KR20000062157A - Production management method, design method of production line and production line - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a production line for processing a product by flowing a product through a series of processes, in which stopping of the processing apparatus in one process does not affect the other process.

Between one process and the next process, to ensure a safety WIP corresponding to the number of products which are lacking in the next process as a result of the device stopping in the one process; Between the preceding steps, an empty pallet corresponding to the number of products staying with the stop of the apparatus of the one step is facilitated.

Description

Production management method, design method of production line and production line {PRODUCTION MANAGEMENT METHOD, DESIGN METHOD OF PRODUCTION LINE AND PRODUCTION LINE}

The present invention relates to a production management method for a production line of a liquid crystal glass substrate, a PDP substrate, or a semiconductor wafer. The present invention also relates to a method for designing a production line for such a liquid crystal glass substrate, a PDP substrate, or a semiconductor wafer.

Conventionally, in the production line of a semiconductor device, the target WIP number of the self-process is determined in advance, and the deviation amount between this and the development WIP (Work In Progress) number of the self-process is calculated, and when it exceeds, the process of all processes is stopped. In some cases, Japanese Patent Laid-Open Publication No. 7-74226 proposes a method for leveling the number of WIPs in a process by reserving the process of all steps.

Moreover, the method of calculating | requiring the WIP number with respect to the required process number in each process from a regression line or an approximation curve from the data of the past WIP number and the process water is also proposed.

In addition, the production management method, which presupposes that the entire line is stopped and the device is repaired when the device is stopped and does not have a WIP for safety, is described in Nikkei Microdevices, March 1998, pp. 104-107.

Moreover, when designing and constructing a production line of a semiconductor device conventionally, the stock total number at the time of conveying the cassette (lot) of each stocker which determines the number of storage pallets installed in the stocker of each bay from a production plan ( and a method of determining the basis of the sum of the outgoing shipment totals of the inter-bay transfers are known. When the standard mentioned above may be the total number for one day by turnover (the total number of WIP of each bay / total number of lot processing in that bay in one bay), but the total number for half day There is also. In any case, the number of pallets in the stocker is determined by the ratio of the total number of from and to stockers.

On the other hand, a method of distributing and storing WIP in the vicinity of a device without having a stocker for each bay has also been proposed (Nikkei Microdevices described above).

However, in the method described in Japanese Patent Laid-Open No. 7-74226, production is performed smoothly, and in a production line in which WIP is secured as scheduled in each process, a device of a certain process is stopped for a long time due to an obstacle. In this case, the WIP does not completely decrease in the step in which the obstacle occurs, while if a series of treatments are performed in the upstream step, the WIP increases in the obstacle step beyond the target WIP number. In such a case, it is necessary to stop all the upstream processes. In addition, WIP on the downstream side becomes zero and stops. In addition, in the case where production management of such a configuration is performed, when the obstacle device is restored, it is necessary to increase the operation rate of the processing device in the previous step than usual, but if the step includes a process that cannot achieve the required operation rate, The delay in production can never be recovered.

On the other hand, in the method of obtaining the WIP number for the required number of treatments from the regression line or approximation curve from the data of the previous WIP number and the number of treatments, if the stoppage of the processing apparatus for a long time occurs, the effect of the stop affects the entire production line. can not avoid. The number of WIPs for the required number of treatments is only a sum of WIPs in process of the apparatus of the process, WIPs for processing, and WIPs for returning to the processing waiting position. When the apparatus is stopped, the actual number of WIPs is It easily exceeds the set number of WIPs.

In addition, in the production management method in which all lines are stopped when one of the production lines is stopped, all the lines are stopped by the time in which all the stop times of the devices are added, and the stop frequency and the stop time of each device are considerably improved. If not, the throughput of the production line does not improve.

Especially in the production line which produces a super large liquid crystal substrate, or the production line which produces a semiconductor wafer more than 300 mm in diameter, investment amount is also enormous, and it is difficult to install many spare apparatuses in each process. For this reason, the stopping of one apparatus completely stops the processing of one process or halves the capacity of the entire production line. Moreover, in such a production line, such as a super large liquid crystal substrate, an apparatus becomes large and the work load at the time of a malfunction or regular inspection increases, and when stopping once, it requires a very long time to recover.

As described above, in production lines such as ultra-large liquid crystal substrates, it is difficult to secure an operation rate of an apparatus or a process, and a long stoppage of the apparatus seriously affects delivery time and manufacturing cost.

By the way, this invention makes it a general subject to provide the new useful production management method and the design method of a production line which solved the said subject.

A more specific object of the present invention is to provide a production management method in which a production line of a plurality of processes does not affect the influence of an obstacle occurring in an apparatus of one process on another process.

Another object of the present invention, when designing a production line, determines the number of pallets of the stocker used to hold the WIP in a certain device in the production line based on the safety WIP number calculated from the operation history of the device. It is to provide a design method of a production line.

1 is a view for explaining a production management method according to the first embodiment of the present invention.

2 is a diagram for explaining a production management method according to a fifth embodiment of the present invention (part 1).

3 is a diagram for explaining a production management method according to a fifth embodiment of the present invention (part 2).

4 is a diagram for explaining a production management method according to a sixth embodiment of the present invention (part 1).

5 is a diagram for explaining a production management method according to a sixth embodiment of the present invention (part 2).

