Neometrix / Calibration / Force Calibration Machine / NMX-FCM-84

NMX-FCM-84 · ENGINEERED-TO-ORDER CLASS — SPECIFY · FRAME · ALIGN · CONTROL · CALIBRATE · PROVE

Force Calibration Machine. Load it straight; hold it still.

Name: Force Calibration Machine
Brand: Neometrix
SKU: NMX-FCM-84

A force calibration machine loads a force-measuring instrument, a load cell, a proving ring or a force transducer, to known forces and compares what it reads with a reference. Neometrix engineers it as a comparison machine: a rigid frame, a hydraulic actuator, and a reference transducer in the same load line as the instrument.

So the machine has to load the instrument straight, hold the force still while it is read, and know its own reference.

Discuss a force calibration machine Capability note (PDF)

A force calibration machine on a plain white studio background: a pale grey steel loading frame with a flat base plate, two square columns and a crosshead, a bright steel hydraulic cylinder at the centre of the base pushing a ram up to a round lower platen, above it a stack of two plain cylindrical stainless force transducers joined by ball-shaped spherical seats to a round upper platen under the crosshead, a clear guard panel in front of the stack, and a small pale grey hydraulic power unit with a motor and a valve block joined to the cylinder by two black hoses, and no people

Fig · 01 — A force calibration machine: a rigid loading frame with a hydraulic actuator at its base, a load train between two platens, a guard, and a hydraulic power unit beside it — illustrative render.

The result

a record for every instrumentforces, readings, positions and differences

The load

along one straight lineframe, platens and spherical seats

The hold

steady while it is readfine control of the actuator

The reference

a transducer with its own recordtraced to a higher standard

Status

engineered to orderno delivered machine claimed

ISO 9001ISO 14001ISO 376 · ASTM E74 reference standards

Overview

Why a calibration is only as good as the line the force travels.

Because a force instrument reads well only when it is loaded the way it was made to be loaded, and a comparison is fair only when the force stands still while both instruments are read.

A force calibration load train on a plain white studio background: from the bottom up a round stainless lower platen with a shallow central seat on a small pale grey base block, a ball-shaped spherical seat, a plain cylindrical stainless force transducer with a short black cable, a second spherical seat, a second cylindrical force transducer with its own cable, a third spherical seat and a round upper platen, all on one vertical line, and no people

Fig · 02 — One load train: a lower platen, a reference transducer, an instrument under calibration and an upper platen, each joined by a spherical seat, all on one vertical line — illustrative render.

Load it straight; hold it still.

What the machine is for

It calibrates force-measuring instruments: load cells, proving rings and force transducers, including the ones used to verify testing machines. It loads each instrument in steps to known forces, reads it beside a reference, and records the difference at every step.

Why a comparison machine

Force machines come in several kinds. A deadweight machine makes force directly from weights. Lever and hydraulic amplification machines multiply weights. A comparison machine applies force with a hydraulic actuator and compares the instrument with a calibrated reference transducer, and for very large forces several references are built up in parallel. A comparison machine is the flexible one, and its result is only as good as its reference.

Why the load has to be straight

A force instrument is made to read force along its axis. An off-axis or side load adds bending and shear, and the reading shifts. So the frame, the platens, the spherical seats and the centring adapters keep the line straight, and the instrument is turned to several mounting positions, to show how much its mounting matters.

Why the force has to be held still

Both instruments are read at the same moment, so the force must not move between them. A hydraulic loading system drifts as the oil warms and the seals creep. The actuator is therefore under fine control, and the machine waits before it reads.

Why the reference has to be known

The reference transducer sets the limit. It is calibrated against a higher standard, its drift and its response to temperature are watched, and the chain back to that standard is written down. A machine that never checks its reference is only consistent, not right.

Why the safety is part of the design

A loaded frame stores a great deal of energy. The load train sits behind a guard, an overload stop acts independently of the controller, and the force is released slowly, so that nothing is thrown.

