TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Large Force Standards and Dissemination by using Build-up System

Large Force Standards and Dissemination by using Build-up System

Force and Torque Metrology for the Sustainable Development In South American Industries

Dr. Dae-Im Kang, TC-3 Chairman

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Contents

Introduction Deadweight and hydraulic force standard

machines Build-up system Build-up force standard machine Large force dissemination by using build-up

system Summary

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Industries in South America

General Index in Economic Conditions(2004)

Industrial Structure

Population (Million)

GDP

(mUSD)

Trading

(mUSD)

Brazil 181 604,870 159,240

Argentina 38 151,298 56,775

Chile 15.9 90,800 54,956

AgricultureForestry

Stockbreeding

Mining Industry(Iron, Aluminum)

Food industryTextile industry

Iron industryAutomobile industry

Aircraft industry

30 % of GDP 30 % of GDP

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Needs of Large Force in South America

High economic growth 1st industries 2nd industries Increase of high technology industries Increase of heavy industries

Needs of accurate measurement

Needs of high capacity measurement

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Deadweight Force Standard Machines

KRISS 100 kN DFSM

PTB 2 MN DFSM

KRISS 500 kN DFSM

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Deadweight Force Standards (1)

Deadweights

Loading frame

Force measuring device under

calibration

Force by gravitational field (g)

w

alocmgF

1

: local gravitational acceleration

aw

locg: density of air

: density of deadweight

F : Force

m : mass of weight

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Deadweight Force Standards (2)

Most accurate force standard machine (2x10-5)

High cost and size for large force

Deadweight force standard machines in the world 4 MN : NIST(USA) 2 MN : PTB(Germany) 1 MN : PTB(Germany), NPL(UK), IMGC(Italy),

NIM(China) … 500 kN : KRISS(Korea), NMIJ(Japan), NMIA(Australia),

LNE(France), CEM(Spain) …

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Hydraulic Force Standard Machines

KRISS 2 MN HFSM PTB 16.5 MN HFSM

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Hydraulic Force Standards (1)

QmgFw

alocw

1

1

2

A

AQ

m

wF

Control system

PPv

Unsealed

1A 2A

Force transducerworking system

F

Leakage Oil

Measuring system(pressure balance)

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Hydraulic Force Standards (2)

Amplification of force (Q) by hydraulic system Amplification factor : 200 ~ 1000

Relative Uncertainty : 1x10-4

Possibility of large force standards

Complex technology and still high cost

Hydraulic force standard machines in the world 20 MN : NMIJ(Japan), NIM(China) 16.5 MN : PTB(Germany) 5 MN : PTB(Germany) 2 MN : KRISS(Korea)

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Economic Way for Large Force

Deadweight Force Standards

Hydraulic Force Standards

High cost and size

High cost and complex

technique

Needs of more economic and effective way to generate large force

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Build-up Force Measuring System

Three equal force transducers

loaded in parallel Force

measurement capability

increased to three times

Calibration of each force

transducer in a deadweight or a

hydraulic force machines

Evaluation of the build-up

system

Used in combination the output

have to be added or averaged

Force transducer

F

Load button

Middle platen

Base platen

120o

FT B

120o

FT C

FT A

x

y

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Build-up Force Standards (1)

Pump

Upper compression head

Column

Cylinder

Oil

Force measuring deviceto be calibrated

Pressure sensor

Motor

Ram

O-ringBuild-up system

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Build-up Force Standards (2)

Force comparator with the reference of build-up force measuring system

Easy way to reach large force

Relative uncertainty : 2x10-4

Build-up force standard machines in the world 30 MN : NPL(UK) 10 MN : KRISS(Korea) 9 MN : LNE(France)

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

10 MN Build-up FSM in KRISS

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Uncertainty of Build-up FSM

Uncertainty of the build-up system (%) Repeatability 0.00298 Resolution 0.00005 Interpolation 0.00007 Zero recovery 0.00088 Temperature variation 0.00012 Creep 0.00277 Long term sensitivity drift 0.00289 Reference force 0.005 Combines uncertainty : 0.00712

Uncertainty due to servo control (%) Repeatability 0.00048 Deviation from target value 0.00025 Resolution 0.00004 Combined uncertainty : 0.00054

Expanded uncertainty of build-up FSM (%) 0.01428 Declination of 0.02 %

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Comparison with 2 MN Hydraulic FSM

Relative deviation < 0.005 %

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Large Force in Industries, Korea

30 MN Pot-bearing Testing Machine

Increase of heavy industries Needs of larger force

Needs for evaluation of mechanical components such as pot bearings Testing machines with capacities greater than 10 MN

15 testing machines in Korea

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Large Force Dissemination using B.U.

10 MN Build-up Force Standard

Machine

10 MN Build-up Force Standard

Machine

Calibration of 10 MN Force Transducer

Calibration of 10 MN Force Transducer

Establishment of 30 MN Build-up systemEstablishment of 30 MN Build-up system

Dissemination of large force up to 30

MN

Dissemination of large force up to 30

MN30 MN Build-up system

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Summary

Build-up system Parallel combination of force transducers Capability of large force measurement

Build-up force standard machine Force comparator with the reference force from build-

up system Easy and economic way to establish large force

standards

Large force dissemination by using build-up system Large force up to 3 times of the force standards

TC3 Workshop, IMEKO XVIII World CongressRio de Janeiro, Brazil, Sept. 19, 2006

Thank you for your attention!