(Explanation of the sign)

P _i -P ₈ process

The present invention to solve the above problems

As described in claim 1,

As a production management method of a production line which includes a series of processes and performs a necessary process with respect to the said product by flowing a product in the said series of processes,

Between the one process and the next process, the number of safety WIP corresponding to the number of products which are insufficient in the next process as a result of the device stop in the one process is secured,

In addition, the production management method, characterized in that the number of empty pallets corresponding to the number of products staying with the stop of the apparatus of the one step between the one step and the step before the one step. By, or

As described in claim 2,

It includes the process group P _i (i = 1, 2 ... m) and flows a product to the said process group, and uses the apparatus group E _j (j = 1, 2 ... n) with respect to the said product. As a production management method of the production line that performs the necessary processing,

A process P _i to the following step between P _{i + 1,} as a result of the stop device of the process P _i to be safe WIP corresponding to the number of products that are insufficient in the step P _{i + 1} of

The processing capabilities of the process P _i of the device E _j T _ij, by the use of the ratio for process P _i of the device E _j to R _ij, process P _i throughput T _Ri

Saved by

With the reference treatment capacity of step P _i as T _i , the unit number C _EPi of step P _i

Saved by

By the need to be treated per day in the production planning phase process P _i N _i, U _d in others responsible utilization, the process P _i of the required equipment number C _ENi

C _ENi = N _i / (T _i ㆍ U _d / 100)

Saved by

A product number missing in the subsequent step when the device E _j a O _fj in the stop

_{S ij = {C ENi - (} C EPi R ij and _{T ij / T i)} T} i × O fj × U d / 100

To obtain by, and obtained according to the up to _{S i (S i = Max (} S ij, j = 1, 2 and and and n) of the above S _ij,

In addition, by the production management method characterized in that the number of empty pallets corresponding to the S _i is secured immediately before the step P _i , or

As described in claim 3,

The number of the empty pallets is determined according to 100S _i / B _i with the yield of the process P _i as B _i , or by the production management method according to claim 2, or

As described in claim 4,

The production management method according to claim 2 or 3, wherein the use ratio R _ji of the apparatus is determined to minimize the safety WIP number S _i in a range satisfying the processing capacity T _Ri required in the process P _i . By, or

As described in claim 5,

The production period according to claim 2 or 3, characterized in that the stop period O _fj is longer between the planned offline time and the unplanned offline time defined in SEMI E10-96 standard, or

As described in claim 6,

The stop period O _fj is the mean MTUO of off-plan off-line time, the average out-of-plan downtime interval MTUD, and the management period P days of the amount of production in the production plan, k being the reliability of the mean failure interval specified in the SEMI E10-96 standard. As the lower limit of,

O _fj (day) = MTUOln (P / (kMTUD)}

Obtained by the production management method of claim 2 or 3, or

As described in claim 7,

_Production of the process P _i by the device group E _j (j = 1, 2... N), and the processing of the next step P _{i + 1} by the device group E _k (k = 1, 2 ... m). As a production control method of a line, when the safety WIP cannot be set between the process P _i and the process P _{i + 1} , the virtual process P _{i, i + 1} and the virtual device E _{j, k} are defined and the virtual process Set the safety WIP number for P _{i, i + 1} .

The use ratio of the virtual device E _j, the virtual process in _k P _i, the processing power of the _{i + 1} T _{j, k,} virtual device E _j, the virtual process P _{i, i + 1} of the _k R _{j, Let k} be the processing capacity T _{Ri, i + 1} of the virtual process P _{i , i + 1} .

Saved by

Let the reference processing capacity of the virtual process P _{i + 1 be} T _{i, i + 1} and the number of devices C _{EPi, i + 1} of the virtual process P _{i, i + 1}

Saved by

A production schedule wherein the virtual process, P _i, by a per day need be processed in the _{i + 1} to N _{i, i + 1,} U _d to the other responsible utilization rate, wherein the virtual process P _i, required equipment number of the _{i + 1} C _{ENi , i + 1}

C _{ENi, i + 1} = N _{i, i + 1} / (T _{i, i + 1} ㆍ U _d / 100)

To obtain by, a product number S _jO lacking in the next step when the device E _j a O _f in the stop

If the device E _k is stopped at O _f days, the number of products insufficient in the next step S _Ok

To obtain by, and secured in accordance with the S to the largest of _{jO Ok} S _i and _{S, i + 1} (S _{i, i + 1} = Max _(jO S, S _Ok)),

In addition _{, according} to the production management method, immediately before the step P _i , the number of empty pallets corresponding to S _{i, i + 1} is ensured.

As described in claim 8,

In a production line including a series of processes and processing a product by flowing a product in the series of processes, between the one step and the next step, the following A product that secures a safety WIP number S _i corresponding to the number of products that are lacking in the process, and which remains between the one process and the process before the one process with the stop of the apparatus of the one process. As a production management method to secure the number of empty pallets corresponding to the number of

To the minimum number of safety WIP required to handle the processing number N _i necessary per day for each step i to the basic WIP number S _ki, can WIP plan of steps i S _Hi be the safety WIP S _i and the base Equation as sum of WIP number S _ki

S _Hi = S _i + S _ki

To obtain by, at that time, the safety WIP number S _i to the reference constant K _i is the planned value divides the WIP number S _Hi to the required processing can be N _i S _Hi / N _i, and set to be the same as the above-mentioned step i By the production management method characterized in that, or

As described in claim 9,

Process product P _i (i = 1, 2... M) is processed to the product by using device group E _j (j = 1, 2 ... n) by flowing the product through the process group. As a production management method of the production line which performs

Device E _j can WIP of the process the product can be in process at S _Pj, device E _j stored pallet handling the treated air WIP the number of products in the atmosphere in the S _Wj, products and to terminate the processing of the device E _j atmospheric release of The number of products waiting to be returned to WIP number S _Fj and apparatus E _j to be carried out is set to the waiting number of WIP numbers S _Tj to be returned, and the use ratio of the apparatus E _j of process P _i is set to R _ij , and each process is required. With the operation rate U _i , the basic WIP number S _ki of the process P _i is

And define the planned WIP number S _Hi of each process i as the sum of the basic WIP number S _Ki and the safety WIP number S _i .