The method

Specify, frame, align, control, calibrate, and prove.

Six steps in a fixed order. The alignment and the hold are the two that a quick order skips.

1 · Specify

The instruments, their types and capacities, whether they are used in tension, compression or both, the standard and the room are stated by the customer.

2 · Frame

A frame stiff enough for the largest force, with a base, columns and a crosshead that stay square under load, and room for the longest instrument.

3 · Align

Platens, spherical seats and centring adapters put the force along the instrument's axis. The same adapter is used every time the same instrument is calibrated.

4 · Control

A hydraulic circuit with fine control of the actuator raises the force smoothly and holds it still while it is read.

5 · Calibrate

The instrument is preloaded, run up in steps, and run down, or checked for creep where it is only used rising, then turned and run again at several mounting positions, with a wait before every reading.

6 · Prove

The reference is checked against its own record, a trial calibration shows the alignment and the hold, and the record is handed over with the machine.

Which machine, which job

Machine	How it makes the force	What to watch
Deadweight machine	weights act on the instrument directly, by gravity	the weights are large and the force changes in steps of the weights
Lever amplification machine	weights act through a lever that multiplies them	the lever ratio has to be checked, because it can change over time
Hydraulic amplification machine	weights act on a small piston that drives a large one	the piston and its friction decide the result
Comparison machine (this page)	a hydraulic actuator loads the instrument beside a calibrated reference transducer	the reference, its drift, temperature, and how steady the force is during the comparison
Build-up system	several reference transducers carry the force in parallel	how evenly the force is shared between them

The step people underrate is the hold. A force that drifts between the two readings makes a good instrument look bad, and a bad one look good.

Work content

What the machine contains, element by element.

Read it as a checklist: a machine missing a row will push a force, but not one you can sign a calibration for.

A hydraulic power unit on a plain white studio background: a flat pale grey steel reservoir box on short feet with a vertical electric motor on top at one end, a small stainless valve block with plain smooth valve bodies at the other end, a small accumulator beside it, and two thick black hoses with bright fittings leaving to the right, and no people

Fig · 03 — A hydraulic power unit: a reservoir, a motor, a valve block and an accumulator, with two hoses to the actuator — illustrative render.

Element	What it does	What matters
Loading frame	carries the reaction of the force	stiff, and square under load, with room for the largest instrument
Actuator and ram	applies the force	smooth movement, guided so that it pushes along one line
Platens and spherical seats	put the force into the instrument	flat, hard and centred, with a seat that lets the line settle straight
Centring adapters	hold each instrument on the axis	a set for each type of instrument, and the same adapter at every calibration of it
Reference transducer	is the standard	calibrated to a higher standard, with its drift checked and its record kept
Hydraulic power unit and valves	make the pressure	fine control of the actuator, and oil temperature held steady
Controls and measurement	run the steps and read both instruments	steps, holds and waits set, both readings taken together, and a record written for every step
Guard and overload stop	protect people and instruments	a guard round the load train, a stop that acts independently of the controller, and a slow release
Mounting positions	show the effect of mounting	the instrument turned to several positions and run again
Procedure	fixes the sequence	specify, frame, align, control, calibrate and prove, the same for every machine
Testing & documentation	prove the machine first	a trial calibration, the alignment and the hold shown, and a record the customer can inspect

The elements that decide whether the force is true are the alignment hardware and the fine control, and the one that decides whether it stays true is the reference record. The first two make the force, and the third keeps it honest.

