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论老子

道,领导也。领导必需要不断呼唤,教导下属以及以身作则。下属的过和错皆因领导懒惰。

 
 
 

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Chapter 18: Waste of processing  

2012-06-24 12:07:58|  分类: Buffer Mentality |  标签: |举报 |字号 订阅

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A year after implementing small lot production schedule in Eastern Steel Services, the factory output went up four times to 12,000 tons per month. The general manager asked me if I could push the output by another fold.

I replied, “That is a tall order. Raising the productivity four folds without adding machinery or manpower is already an enormous feat. We had accomplished that. To repeat the feat and double its output now means raising the productivity by a factor of eight. That is quite impossible.”

“But I have no choice,” he said, “That is a firm directive from the parent company. I better achieve that output number.”

I studied the entire production system and the customer delivery requirements. I then figured out a method to match the two of them by limiting the production schedule to twelve job orders per production batch or run. All the managers agreed unanimously. This was not a problem. The yield loss did not go up significantly higher than the current 1.6%.

But I interjected with an additional request. We had to buy a fleet of twenty four trailers. “What? Eastern Steel Services is not a transport company. Certainly we were not going into the transport business,” exclaimed the general manager.

I explained that twelve of these trailers would be parked right inside the back-end of the factory. Bundles of cut-and-bent rebars are to be hoisted from the bending machines directly onto these trailers. When these twelve trailers were fully laden with the twelve job orders, these trailers would be towed out of the factory to dedicated trailer lots marked along side the factory building. The next batch of twelve trailers would be moved into the factory. The process of transferring the freshly cut-and-bent rebars onto the next twelve set of trailers then resume. 

With the introduction of trailers into the factory floor, cut-and-bent rebars will no longer be placed on the factory floor. Neither would there be a need for the material handlers to search from among the more than a hundred bundles of rebars to group them together into different piles identified by a dozen job orders. The material handlers also do not have to hoist the bundles of rebars from the floor to the trailer.

The entire sequence of placing the cut-and-bent rebars onto the floor, searching for the right bundles of rebars, congregating the bundles of rebars into their respective job orders were completely eliminated. These processes were in the first place a sheer waste of processing.

 

Figure 18-1: After removing the doubling of the finished goods



The General Manager asked, “Would the elimination of these unnecessary processes of hoisting and searching for rebars be able to raise the productivity to twice its current level?”

I replied, “No. At best the productivity shall increase by another 50%. That increase in 50% in productivity is quite stunning, isn’t it? The next 50% has to be met by capital investment to purchase the third full set of shear and bending machines.”

The investment was made and twenty-four trailers were brought in. In six month’s time, the new shear and bending machines were brought in and the productivity went up to twenty-four thousands tons per month.  

 

Illustration #1: Handling of scrap metals

 

Faced with the decision to reduce the space occupied by the scrap yard at NatSteel Ltd, the group’s General Manager asked me to visit a few steel mills in Europe to observe how they handle scrap metal. Several of these steel mills deployed heavy duty excavators armed with a long and extendable arm with a set of powerful claws at the end that can grasp half a ton of scrap from the floor level and stack them high up to a height of nine meters.

When a truck load of scrap metal arrives, it takes less than five minutes for the scrap metal to be unloaded from the truck and stacked up high into the nine-meter tall pile of scrap metal. Fast and efficient were the only words that came out from my mouth.

Back in Singapore I wrote in my trip report what I saw in Europe. But towards the end of the report I had to write my recommendations. Shall I go ahead and follow what the Europeans do?

I made an assessment on the factory space requirement of NatSteel Ltd and its subsidiaries. Land rental in Singapore had gone up sharply in the last few years. To cut cost, NatSteel Ltd had to give up part of its huge scrap yard. Simply stacking up the scrap nine-meter high can free up a lot of space. Possibly, half the existing scrap yard can be freed up. That would meet the original purpose of my visit to Europe.

A review into the need of the scrap yard indicated clearly that scrap that went into the scrap yard was for temporary storage only. It should go straight into the blending yard located next to the furnaces. Because the blending yard was too small excess scraps were off-loaded into the scrap yard.

However, a quick study on the volume of scrap purchased from the Singapore local scrap collectors indicated that these purchases met only 60% of the steel mill’s daily consumption. The remaining 40% were made up from the imported scraps stacked up in the scrap yard.   

I recommended two strategies to free up more space in the scrap yard.

One, direct all the local scrap to the blending yard. Do not allow them to be off-loaded at the scrap yard. This eliminated the double handling of the scrap. This avoided the unloading of scraps into the scrap yard and later loading them up again onto the internal trucks that transfer them to the blending yard.

Two, when the ship laden with imported metal scrap arrived at the Singapore port, the scrap yard shall hire a few excavators to carry out the unloading of scrap metals at the port and the stacking of scraps at the scrap yard. With these two strategies, the waste of processing in the form of unnecessary double handling of scraps was reduced to the minimum.   

 

Illustration #2: Automatic Storage and Retrieval System

 

A year after Archive Singapore had implemented the Just-In-Time production system successfully it was planning to move its factory from a rented factory to its own newly built factory. The facility manager was considering the installation of the latest Automated Storage and Retrieving System (ASRS) in the company store room.

The ASRS storage system can store up to 4,000 individual items in compact tote boxes that are wheeled up and down two banks of shelves. The computer program remembers exactly what items are stored in these tote boxes and at which shelves the tote boxes are located. During retrieval, the correct items will be wheeled down from the two banks of shelves to the picking station.

A scaled down version that can store 1,000 items was priced at half a million Singapore dollars. The managing director asked for my opinion if the ASRS storage system was necessary.

Initially I was awed by the brochure selling the idea of installing such a high-technology ASRS system. But in the back of my mind I asked, “Do we really need it?”

The new assembly lines that we were going to put into the new building was designed to be so compact that tape drives were built at a one-piece-at-a-time production flow. Beside the assembly lines lay a temporary storage shelf dedicated to hold a week’s worth of the small C-items like screws and washers. The larger A-items and B-items such as the chassis of the tape drive, the stepper motors, the read-write heads, PCBAs and cardboard boxes were retrieved from the store room though a dedicated cargo lift. Once these items reached the production floor level, they were automatically rolled onto an Automated Guided Vehicle (AGV) that transports these items to the assembly line without any human handling.

The A-items and B-items were delivered to the company frequently in small quantities of half a day to two-day’s worth of supplies. These items were temporary stored in the store room. But it didn’t take up much shelf space and the number of A-items and B-items did not exceed fifty. These items could be comfortably stored in the store room.

The vendors delivered the rest of the C-items directly to the temporary storage shelf located next to the production shop floor, bypassing the store room. With this arrangement the large number of C-items was already taken care of by the vendors who made frequent deliveries of these items directly to the production shop floor. There wasn’t a need to move the C-items into the store room at all.

I told the managing director, there was no need to purchase the ASRS storage system at all. We didn’t need it. It was a complete waste of processing to move the items into the ASRS storage system and retrieve them later. The ASRS is a piece of wonderful technology but it is a shear waste of processing to move the C-items in and out of the ASRS system.

However advanced or high-technology a system is, if it injects an added waste of processing it is a foolish investment.


 

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