S _Hi = S _Ki + S _i

To be defined as,

The reference constant K _i of the step i defined by dividing the planned WIP number S _Hi by the number of treatments N _i per day required in the step i is set to ensure the desired value as the safety WIP number S _i . By a production management method, or

As described in claim 10,

As a production management method of a production line which includes a series of processes and performs a required process for the product by flowing a product in the series of processes,

Between the one process and the next process, the number of safety WIP corresponding to the number of products which are insufficient in the next process as a result of the device stop in the one process is secured,

And securing a number of empty pallets corresponding to the number of products staying with the stop of the apparatus of the one process, between the one process and the process before the one process,

Immediately after each step, empty pallets for WIP are prepared immediately after the same number as the safe WIP number, and just before each process, empty pallets with the same number as the safe WIP number are prepared,

Maximizing the operation rate of the process when a failure occurs in the process, and further comprising the step of transferring the immediately preceding WIP in the immediately empty WIP pallet to the empty pallet for WIP immediately after the above, or

As described in claim 11,

When a failure occurs in the above step, the production control method according to claim 10, further comprising the step of transferring the WIP to the empty pallet for the straight line WIP immediately after the occurrence, or

As described in claim 12,

As a production management method of a production line including a series of processes and processing a product by flowing a product in the series of processes,

Between the one process and the next process, the number of safety WIP corresponding to the number of products which are insufficient in the next process as a result of the device stop in the one process is secured,

Also, between the one step and the step before the one step, a number of empty pallets corresponding to the number of products staying with the stop of the apparatus of the one step is secured,

The planned WIP number defined by the sum of the safety WIP number and the basic WIP number in each process is compared with the actual performance WIP number, and when the performance WIP number is less than the planned WIP number, the WIP is recalled from the upstream process. By a production control method characterized by moving to a process, or

As described in claim 13,

The production WIP number is a sum of the WIP number immediately after the step and the immediately preceding WIP staying just before the step when the step is stopped, or

As described in claim 14,

When the apparatus is stopped in the one step, the WIP immediately after the previous step of the one step is changed to the WIP just before the one step;

As described in claim 15,

It includes the process group P _i (i = 1, 2 ... m), and flows a product to the said process group, and uses the apparatus group E _j (j = 1, 2 ... n) with respect to the said product. As a design method of the production line which performs the required processing,

A process P _i to the following step between P _{i + 1,} as a result of the stop device of the process P _i to be safe WIP corresponding to the number of products that are insufficient in the step P _{i + 1} of

To the processing capabilities of the apparatus for the process P _i E _j using the ratio of the T _ij, the process P _i of the device E _j to R _ij, the processing capabilities of the process P _i T _Ri

Saved by

With the reference treatment capacity of step P _i as T _i , the unit number C _EPi of step P _i

The required number of devices C _ENi in the process P _i is determined by calculating the required number of processes per day in the process P _i as N _i and U _d as the responsible operation rate.

C _ENi = N _i / (T _i ㆍ U _d / 100)

Saved by

A product number missing in the subsequent step when the device E _j a O _fj in the stop

_{S ij = {C ENi - (} C EPi R ij and _{T ij / T i)} T} i × O fj × U d / 100

Saved by

By the method of designing a production line, characterized in that to obtain, depending on that of the maximum of the _{S ij S i (S i =} Max (S ij, j = 1, 2 and and and n), or

As described in claim 16,

_Production of the process P _i by the device group E _j (j = 1, 2... N), and the processing of the next step P _{i + 1} by the device group E _k (k = 1, 2 ... m). As a design method of the line, when the safety WIP cannot be set between the process P _i and the process P _{i + 1} , the virtual process P _{i, i + 1} and the virtual device E _{j, k} are defined and the virtual process P _{i, i + 1} for safety WIP

The use ratio of the virtual device E _j, the virtual process in _k P _i, the processing power of the _{i + 1} T _{j, k,} virtual device E _j, the virtual process P _{i, i + 1} of the _k R _{j, Let k} be the processing capacity T _{Ri, i + 1} of the virtual process P _{i , i + 1} .

Saved by

Let the reference processing capacity of the virtual process P _{i + 1 be} T _{i, i + 1} and the number of devices C _{EPi, i + 1} of the virtual process P _{i, i + 1}

To obtain by, by the production plan on the virtual process P _i, the treatment required per day in the _{i + 1} N _{i, i + 1,} U _d to the other responsible utilization, requires the device of the virtual process P _{i, i + 1} Logarithm C _{ENi, i + 1}

C _{ENi, i + 1} = N _{i, i + 1} / (T _{i, i + 1} ㆍ U _d / 100)

To obtain by, a product number S _jO lacking in the next step when the device E _j a O _f in the stop

If the device E _k is stopped at O _f days, the number of products insufficient in the next step S _Ok

To obtain by, the method of designing a production line, characterized in that the securing according to one maximum of the above S _jO and _{S Ok S i, i + 1} (S i, i + 1 = Max (S jO, S Ok)) By, or

As described in claim 17,

It includes the process group P _i (i = 1, 2 ... m), and flows a product to the said process group, and uses the apparatus group E _j (j = 1, 2 ... n) with respect to the said product. As a design method of the production line which performs processing,

Device for WIP number of handles serial number of the processing in the E _j S _Pj, device E _j can process the product can be in waiting to be processed from the storage pallet waiting WIP for export to exit the S _Wj, processing of device E _j atmosphere The number of products waiting to be transported is S _Fj and the number of products waiting to be returned to the device E _{j is the} number of products waiting to be transported is S _Tj , and the use ratio of the device E _{j in} the process P _i is Rij, By setting the required operating rate of each process as U _i , the basic WIP number S _Hi of the process P _i is

And the planned WIP number S _Hi of each process i as the sum of the basic WIP number S _ki and the safety WIP number S _i .

S _Hi = S _ki + S _i

To be defined as,

Dividing the planned WIP number S _Hi by the number of treatments N _i per day required in the step i, and setting the standard schedule K _i of the step i defined as the safety WIP number S _i to ensure a desired value. By the design method of the production line characterized by

As described in claim 18,

Process product P _i (1 = 1, 2... M), and the product was flowed through the process group, thereby using the apparatus group E _j (j = 1, 2. As a production line that performs the necessary processing,

Having one of the process P _i to the same empty pallets between the next process P _{i + 1} of, as a result of the device is stopped in the step P _i and a number of safety WIP corresponding to the number of products that are insufficient in the step P _{i + 1} and,

Immediately before the one process P _i, an empty pallet equal to the safety WIP number is provided,

The safety WIP number is

The processing capabilities of the process P _i of the device E _j T _ij, by the use of the ratio for process P _i of the device E _j to R _ij, process P _i throughput T _Ri

Saved by

With the reference treatment capacity of step P _i as T _i , the unit number C _EPi of step P _i is

Saved by

By the need to be treated per day in the production planning phase process P _i N _i, U _d responsibility to others operating rate, the required number C _ENi device of the process P _i

C _ENi = N _i / (T _i ㆍ U _d / 100)

Saved by

A product number missing in the subsequent step when the device E _j a O _fj in the stop

