Saturday, May 18, 2019
HAL, Inc. is a major manufacturer of computers and computer components Essay
HAL, Inc. is a major manufacturer of computers and computer components. In one of their plants they made printed circuit boards (PCBs), which were used by early(a) plants in the company in a variety of computer products.The basic process runs 3 shifts per twenty-four hour period and it can be briefly depicted by following flow diagramOptical Test-internalPro-Coat fuzz plateDrillingOptical Test- externalEnd of line testSizingMachiningLamination core treater procMessInternal circuitizeLamination compositeExternal circuitizeThe targeted output for the plant is 3000 boards per sidereal day, five days a week, with plant trial three shifts per day. alone the plant has been failed to reach and maintain the targeted throughput at a steady consider due(p) to manufacturing complexities associated with the product mix. It was also found that, the output of the pro-coat process is very slow (1200 boards/day) compared to the expected throughput and therefore Hal has to consider a vendor o n the pro- coat process to fulfil the demand. This engagement of vendor has caused subjoin in cost per board and two days delay because of shipping up and back. So the Hal is striving to increase the throughput of the pro-coat process and the purpose of this case study is to provide some guidance to them in their effort by giving somerecommendations to improve the existing system.Floor arrangement and the work flow of the pro-coat process free-and-easy demand = 3000 boardsWorking hours = 24- (Breaks + Lunch + shift change + Meeting)= 24-(20X2X3+40X3+10X3+90/5)= 19.2 hrs requisite= 3000/(19.2X60)= 2.604 boards/minAssumption1. Demand = Arrival sum up (ra=2.604 boards/min)2. Arrival pattern exponentially distributed (Ca2=1)Machine Name Mean process (load) condemnation (min) Std. Dev. Process Time (min) Trip Time (conveyor) (min) MTBF (hr) MTTR (hr) Setup time (min) Availability Number of machines Rate per day Clean 0.33 0 15 80 4 0 0.95238 1 3325Coat 1 0.33 0 15 80 4 0 0.95238 1 332 5Coat 2 0.33 0 15 80 4 0 0.95238 1 3325Expose 103 67 0 300 10 15 0.96774 5 2834 Develop 0.33 0 2.67 300 3 0 0.99010 1 3456 Inspect 0.5 0.5 0 0 0 0 1.00000 2 4608Bake 0.33 0 100 300 3 0 0.99010 1 3456MI 161 64 0 0 0 0 1.00000 8 3435Touchup 9 0 0 0 0 0 1.00000 1 7680Once analysed the Hal pro coat process, the break work station (highlighted in above table) has been found as bottle neck operation under the 19.2 working hour positioning. But the company goal is to achieve 3000 boards per day. If the company operate under the optimum condition, 2,834 boards could be produces, which is still under the company goal. According to the given data in the case was deeply analysed as follow. Assumption charge and MI are manual operations. So number of work benchers has been considered as 8 in MI operation and 2 in inspection work station. It could be possible to eliminate the bottleneck situation by adding resource (No of operators).1. CleaningEffective touch time (te) = t0A= 0.33/0.95238= 0 .3465 minUtilization (u) = rax te= 2.604 X 0.3465= 0.902Ce2= C02+1+Cr2A(1-A)mrt0Ce2= o+1+00.95238(1-0.95238)2400.33= 32.98De set abouture rate Cd2=u2Ce2+(1-u2)Ca2= 0.9022x 32.98+1-0.9022x 1= 27.019cd2 =27.0192. Coat 1Similarly,Effective impact time (te) = 0.3465 minUtilization = 0.902Ce2= C02+1+Cr2A(1-A)mrt0ce 2 =32.98Cd2=u2Ce2+(1-u2)Ca2= 0.9022x 32.98+1-0.9022x 27.019cd2=31.873. Coat 2Similarly,Effective processing time (te) = 0.3465 minUtilization = 0.902Ce2= C02+1+Cr2A(1-A)mrt0ce2 =32.98Cd2=u2Ce2+(1-u2)Ca2= 0.9022x 32.98+1-0.9022x 31.87cd2=32.774. Coating and exposeSince the coating 2 processing rate greater than the arrival rate of the pro- coat system. Arrival rate of the expose machine govern by the arrival rate of pro-coat system Expose machine calculations based on jobs (60 boards = 1 job) Arrival rate =2.604/60=0.0434 jobs/minBuffer size = 05Blocking size = (buffer size + maximum jobs in expose machines)= 5 + 5b = 10ra=0.0434Ca2=32.77Coating 2Expose= 10 preventative outage s Effective processing time (te) = t0A= 103/0.9677= 106.43 minAssumption Number of boards between setups = 120Total rough-and-ready processing time (Preemptive and Non-preemptive outages) (te) = t0A+tsNsx job size= 1.720.9677+15120x 60= 114.14 minAssumption Standard deviation for muddle = 0 min (constant distribution) Preemptive outage variance = 02A2+(mr2+r2)(1-A)t0Amr=672.96772+6002+01-0.96771030.9677600= 6856.43Preemptive outage SCV Ce2= C02+1+Cr2A(1-A)mrt0= 6721032+1+0x0.96771-.9677600103=0.6052Assumption- No variation in setups (constant distribution)Total variance (preemptive + non-preemptive outage) = 02+s2Ns+(Ns-1)Ns2ts2= 6856.43+0+(120-1)1202152=6858.29SCV for expose(preemptive + non-preemptive outage) ==Ce2= e2te2= 6858.29114.142= 0.526Utilization for expose = raxtem= 0.0434114.145=0.99Arrival SCV for batch = Arrival SCV for individual part/batch size= 32.7760= 0.546U
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