Bench

Proves gas cylinders with water - the same principle, where this page covers the small portable extinguisher and what goes in after the test.

↗ Gases

Carbon Dioxide and Nitrogen Filling System

Fills carbon dioxide and nitrogen into cylinders - a gas filling system, where this page tests, fills and charges a complete extinguisher.

↗ Fixed systems

Gas Fire Suppression System

The fixed system that holds the gas in a room - a different kind of equipment from the portable unit this page looks after.

Browse all Neometrix product lines.

Get a quotation

Tell us the extinguishers,
and how many come through.

The projects desk replies within two working days with a line concept, a written test plan you can check, and a budgetary quotation. Write to [email protected] or use the form.

Enquire — test and recharge line Capability sheet (PDF) +91 7777 876 876

ISO 9001 / 14001 ENGINEERED-TO-ORDER CLASS — FIRE EXTINGUISHER TEST & RECHARGE LINE STRIP · TEST · DRY · FILL · CHARGE · CHECK — TEST IT WET; FILL IT DRY ENGINEERED IN NOIDA · INDIA