_{S ij = {C ENi - (} C EPi R ij and _{T ij / T i)} T} i × O fj × U d / 100

To obtain by, by the production line, it characterized in that it is set such that the S _ij up to _{S i (S i = Max (} S ij, j = 1, 2 and and and n) of the, or

As described in claim 19,

Process the device group to _{P i E j (j = 1} , 2 and and and n) is processed, and then the process P _{i + 1} the device group E _{k (k} = 1, 2 and and and m) is processed, and At this time, as a production line that can not establish a safety WIP between the process P _i and the process P _{i +1} ,

Between the process P _{i + 1} and the next process P _{i + 2} a, as a result of the device suspended in the process P _i to the same empty pallets to the number of the safety WIP corresponding to the number of products that are insufficient in the step P _{i + 1} Equipped,

Immediately before the one step P _i, an empty pallet equal to the safety WIP number is provided,

The safety WIP number is

Virtual process P _{i, i + 1} and virtual device E _{j, k} are defined, and for the virtual process P _{i, i + 1} ,

The use ratio of the virtual device E _j, the virtual process in _k P _i, the processing power of the _{i + 1} T _{j, k,} virtual device E _j, the virtual process P _{i, i + 1} of the _k R _{j, Let k} be the processing capacity T _{Ri, i + 1} of the virtual process P _{i , i + 1} .

It is obtained by and the reference processing capacity of the virtual process P _{i + 1} is T _{i, i + 1} , and the device number C _{EPi, i + 1} of the virtual process P _{i, i + 1} is _obtained.

Saved by

A production schedule wherein the virtual process, P _i, by a per day need be processed in the _{i + 1} to N _{i, i + 1,} U _d to the other responsible utilization rate, wherein the virtual process P _i, required equipment number of the _{i + 1} C _{ENi , i + 1}

C _{ENi, i + 1} = N _{i, i + 1} / (T _{i, i + 1} ㆍ U _d / 100)

Saved by

A product number S _jO lacking in the next step when the device E _j a O _f in the stop

Saved by

If the device E _k has stopped O _f one day, the number of products insufficient in the next step S _Ok

_Obtained by the production line characterized in that it is determined according to the maximum of S _jO and S _Ok S _{i, i + 1} (S _{i, i + 1} = Max (S _jO , S _Ok )). , or

As described in claim 20,

In a production line with a plurality of bays,

Each bay has a stocker,

By a production line characterized in that the number of pallets of the stocker of each bay is stored so as to accommodate at least the total number of safety WIPs of all processes belonging to the bay, or

As described in claim 21,

Wherein, in each process P _i, in the case where limited by the type of products that are processed by the process P _i for the use of the device E _j will be charged, the process group P _{i (i} = 1, 2 and and and m) Instead, the process varieties Pi (i = 1, 2 ... z), which are subdivided into the process group by product type, are defined, and the safety of each of the process varieties included in the process variety group P _i It solves by the production control method of Claim 2 including the process of calculating a WIP and a basic WIP.

[Action]

In the present invention, a WIP corresponding to the number of safe WIPs is secured so as not to affect the long-term stoppage of the apparatus of the process immediately after the process, and just before, the same number of empty pallets are secured. . When a long time stop occurs, the WIP is immediately processed and reduced in the next step, and at the same time, almost the same number of WIPs as before are retained. By managing the production line so that the sum of the immediately following WIP and the immediately preceding WIP is substantially constant even during normal operation and long time stop of the device, the long stop of the device does not affect other processes. On the other hand, conventionally, since only the last WIP was considered, when an apparatus stops for a long time, WIP will increase and a production line will stop. On the other hand, in the present invention, the management is performed by comparing the number of plans and the number of achievements with respect to the sum of the immediately preceding WIP and the immediately following WIP, so that the line does not need to be stopped, and the effect of the device stop is affected only by the process in which the device stop occurs. It becomes possible to absorb.

The present invention also provides a method for calculating the safety WIP number from operating performance data of the apparatus. This method makes it possible to clearly define the planned WIP number as compared with the method of approximating the safety WIP number from the trend of WIP and treated water. In the present invention, the number of pallets of the stocker required is determined by calculating the safety WIP number. This facilitates the required number of pallets when needed, avoids the stopping of a device in another process in another process in the production line, and improves the throughput of the production line. In addition, in the present invention, unnecessary pallets are not installed, thereby minimizing the cost of the stocker.

(Example of the invention)

(First embodiment)

A case where the present invention is applied to the manufacture of a TFT substrate constituting a liquid crystal display device will be described with reference to FIG.

Referring to Fig. 1, the production line of the TFT substrate includes steps P ₁ to P ₉ , and devices E ₁ to E ₄ are processing steps P ₂ , P ₅ and P ₈ . Among them, the above-mentioned step P ₂ is a process unit E ₁ and E _2, and the other hand, in the step P ₅ is used, the entire of the device E ₁ ~ E _4. In Fig 1, a process P _1, P _4, P ₇ correspond to the film-forming step, and the process P _2, P ₅ and P ₈ correspond to the photo process, and P _3, the etching step P _6, P _9. The TFT substrate is processed by sequentially processing the processes P ₁ to P ₉ .

In this embodiment, the processing capacity of each step is determined by determining the load ratio of each step and determining the usage ratio of each device so as to be the same. It also maximizes the capacity of the manufacturing line by determining the appropriate number of planned WIPs (safety WIP and basic WIP).

First, the processing capacity T _Ri of each process is calculated as follows using the ratio of the device E _j to the process P _i as R _ij and the processing capacity of the device E _j as T _ij .

T _R2 = R ₂₁ ㆍ T ₂₁ ㆍ R ₂₂ ㆍ T ₂₂

T _R5 = R ₅₁ ㆍ T ₅₁ ㆍ R ₅₂ ㆍ T ₅₂ ㆍ R ₅₃ ㆍ T ₅₃ ㆍ R ₅₄ ㆍ T ₅₄

T _R8 = R ₈₃ ㆍ T ₈₃ ㆍ R ₈₁ ㆍ T ₈₁

In addition to the load rate of each process P _i to L _i, another person responsible for utilization in U _d, the required substrate processing number N _i

N _i [day / day] = [Number of required treatments in production plan of process P _i ] / [working days in month]

If defined as, the load factor L _i of each process can be calculated by the following equation.

