8 d lift onload ft

7/31/2019 8 D Lift Onload FT

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1

Objective of 8 D Review

Progress review of all the 10 8D Teams

Out come of the 8 D steps

Support required by teams from

PU HeadsMr. Anil Menon


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8 D Problem Solving on

FT - Hydraulic Lift On Load

Project start Date - 14 Sept12


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4

Progress Summary :


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7

D2 : Problem Definition

S.No Factors Problem Details Comparative Study Inference (which should

be analysed further )Is Is not

Differences / Changes

1WHO reported the problem? 1. Test Rig 1.FTA Tet Rig is equipped with Pressure Gauge

which is showing the pressure value/directly

indication of the problem. Whereas in FTA

there is no pressure gauge, Engine noise level

is the criteria to identify the problem which

depends on skill set of Operator.

1. Variable inspection

facility is not available at

FTA level.

2. Operator dependent

inspection at FTA.

2WHAT is part

number/description?

FT 30, 45, VMX, AMX, FT 60,

FT 60 SMX, FT 60/65 EPI.

Nil Problem persists in all FT models.

Concentration is more in Heavy Liftcompared to Normal Lift.

Capacity of normal lift is

1050 kg, & heavy lift

1500 kg load variation

3WHAT is problem ? After Lifting, Lift not

achieving neutral circuit.

Pump is taking load.

Nil

4WHAT is measurement

method ?

Hyd. Test Rig using Pr. Gauge with 'OK' /

'NOT OK' decisions (Attribute).5What is potential/actual

effect to the customer / in

the field (As stated by

Customer).

Engine taking load by noise difference,

Pump failure.

6What could be commercial

impact over this problem.

Increase in Cost of Poor

Quality.

7If the product is being

assembled in using multiplelines, which lines is causing

problem ?

N/A since being assembled in

single line.


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S.No Factors Problem Details Comparative Study Inference (which

should be analysed

further )Is Is notDifferences / Changes

8 If the product is being tested in usingdifferent Test Rigs, which Test Rig

problems are reported ?

On all 3 test rigs

9 What item has got the problem. Cylinders sub assly. (

in most of the

cases).

It is not in all the cases. Data not available To conduct further

study on OK assy and

Not OK assy.

linkages of hydrualic

assly. (in few cases).

Its not in all the cases. To conduct further

study on OK assy and

Not OK assy.

10 What all are the items which can lead

the problem (Boundary Diagram).

Attached

11 What similar product could has the

problem but doesnot seen/reported.

N/A.

12 When the problem was first

noticed/found ?

Since beginning.

13 When it is noticed after 1st time? Continuous

14 Where on the components the problemnoticed ?

N/A.

15 Where is the process flow/ sequence

the problem is noticed?

Test Rig Operation

no. 110

16 Where on the product, geographically

the problem was seen?

N/A.

17 When in the product life cycle, this

problem is noticed,

1. Infant mortality

2.Warranty Failures3.Due to wear and tear ?

Infant Mortality


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9

11.8

15.9

22.8

19.2 19.2

40.2

26.5

9.4

18.721.3

25.6

0

5

10

15

20

25

30

35

40

45

Oct-11 Nov-11 Dec-11 Jan-12 Feb-12 Mar-12 Apr-12 May-12 Jun-12 Jul-12 Aug-12

DPTT

Month

D2 : Problem Definition :

How Much : On load Defect trend ( Test Rig )


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How Big : Pareto Diagram of all defects at Test Rig ( Last 6

Months)

42.1

23.6

13.4

2.5 2.4 1.7 0.2 0.0 0.00.010.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

0.05.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

M/c

Drop

Onload Not

lifting

Linkage

fault

Jerking Slow

lifting

Sticky Lifting

not

proper

Main

cover

leak

AxisTitle

Defects at Test Rig


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D2 : Boundary Diagram

Hydraulic

Pump

OIl

flow

sensor

Main

Cover

Coveracces

sory

Draft &

Position

control

lever

Yoke

assly

Lift

Arm

Ram

Arm

Pisto

n

Cylinde

r assly

Linka

ges

Pr. Relief Valve

Dead

Weigh

t

Test Rig machine body DirtyOil tank

Clean

Oil

tank


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Hyd lifton load

Piston , Ram arm&Yoke

LinkagesCylinder Subassly

Test Rig

Torsion spring stiffness not O.K.