Full specification — expand

Machine	A rigid loading frame; a hydraulic actuator and ram; platens, spherical seats and centring adapters that put the force along the instrument's axis; a reference transducer in the same load line, calibrated to a higher standard with its drift checked; a hydraulic power unit and valves with fine control of the actuator; controls and measurement that run the steps, holds and waits and write a record; a guard and an overload stop; a written procedure; and calibration, testing and documentation before handover
The One Idea	Load it straight; hold it still.
Why The Load Has To Be Straight	A force instrument is made to read force along its axis, and any off-axis or side load adds bending and shear that shifts its reading, so the frame, the platens, the spherical seats and the centring adapters keep the line straight and the instrument is turned to several mounting positions to show how much the mounting matters
Why The Force Has To Be Held Still	A comparison is only fair if the force is steady while both instruments are read, and a hydraulic loading system drifts as the oil warms and the seals creep, so the actuator is under fine control and a wait is kept before each reading
Why The Reference Has To Be Known	A comparison machine can be no better than its reference transducer, so the reference is calibrated against a higher standard, its drift and the effect of temperature are watched, and the chain back to that standard is written down
Standards	ISO 376 covers the calibration of force-proving instruments used for the static verification of uniaxial testing machines, and ASTM E74 is a different procedure: the two are not interchangeable, and the machine is arranged for the one the customer names. This page prints none of their limits, classes or tolerances, and no edition year: those come from the standard the customer names and from the instrument. Approval of a calibration, or of a machine, rests with the customer and the authority they name; none is claimed here
Configurations	A compression machine, a tension-and-compression machine, and a multi-range machine
Scope Boundary	This page is the force calibration machine. It is not a compression testing machine, which applies force to specimens (see compression testing machine), not a torque wrench calibrator, which checks torque wrenches (see torque wrench calibrator) and not a pressure calibration bench, which compares pressure gauges with a standard (see pressure calibration bench). A load cell and a proving ring are different equipment again. No certification or accreditation is claimed here
Status	Neometrix engineers force calibration machines to order, and no delivered force calibration machine is claimed.

Configurations

One method, three ways to build the machine.

The method, the alignment hardware, the fine control, the reference record and the procedure are shared. What changes is which way the machine loads and how wide a span of force one frame has to cover.

Compression machine

The frame pushes the instrument between two platens

A loading frame, an actuator, a reference transducer and a load train, for load cells, proving rings and force transducers that are used in compression.

Tension-and-compression machine

The same frame, pulling as well as pushing

Tension adapters and a frame arranged to pull as well as push, for instruments that are used in both directions and have to be calibrated in both.

Multi-range machine

A reference for the small forces and one for the large

Two or more reference transducers of different capacity in one frame, so that a small force is read on a small reference and a large force on a large one, each in the comfortable part of its range.

And the part that is not equipment at all, yet decides all three: the procedure and the test plan. They fix the instruments, the steps, the holds and waits, the mounting positions, the order they run in and what is recorded. They are written from the customer's own instruments and standard, not from the frame.

The drawings

A reference set, drawn as real CAD sheets.

Four sheets of one reference configuration: the general arrangement, the hydraulic and measurement schematic, six construction details, and the laboratory with its calibration sequence and trips. They show how the machine goes together and what it does when something goes wrong. They carry tags and arrangement only. Every force, pressure, class, time and size is fixed by design for the customer's instruments and standard.

Reference drawing sheet one, the general arrangement of a compression force calibration machine. A front elevation shows a base plate on levelling feet, two columns and a crosshead, a hydraulic actuator and ram at the centre of the base, and on one vertical centre line a lower platen, a spherical seat, a reference transducer, a second spherical seat, the instrument under calibration, a third spherical seat and an upper platen, with a dashed clear guard round the stack, two hoses to a hydraulic power unit beside the frame, and cables from the two transducers. A side elevation shows the same machine from the right. The overall dimensions are marked with the letters A, B, C and D, and two tables list fourteen numbered items

Fig · 04 — Sheet 01, the general arrangement: the frame, the actuator, and the load train on one centre line, in front and side elevation. Reference configuration, sizes set by design.