L ₂ = N ₂ / [T _R2 × U _d2 / 100]

L ₅ = N ₅ / [T _R5 × U _d5 / 100]

L ₈ = N ₈ / [T _R8 × U _d8 / 100]

Where L ₂ = L ₅ = L ₈ , in other words, the ratio of the use of the device E _ij R ₂₁ , R ₂₂ , R ₅₁ , R ₅₂ , R ₅₃ , R ₅₄ , R ₈₃ , R ₈₁ so that the load factor of each process is equalized. Determine. This finds the optimal use ratio of the device to maximize the throughput of the manufacturing line.

Here, reference processing capacity T _i [piece / day] of process P _i

Let T _i = Max (T _ij , j = 1, 2... M),

A device number C _EPi of the process P _i

And the number of required devices in the process P _i

C _ENi = N _i ㆍ (T _i ㆍ U _d / 100) [Large]

Defined as

Then, when the unit period is E _ij O _fj [one] may lack substrate in the next process when a stop S _ij, in other words be a substrate staying in a front-end S _ij is

_{S ij = {C ENi - (} C EPi R ij and _{T ij / T i)} T} i × O fj × U d / 100

Can be calculated as However, the period O _fj is the longest device downtime expected within the production plan's management period (usually around one month).

The largest quantity S _i , i.e., S _i = Max (S _ij , j = 1, 2... N) among the number of substrates S _ij for each device of j = 1, 2. Is the safe WIP number of process P _i .

Immediately after the step P _i , the production line is managed so as to secure a WIP corresponding to an integer indicating the total number of the safety WIP number S _i or the closest lot knitted substrate number closest thereto. In addition to the yield of the process P _i to B _i on the eve of the process P _i, S corresponding to the _i / B _i × 100, or which one corresponds to an integer indicating the total number of the nearest pilot knitted substrate blank in Secure pallets.

As a result of the management of this production line, the effect of the device shutdown of the process P _i on other processes is avoided, and the production throughput is maximized.

Second Embodiment

The following examples to the WIP easy pharmaceutical processing of P _s and P _n step process to stay on will be described with the management method of the number of WIP after safe WIP, equipment stop, and returns to a second embodiment of the present invention.

Due to the severe time constraints between the P _s process and the P _n process, inline handling is necessary. Table 1 shows the processing capacity of each device of the P _s process and the P _n process.

First, calculate the off-hours of the longest plan. At that time, the MTBF is corrected by a coefficient of reliability of 90%,

O _f (E ₁ , out of plan) = 2701n [1440 × 30 / (14118 × 0.634)] = 425 [min]

O _f (E ₂ , out of plan) = 1801n [1440 × 30 / (9792 × 0.66)] = 338 [min]

O _f (E ₁₀ , out of plan) = 6901n [1440 × 30 / (25260 × 0.539)] = 797 [min]

Get

Among these, the longest plan shown in Table 1 has the long side as the longest stop time of each device compared with the off-line time.

The P _s process is treated in one E ₁₀ , and the P _n process is treated in two E ₁ and E ₂ . If the process grace time from the end of the processing of the P _s process to loading into the device of the P _n process is within 40 [min], no safety WIP can be established between the two processes. Thus E ₁ and E ₂ are virtual devices in series with E ₁₀ and need to calculate their capabilities.

Assume that E ₁₁ is a continuous device E ₁₀ and device E ₁ , the throughput is T ₁₁ [pieces / day], and the failure rate is F ₁₁ . A virtual device in which device E ₁₀ and device E ₂ are continuous is represented by E ₁₂ , its throughput is T ₁₂ [day / day], and the failure rate is represented by F ₁₂ . Since the throughput of E ₁₀ of the continuous moving greater than the sum of the throughput of the E ₁ and E _2, E _11, E ₁₂ at the time of continuous operation of the tact is the same as for E ₁ and E ₂ tact. Non-failure rate (1-F ₁₁₎ of the device E ₁₁ is given by the product (1-F ₁₀₎ and _(1-F 1) of the non-failure rate of each device (E ₁₀ and E _1). In addition, it is assumed that the auxiliary working time is obtained by subtracting the simultaneous working time of each device by adding the auxiliary working time of each device, and T ₁₁ and T ₁₂ can be calculated by the following equation (assuming that the auxiliary work is performed independently. ).

T ₁₁ = (86 400 x 0.981 x 0.973- (116.4 + 6.4) x 60} / 81 = 927

[Per day]

T ₁₂ = (86400 × 0.982 × 0.973- (51.4 + 6.4) × 60} / (338 + 51.7) = 203

[Per day]

Also for the process, consider a virtual process P _{sn in} which the process P _s and the process P _n are continuous. The utilization ratios R ₁₁ and R ₁₂ of the virtual devices E ₁₁ and E ₁₂ for this process are both 1. The processing capacity of the virtual process P _sn is T _{R, sn} , the number of devices is C _{EP, sn} , the number of filling devices is C _{EN, sn} , and the load factor is L _sn .

T _{R, sn} = R ₁₁ ㆍ T ₁₁ + R ₁₂ ㆍ T ₁₂ = 1130 [pcs / day]

The device log number C _{EP, sn} in the process P _s is a reference treatment capacity T _sn ,

T _sn = Max (T ₁₁ , T ₁₂ ) = T ₁₁ = 927 [pcs / day] (1)

C _{EP, sn} = R ₁₁ ㆍ T ₁₁ + R ₁₂ ㆍ T ₁₂ / T ₁₁

= 927/927 + 203/927 = 1.219 [large] (2)

May 27 000 the number of the party pilyong treatment [number / general, when a process other charge 30 the working days of the month day, utilization U _d to 90%, a treatment number per day pilyong in the step P _sn virtual N _sn is 900 [ Days / day,

C _{EN, sn} = N _sn / (T ₁₁ ㆍ U _d / 100)

= 900 / (927, 0.9) = 1.079 [large] (3)

The safety WIP is calculated for the virtual process P _sn at the time of stopping the devices of the devices E ₁₀ , E ₁ , and E ₂ . In fact, the WIP equivalent to the safety WIP number S _s immediately after the P _n process is regarded as a safety WIP for both P _s and P _n processes.