Machine body fouling with Ram arm

Contaminated oil

Cam Profile

on ram not ok

Piston Under size

Hydraulic pump malfunctioning

Main cover subassly

Pr. Relief valve settingInternal leakages

Poor Face

roughnessCheck valve

seat bore dia

O/S

Blow Holes/ porosity in cydActuator lever sticky

Cyd. Hole block / missNPT Plug loose / miss

Cylinder main Bore O/SInternal leakage in cylinder

U/L valve stickyC.V sticky

CD of connecting rod seat and piston face

Linings / scratches in main bore

C.V. setting ( 30 Thou )

Safety valve leakF/V sticky / tight

U/L valve hole blockF/V hole blockC.V. hole block

Internal galleries block due to

contaminationBaffle plate loose

Linkage bend

CoverAccessory

Linkage foulingHole interconnected

Blow holes

Hole block

Hole U/S or block

Inlet Hole O/S

Master spline

shift in Ram Arm

Play in Yoke

Connecting Rod& Serr. Shaft

Conn. Rod O/S

or U/S

Spline shift inserr. shaft

U/L valve plug O ring cut

F/valve plug O ring cut

Cylinder face O ring cut

y2 y3y1

y4 y5 y6 y7

Y


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y Factor Causes April May June July August Sept Total

y1 Cylinder sub assly

Cylinder Sub assly changed 8 5 21 21 24 44 123

C.V. setting 0 0 0 2 1 1 4Actuating lever 0 0 1 0 0 0 1

Face O ring cut 0 2 1 0 2 2 7

F.V. valve tight 0 1 9 2 3 6 21

Baffle plate loose 0 0 1 2 1 4

Plug O Ring cut 2 1 0 3 0 4 10

Cylinder dia 90 O/S 0 0 0 0 8 0 8

Spring setting0 0 1 0 0 0 1

y2 Linkages Draft link fouling 1 0 1 0 0 0 2

y3 Cover Acc. Cover acc. Changed 0 0 1 0 0 1 2

y4 Test Rig Pump changed 0 0 0 2 0 2 4

y5 Main cover Sub assly

Main cover hole U/S 0 0 0 0 1 0 1

Seat Change 0 0 1 0 0 2 3

y6 Piston , Ram Arm & Yoke Ram arm changed 0 1 2 0 1 0 4

y7 Conn. Rod & Serr. Shaft 0 0 0 0 0 0 0

Not known 0 4 1 1 2 2 10

Total 11 14 40 33 43 64 205

0.0

20.0

40.0

60.0

80.0

100.0

0

50

100

150

200

Cylinder sub assly Not known Test Rig Main cover Sub

assly

Piston , Ram Arm

& Yoke

Linkages Cover Acc. Conn. Rod & Serr.

Shaft


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S.No Activity Result

1. Check valve replaced No Change

2. Torsion spring changed No change

3. Unload valve O ring changed No change

4. Complete attachment ( including rear plate ,

torsion spring , actuator lever control lever & roller

No change

5. 30 thou setting done again No Change6. Replacement of cylinder Problem solved

Cylinder no :- UF 017 , lift no. 1157 , Normal

Problem : Onload

Date :- 26.09.2012Team :- Mr. Ritesh ( KMC ) , J Sabarwal , L.R. Kaushik , Sajal Verma , Shlvinder Singh (rework opt. ) , S. Rajneesh & Manoj Giri

Other Observations :Contaminations not seen

All plug O rings found O.K.

All valves holes ( C.V. / F.V. / U.V. ) found O.K.

Baffle plate was tightened properly

Cylinder Face O ring found O.K.


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8 d lift onload ft

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