IRJET- Experimental Investigation on Partial Replacement of Dunite as Cement
Dan's state, repairs, and production
1. STATE OF THE QUALITY SYSTEM
“A job is not worth doing unless it is worth doing well.” - Albert H. Luhrman
The following describes how reliable the goods and services are that we provide, and how reliably
we provide them. More importantly, it details what exactly we are doing to continuously improve
both. This should decrease instruments sent to REPAIRS, lower PRODUCTION costs, and
increase VENDOR reliability.
REPAIRS
TABLE 1 – ALL CURRENTLY PRODUCED UNITS
UNIT 12 MONTH AVG. % OF ALL AVG. UNITS % OF THIS % THIS
MONTHLY PRODUCED RETURNED / INSTRUMENT INSTRUMENT
PRODUCTION MONTH THIS RETURNED MANUFACTURED
PERIOD OF ALL THAT ARE
RETURNED RETURNED
313 1139 36 45 24 4.0
330 269 8 30 16 11.2
340 907 28 49 27 5.4
360 52 2 18 10 34.6
386 624 20 35 19 5.6
396 176 5 5 3 2.8
618 32 1 1 1 3.1
Total 3199 100 184 100 5.8
(A) PRODUCTION, RETURN, and WARRANTY
Instrument Production was down a slight 2% in the last four months, yet the return percentage
was up 1.5%. 54% of repairs were covered under warranty (last period had 4% less covered by
warranty).
(B) TuffTemp UNITS
TABLE 2 – TUFFTEMP RETURNS
UNIT 12 MONTH % OF ALL AVG. UNITS % THIS % THIS
AVG. MONTHLY PRODUCED RETURNED / INSTRUMENT INSTRUMENT
PRODUCTION MONTH RETURNED MANUFACTURED
THIS OF ALL THAT ARE
PERIOD RETURNED RETURNED
330 269 8 30 16 11.2
340 907 28 49 27 5.4
386 624 20 35 19 5.6
396 176 5 5 3 2.8
The TuffTemp Line averaged 119 repairs per month, or 6.0% that are produced are returned - a
slight increase of 1.6% from the TuffTemp return percentage of last period (again). Here’s why:
330 - 10 per month average due to Corroded Boards (was 13 last period)
340 - 16 per month average due to Corroded Boards (was 9 last period)
386 - 32 per month average due to L11 (with 16 per month average due to “Bad Component”)
396 - 3 per month average due to L11
This period began noting difference between returns, and returns that were not working.
2. (C) SPECIFIC REPAIR ISSUES
Burger King had complained of cable breaks on some of their probes. The returns due to cable
problems specifically from Burger King was reviewed and found to be statistically insignificant.
Component L11 is the single biggest repair issue on the VersaTuff units. On average twenty
386/396 units come back each month with this problem (2% that are made, come back with this
problem). Component L11 is an inductor that goes out when the unit encounters a jolting shock
such as being dropped onto a hard kitchen floor.
(D) CONTINUAL IMPROVEMENT for Repair System
Platinum cable redesign is in progress not economically possible because too little cable would
be ordered for Judd Wire to produce a run of new cable.
Additional codes for the TuffTemp units have been added which have helped to denote difficulty
with Component L11 on the VersaTuffs. Diagnosis and repair outlines specific to each instrument
continue being revised by Engineering.
VENDOR PERFORMANCE
“Art is making something out of nothing and selling it.” - Frank Zappa
On-time deliveries were 9 something…
TABLE 4 – VENDOR ISSUES
Vendor Part Number and Problem(s) Date Corrective /
Description Began Preventative Action(s)
Axon Circuits PD5118 Untested Boards 4/2002 Shipped boards back
DeMark PD0189-x Plastic too soft, 3/2002 Seeking new vendors
All coiled cables pins coming out,
burnt, wires
coming out
Eastek PD1389-10 bad insert, 7/2001 No shipments with
Type K Miniconn. wrong plates consistently all good
inside parts
NSM PD0250-34/41 Screw Boss too 2/2002 NSM to check openings
330/340 Housings wide to specific measurement
Stock PD2694-16 Wrong switch 8/2002 Sent back, got E-switch
Components replacements
3. PRODUCTION
“Never confuse motion with action.” - Ben Franklin
TABLE 3 – PRODUCTION SUCCESS
DEPARTMENT AVERAGE PRODUCTION AVERAGE SUCCESS
MONTHLY TREND SINCE MONTHLY TREND SINCE
PRODUCTION LAST REPORT SUCCESS LAST REPORT
(THIS 4 MOS.) (%) RATE (%) (%)
PCB 3737 Up 2 70 Down 2
Instrument 3726 --- 97 ---
Probe 11,724 Up 2 93 Up 4
Average N/A Up 2 90 Up 4
The Success Rates are computed from work completed w/out reworks and rejects. The
(A)verage Success Rates, (B)ig Issues, and (C)ontinuous Improvements for each
department are summarized below.
PCB
(A) Average Monthly Production of PCBs is up slightly, success rate fairly steady. This is 4%
below the annual success rate.
(B) The biggest defects are still due to Solder Shorts and Solder Opens (20% of all boards made
were reworked due to this). 745 boards per month have solder short or solder open problems
during build, and 3 more are returned each month with solder open. This will take an average of
3 to 4 hours per month to repair.
(C) A new solder screen printer machine (that will evenly disperse the solder layer) is scheduled
for purchase November 2002 (back from July of 2002). Engineering continues to work on
designs with standard components and alternate manufacturers. Board design changes are
made when economically justifiable.
INSTRUMENT LINE
(A) In this reporting period, both production, and success rates, remained steady for instruments.
(B) The largest problems in the instrument line were not exactly with the instrument line, but with
the instrument housings. The screw boss openings were too large, thus not allowing enough
surface for the fasteners to bite.
(C) Northern States Metals (the housings vendor) has specific dimensions now for the opening,
and will inspect and hold that in the future.
PROBE LINE
(A) The production has increased by 2%, and the success rate has rose 4% percent.
(B) Tubing pre-testing continues to pay off with less than 5% failure in sub-assemblies.
(C) Engineering and Purchasing have smoothly transitioned to DeMark as the primary coiled
cable vendor. The cables were having some problems with pins pushing in due to rubber that
was too soft. The problem was rectified, and no consistent, substantial (over 5%) problems with
the Type K coiled cables have occurred.