[E ₁₀ stop] Safety WIP S ₁₀

S ₁₀ = {C _{EN, sn-} (C _{EP, sn} -R ₁₁ ㆍ T ₁₁ / T ₁₁ -R ₁₂ ㆍ T ₁₂ / T ₁₁ )}

T ₁₁ O _f (spin slide) 0.9 = {1.079 (1.219-1-0.219)} 927 N (O _f /1440)0.9=0.6251 O _f = 0.6251797 = 498.2

[E ₁ stop] Safety WIP S ₁

S ₁ = {1.079 (1.219-1)} 927 (O _f /1440)0.9

= 0.4983 O _f = 0.4983,1050 = 523.2 [piece]

[E ₂ stop] Safety WIP S ₂

S ₂ = {1.079- (1.219-0.219)} 927. (360/1440) 0.9

= 0.0458 O _f = 0.0458 ・ 360 = 16.5 [pcs]

The above results show that the stopping of E ₂ has no effect, but the effects of stopping of E ₁ and E ₁₀ are about the same, and the safety WIP is required to be 523 [pieces], about 26 [lots]. In other words, 26 [lots] of WIPs are required immediately after the P _n process, and 26 pallets of empty pallets are required immediately before the P _s process.

Third Embodiment

Next, one example of basic WIP calculation is shown for the virtual process P _sn of Example 1. FIG. Table 2 shows the basic data of each device for calculation.

Table 3 also shows the calculation results of the basic WIP of the virtual devices E ₁₁ and E ₁₂ and the virtual process P _sn .

As for the virtual device, the processing wait WIP S _{W, 10} of the entrance device E ₁₀ and the return waiting WIP S _{T, 10} of the two consecutive devices are S _{W, 11} (S _{W, 12} ) of the virtual device E ₁₁ (E ₁₂ ). ), S _{T, 11} (S _{T, 12} ). Let the export standby WIP S _{F, 01} (S _{F, 02} ) of the exit device E ₁ (E ₂ ) be S _{F, 11} (S _{F, 12} ) of the virtual device E ₁₁ (E ₁₂ ). In addition, WIP S _{P, 10} during the processing of the inlet device E ₁₀ , WIP S _{P, 10 for} carrying out and WIP S _{W, 01} (S _{W, 02} ) during the processing of the WIP S _{P, 10} and the outlet E ₁ (E ₂ ), WIP during the processing Add S _{P, 01} (S _{P, 02} ) to S _{P, 11} (S _{P, 12} ) of the virtual device.

For the virtual process P _sn , since the entrance device E ₁₀ of the virtual devices E ₁₁ and E ₁₂ are common, from the sum of the respective WIP numbers (during processing, processing waiting, carrying out waiting, and return waiting) of E ₁₁ and E ₁₂ , Subtracting the number of common WIPs from E ₁₁ and E ₁₂ was used as each WIP number of P _sn (during processing, waiting for carrying out, waiting for carrying out, return waiting).

The required operation rate U _sn of P _sn is assumed to be 90% of the process others' responsibility,

U _sn = 90 · C _{EN, sn} / C _{EP, sn} = 90 · 1.079 / 1219 = 79.66 [%] (4)

The failure rate as a whole (1-F _sn ) takes the average of the failure rates of the virtual devices E ₁₁ and E ₁₂ .

(1-F _sn ) = (0.981 × 0.973 + 0.982 × 0.973) /2=0.955

Therefore, the basic WIP S _{k, sn} of the virtual process P _sn can be calculated by the following equation.

S _{k, sn} = 0.7966 x (7 + 1 + 2 + 1) x 0.955 = 11 x 0.7608 = 8.4 [lots] (5)

Fourth Embodiment

Next, the first embodiment in which the basic schedule of the process is calculated from the safety WIP and the basic WIP is shown in the case of the second and third embodiments. The WIP of the virtual process that combines the P _s process and the P _n process has a basic WIP of 8.4 [lots] and a safe WIP of 26 [lots]. The required number of treatment lots per day is 900 [pieces / day] divided by 20 [pieces / lot] and 45 [lots / day], so the standard schedule K _sn can be calculated by the following equation.

K _sn = 8.4 / 45 + 26/45 = 0.1867 + 0.5778 = 0.7644 [day]

P _s and P _n the process step with the safety WIP, by the calendar as the reference constant 0.7644 [one], it is possible to prevent the influence of device stops for a long time on the other step.

[Example 5]

Next, a method of managing schedules according to actual subsequent steps based on the safety WIP and the basic WIP will be described with reference to FIG. 2 as a fifth embodiment of the present invention.

2 shows the planned WIP before and after the P _sn process. The basic WIP S _{k, sn} of the P _sn process is equal to the sum S _{T, sn} + S _{W, sn} + S _{P, sn} + S _{F, sn} of each of the WIPs in the waiting for waiting, processing, waiting, and carrying out process. The reference schedule of the P _sn process is given as the sum of the schedule corresponding to this basic WIP and the schedule corresponding to the safety WIP. The status of each lot is (… → [Pre-process basic WIP]) → [Pre-process safety WIP] → [P- _sn process basic WIP] → [P- _sn process safety WIP] → [Follow-up process basic WIP] → [Follow-up process safety WIP →… The process proceeds by moving to].

Fig. 3 shows the results WIP that can be actually monitored (collected) on the process management system of the development. The performance WIPs that can be collected are the WIP during the processing of each process (operation) in the process control system and the WIP for processing. The performance WIP corresponding to the basic WIP and safety WIP of FIG. 2 can be calculated from these in-process and waiting-waiting WIPs.

Performance WIP, S _{Z, sn} corresponding to the basic WIP number S _{k, sn} of P _sn process is ((WIP S _{Z, s11} during P _s process) + (P _n process waiting WIP S _{Z, n + 0} ) It can be calculated as + (WIP S _{Z, n + 1} ) +1} during P _n process. Schedule management so that S _{Z, sn} matches the default WIP number S _{K, sn} . 1 is added because the performance value S _{Z, sn} does not include the return waiting WIP S _{T, sn} of the P _sn process. S _{Z, sn} is called WIP during the process P _sn .