Reference drawing sheet two, the hydraulic and measurement schematic. A power unit with a reservoir, a motor and pump, a filter, a check valve, a relief valve, an accumulator, a solenoid shut-off valve, a slow-release valve and a fine-control valve feeds an actuator whose ram pushes through a reference transducer and the instrument under calibration against the frame. Each transducer goes to its own readout, and a force controller takes the reference reading and commands the fine-control valve. Interlock logic takes inputs from the guard, the force, the pressure, the oil temperature and the emergency stop, and trips the shut-off and the release valve. A legend, nine notes and a title block stamped reference configuration, not for construction

Fig · 05 — Sheet 02, the hydraulic and measurement schematic: the actuator under fine control, the two readouts, and the interlocks that act apart from the controller. Reference configuration, tags only.

Reference drawing sheet three, six construction details. The first shows the load train on one centre line through every element. The second shows a spherical seat in section, a ball in a cup between two plates. The third shows a centring ring on a platen holding an instrument base in its recess, with a plan view. The fourth shows an off-axis load beside a straight load on an instrument, with the offset marked by a letter. The fifth shows an instrument turned to three mounting positions in plan. The sixth shows the guard, the guard switch and a mechanical overload stop beside the ram

Fig · 06 — Sheet 03, six details: the load line, the spherical seat, the centring ring, off-axis against straight loading, the mounting positions, and the guard with its overload stop. Reference configuration.

Reference drawing sheet four, the laboratory arrangement. A plan of a temperature-controlled room shows the machine on an isolated foundation slab, the hydraulic power unit, a control desk, a store for reference transducers, an instrument bench, a door, an air supply and return, and a room temperature sensor. The sheet also shows the six-step calibration sequence from conditioning to the record, and a table of causes and effects for the trips

Fig · 07 — Sheet 04, the laboratory: the plan, the six-step calibration sequence and the table of trips. Reference configuration.

Every real machine is drawn for its own instruments, room and standard. These sheets are the arrangement, the details and the order of work that a project set starts from. Approval of any drawing rests with the customer and the authority they name; none is claimed here.

PDF · four sheets

Reference drawing set — arrangement, schematic, details, laboratory

PDF · capability sheet

Force calibration machine — what Neometrix engineers

Where it is used

Wherever a force reading is taken on trust, and someone has to check it.

The common thread is a force instrument that a decision rests on, and a calibration that has to show how far it can be trusted.

Calibration laboratories

Where force instruments are calibrated against traceable references for other people.

Test houses and materials laboratories

Where testing machines are verified with force-proving instruments, and those instruments must be calibrated first.

Makers of load cells and force sensors

Where each instrument is calibrated before it leaves the maker, and the same machine shows how much its mounting matters.

Plants with their own testing machines

Where in-house machines are verified on a schedule, and the instruments used for it are kept calibrated.

Watch

See it in motion.

A short walkthrough video of the force calibration machine.

FAQ

Common questions.

Longer answers, for readers who want the reasoning.

Q · 01 What does a force calibration machine actually do?

It loads a force-measuring instrument to known forces and compares its reading with a calibrated reference. The machine applies force with a hydraulic actuator, holds it steady, reads the reference and the instrument at the same moment, steps up and, where the instrument is used in both directions, steps down, and records the difference at every step. It does not decide whether an instrument is acceptable: that is the job of the standard and of the people who name it.

Q · 02 Why a comparison machine, and not a deadweight machine?

A deadweight machine makes force directly from weights, and it is the most direct way to do it, but its weights grow with the force and the force changes in steps of the weights. A comparison machine uses a hydraulic actuator, so one frame covers a wide span of forces and many kinds of instrument, and its result rests on a reference transducer that is itself calibrated against a higher standard. The price is that the reference, its drift, temperature and the steadiness of the force all enter the result. We set those out in the test plan, and the chain back to the higher standard is written down.

Q · 03 Why does the load have to be straight?