The WIP, S _{Z, sna} corresponding to the safety WIP number S _sn of the P _sn process can be calculated as {(WIP S _{Z, aso} ) 1}. S _{Z, sna} is called WIP immediately after the process P _sn .

Safety of the previous process P _sr of the P _s process WIP, S _{z, sra} corresponding to the safety WIP S _sr is {(P _s process WIP S _{Z, s10} ) -1}. S _{Z, sra} is called WIP immediately after step P _sr .

(S _sn -S _{Z, sna} ) When ≥20 (if there is a space of 1 [lot] for WIP S _{Z, sna} immediately after the P _sn process for safe WIP S _sn ), WIP during the processing of the P _sn process 1 [lot] is advanced from S _{Z, sn} and input to WIP S _{Z, sna} immediately after the P _sn process.

Similarly, (S _k, S _{Z sn, sn)} If a ≥20 (P _sn the WIP S _{Z, sn} of the process of the step with respect to the basic WIP S _{k, sn,} 1 [lot] saenggimyeon over a blank area) P _sr process Immediately after WIP S _{z, sra} , 1 [lot] can be _advanced to the P _sn (slide etch) process and input to WIP S _{Z, s n} during the processing of the P _sn process.

In general, the process P _i of the safety WIP (plan) S _i and the process P _i immediately WIP (Performance) S _{z, ia,} the process P _i basic WIP (plan) S _{k, i} and WIP (Performance) S _z of the process of the _by comparing the _i in turn, to make sure that one [Lot]-minute blank area is looking for a plan WIP earnings WIP, the status of the lot [P _i-1] of the process of WIP → P _i process immediately after the process WIP → P _i in the process of processing WIP → P _i goes process proceeds sequentially transferred as directly after the WIP. In this way, lot progression by a subsequent process becomes possible.

[Example 6]

Next, using the P _sn process as an example, a schedule management method in the case where a long stop occurs actually in the apparatus will be described. E ₁₀ in the device it is assumed that a fault occurs in the still 800 [min].

4 shows the planned WIP (safety WIP and basic WIP) and empty pallets before and after the P _sn process. The empty pallet is for storing a lot which stays just before the process when the apparatus is stopped for a long time, and is equal to the number of safe WIPs divided by the number 20 of the basic knitting of the lot. 5 shows the results of the results WIP before and after the P _sn process when the device is stopped for a long time.

E _{10 The} process of the P _sn process is stopped while the device is stopped. Processes other than the P _sn process are processed as planned. Processing of subsequent steps in the process of P _sn WIP S _Z, whenever an empty area on the default WIP S _k.as to _as, immediately after the P _sn process WIP S _Z, the status of the lot _sna S _{Z, as} Move.

On the other hand, during the process of the P _sn process, the status of the conveyance table and the processing table 2 [lots] of the WIP S _{Z and sn} does not change while the apparatus is stopped. The status of 9 lots of the remaining processing and waiting to be taken out is transferred to WIP S _{Z, sna} immediately after the P _sn process. Therefore, WIP S _{Z, sn} becomes 2 [lots] during the P _sn process. After that, since _{SIP, sna} cannot be replenished immediately after processing from WIP S _{Z, sn} , S _{Z, sna} decreases.

Just before the P _sn process, an empty pallet with the same number of safe WIPs is prepared. During the long stop of the device _{, the} lot is transferred from the WIP S _{Z, sna} immediately after the previous step P _sr to this empty pallet. The WIP housed in the empty pallet is called WIP just before P _sn process, and is represented by S _{Z, snb} .

Until immediately after the step P _sn WIP S _{Z, snb} be the same as the safety WIP number S of P _{sn sn} process, S _Z, it goes transferred to S _Z, the status of the lot from the _{snb sra.} Moving timing of the processing of the next step of the P _sn process WIP S _Z, at the timing generated a blank area for the basic WIP S _{k, as} a _as, P _sn processes the status of the WIP S _Z, a _sna lot S _Z immediately after the _{You can do this with the} same timing _as with _.as . This allows production to continue after the subsequent process as a whole without being affected by the P _sn process shutdown.

However, if S _{Z. snb ≥} S _sn (when the number of previous _WIPs exceeds the number of safe _WIPs ), the entire line is stopped. In practice, since S _sn is set to be the longest expected stop time, the stop of the entire line will not occur in principle.

After 800 [min], the sum of WIP and WIP during processing immediately after the P _sn process, [S _{Z, sna} + S _{Z, sn} ], decreases by 500 [pieces] and 25 [lots] until the E ₁₀ device is restored. . In reality, immediately after WIP S _{Z, sna} decreases by 16 [lots] to 10 [lots], and during processing of the P _sn process, WIP S _{Z, sn} decreases by 9 [lots] to 2 [lots]. And just before the P _sn process, WIP S _{Z, snb} is increasing from 0 [lot] to 25 [lot].

[Example 7]

An embodiment of a method for recovering a reduced WIP to a safe WIP number after a previous long device shutdown recovery is shown. In Example 6, after the recovery of the V ₆ and E ₁₀ devices, it is necessary to recover the required WIP number by making the operation rate of the process higher than usual at P _s . That is _, the 25 [lot] status of WIP S _{Z, snb} immediately before the P _sn process may be _transferred to WIP S _{Z, sna} immediately after _passing through WIP S _{Z, sn} during processing. Naturally, we can afford to handle 900 [pieces / day] needed to keep the entire line running.

Here, the recovery time is calculated when the operation rate of the P _sn process is increased to 100%. The required operation rate of the P _sn process is 80% by Equation (4), and the affordability is 20%. The number of WIPs to be recovered is 500 [pcs], the standard processing capacity of the P _sn process is (1) by T _sn = 927 [pcs / day], and the number of devices is (2) by C _{EP, sn} = 1.219 [set ]Because of,

K = 500 / {1.219.927 (1-80 / 100)} = 2.21 [day] (6)

Therefore, from about 2.2 [day], the number of WIP S _{z, sna} immediately after the P _sn process can be recovered to the number of safe WIP 523 [pieces].

As mentioned above, although this invention was demonstrated about the preferable Example, this invention is not limited to said Example, A various deformation | transformation and a change are possible within the summary described in a claim.