Because a force instrument is made to read force along its axis. A load that is off-axis, or a side load, adds bending and shear, and the reading shifts, so the same instrument can read differently when it is mounted differently. Spherical seats let the line settle straight, centring adapters hold the instrument on the axis, and the instrument is turned to several mounting positions and run again, to show how much its mounting matters. The same adapter is used every time the same instrument is calibrated, because a different one can shift the result.

Q · 04 Why does the force have to be held still?

Because the reference and the instrument are read together, and if the force drifts between the two readings the difference is wrong. A hydraulic loading system drifts as the oil warms and as seals creep. Fine control of the actuator holds the force still while it is read, the oil temperature is kept steady, and the machine waits after each change of force before it reads, so that both instruments have settled. An instrument that is used only while force is rising is also checked for creep, which is how it behaves when the force is held.

Q · 05 Is this the same as the compression testing machine, the torque wrench calibrator or the pressure calibration bench?

No, and the differences are worth stating precisely. The compression testing machine page covers crushing specimens in a stiff frame, a machine whose own force reading is verified with the kind of instrument this page calibrates. The torque wrench calibrator page covers checking torque wrenches. The pressure calibration bench page covers comparing pressure gauges with a standard. This page is the force calibration machine, for load cells, proving rings and force transducers. 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 force calibration machines to order, and no delivered force calibration machine is claimed. What stands behind the offer is adjacent: Neometrix engineers a pressure calibration bench (see the pressure calibration bench page), a torque wrench calibrator (see the torque wrench calibrator page) and a compression testing machine (see the compression testing machine page). The reference transducers, indicators, amplifiers, hydraulic pumps, valves and logic controllers are catalogue items, bought in, not invented. What Neometrix engineers is the machine around them: the frame, the load train and the alignment hardware, the hydraulic circuit, the controls, the procedure and the record. So the honest position is that the machine is engineered to order, the neighbouring disciplines are in the building, and the first machine of this exact kind will be built around the customer's own instruments rather than taken off a shelf.

Q · 07 Which standard applies, and what can the machine not do?

ISO 376 covers the calibration of force-proving instruments used for the static verification of uniaxial testing machines. ASTM E74 is a different procedure, and the two are not interchangeable, so the machine and its procedure are arranged for the one the customer names. This page prints none of their limits, classes or tolerances, and no edition year: those come from the standard the customer names and from the instrument. The machine compares and keeps a record. It does not make a laboratory competent and it does not certify an instrument: this page claims no certification or accreditation. No force, pressure, class, 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 instruments rather than the machine. First, the instruments: the kinds you calibrate, their capacities and how they are mounted. Second, the directions: whether they are used in compression, in tension or in both. Third, the standard you name, and the procedure it sets. Fourth, the reference: whether you already own reference transducers and how they are calibrated. Fifth, the room: its floor, its height and its temperature control. Sixth, the record: what you want kept for every instrument. From that we come back with a machine 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 crushes specimens, one checks torque, one compares pressure.

↗ Specimens

Compression Testing Machine

Crushes specimens in a stiff frame - a machine whose own force reading is verified with the instruments this page calibrates.

↗ Torque

Motorized Torque Wrench Calibrator

Checks torque wrenches against a computerized reference - a tool calibrated for the torque it applies, where this page calibrates instruments that read force.

↗ Pressure

Pressure Calibration Bench

Compares every gauge with mass, area and gravity - the standard for pressure, where this page calibrates instruments that read force.

Browse all Neometrix product lines.

Get a quotation

Tell us the instruments,
and the standard you work to.

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

Enquire — force calibration machine Capability sheet (PDF) +91 7777 876 876

ISO 9001 / 14001 ENGINEERED-TO-ORDER CLASS — FORCE CALIBRATION MACHINE SPECIFY · FRAME · ALIGN · CONTROL · CALIBRATE · PROVE — LOAD IT STRAIGHT; HOLD IT STILL ENGINEERED IN NOIDA · INDIA