According to a feature of the present invention as described in claims 1 to 21, a WIP corresponding to the number of safe WIPs is secured so as not to affect the long-term stop of the apparatus of the process for a long time immediately after the process. And leave almost equal number of empty palettes. In this way, when the stoppage of the apparatus for a long time has occurred, the WIP is processed and reduced immediately in the next step, and at the same time, almost the same number of WIPs as the input stage remain. At that time, by managing the production line such that the sum of the immediately following WIP and the immediately preceding WIP is substantially constant even at the time of the long time stop of the apparatus in the usual time, the long time stop of the apparatus can be avoided from affecting other processes. In other words, in the present invention, the management is performed by comparing the planned number and the actual number of the sum of the immediately preceding WIP and the immediately following WIP, so that the line does not need to be stopped, and the influence of the device stop is absorbed only by the process in which the device stop occurs. It becomes possible.

The present invention also provides a method for calculating the safety WIP number from operating performance data of the apparatus. This method makes it possible to clearly define the planned WIP number as compared with the method of approximating the safety WIP number from the trend of WIP and treated water. In the present invention, the number of pallets of the stocker required is determined by calculating the number of the safety WIP. By doing so, the required number of pallets is serviced when necessary, and the stopping of a device in another process in one process in the production line is avoided in another process, and the throughput of the production line is improved. In addition, in the present invention, unnecessary pallets are not installed, thereby minimizing the cost of the stocker.

Claims (21)

As a production management method of a production line which includes a series of processes and performs a necessary process with respect to the said product by flowing a product in the said series of processes, Between the one process and the next process, the number of safety WIP corresponding to the number of products which are insufficient in the next process as a result of the device stop in the one process is secured, And between the one step and a step before the one step, a number of empty pallets corresponding to the number of products staying with the stop of the apparatus of the one step is secured. It includes the process group P _i (i = 1, 2 ... m) and flows a product to the said process group, and uses the apparatus group E _j (j = 1, 2 ... n) with respect to the said product. As a production management method of the production line that performs the necessary processing, A process P _i to the following step between P _{i + 1,} as a result of the stop device of the process P _i to be safe WIP corresponding to the number of products that are insufficient in the step P _{i + 1} of The processing capabilities of the process P _i of the device E _j T _ij, by the use of the ratio for process P _i of the device E _j to R _ij, process P _i throughput T _Ri Saved by With the reference treatment capacity of step P _i as T _i , the unit number C _EPi of step P _i Saved by By the need to be treated per day in the production planning phase process P _i N _i, U _d in others responsible utilization, the process P _i of the required equipment number C _ENi C _ENi = N _i / (T _i ㆍ U _d / 100) Saved by, A product number missing in the subsequent step when the device E _j a O _fj in the stop _{S ij = {C ENi - (} C EPi R ij and _{T ij / T i)} T} i × O fj × U d / 100 To obtain by, and obtained according to the up to _{S i (S i = Max (} S ij, j = 1, 2 and and and n) of the above S _ij, In addition, the production management method characterized in that the number of empty pallets corresponding to the S _i is secured immediately before the step P _i . The method of claim 2, The number of the empty pallets is determined according to 100S _i / B _i with the yield of the process P _i as B _i . The method according to claim 2 or 3, The use ratio R _ji of the apparatus is determined so as to minimize the safety WIP number S _i within a range that satisfies the processing capacity T _Ri required in the process P _i . The method according to claim 2 or 3, The stop period O _fj is a production management method, characterized in that the longer of the planned offline time and off-planned offline time specified in SEMI E10-96 standard. The method according to claim 2 or 3, The stopping period O _fj is the reliability of the mean failure interval defined in SEMI E10-96 standard, k from the mean MTUO of off-plan off-time, the mean out-of-plan downtime interval MTUD, and the management period P days of production volume in the production plan. As the lower limit of, O _fj (day) = MTUOln (P / (kMTUD)} Production management method characterized by the above-mentioned. Process production line P _i the device group E _{j (j} = 1, 2 and and and n) is processed, and the processing step following P _{i + 1} the device group E _{k (k} = 1, 2 and and and m) As a production management method, When the safety WIP cannot be established between the process P _i and the process P _{i + 1} , the virtual process P _{i, i + 1} and the virtual device E _{j, k} are defined, and the virtual process P _{i, i + 1} is defined. Against safety WIP number, The use ratio of the virtual device E _j, the virtual process in _k P _i, the processing power of the _{i + 1} T _{j, k,} virtual device E _j, the virtual process P _{i, i + 1} of the _k R _{j, Let k} be the processing capacity T _{Ri, i + 1} of the virtual process P _{i , i + 1} . Saved by Let the reference processing capacity of the virtual process P _{i + 1 be} T _{i, i + 1} and the number of devices C _{EPi, i + 1} of the virtual process P _{i, i + 1} Saved by A production schedule wherein the virtual process, P _i, by a per day need be processed in the _{i + 1} to N _{i, i + 1,} U _d to the other responsible utilization rate, wherein the virtual process P _i, required equipment number of the _{i + 1} C _{ENi , i + 1} C _{ENi, i + 1} = N _{i, i + 1} / (T _{i, i + 1} ㆍ U _d / 100) Saved by A product number S _jO lacking in the next step when the device E _j a O _f in the stop Saved by If the device E _k has stopped O _f one day, the number of products insufficient in the next step S _Ok To obtain by, and obtained according to the maximum one of the above _jO S and _{S Ok S i, i + 1} (S i, i + 1 = Max (S jO, S Ok)), Further, immediately before the step P _i , a production management method characterized by securing an empty pallet of the number corresponding to S _{i, i + 1} . In a production line including a series of processes and processing a product by flowing a product in the series of processes, between the one step and the next step, the following A product that secures a safety WIP number S _i corresponding to the number of products that are lacking in the process, and which remains between the one process and the process before the one process with the stop of the apparatus of the one process. As a production management method to secure the number of empty pallets corresponding to the number of To the minimum number of safety WIP required to handle the processing number N _i necessary per day for each step i to the basic WIP number S _ki, can WIP plan of steps i S _Hi be the safety WIP S _i and the base Equation as sum of WIP number S _ki S _Hi = S _i + S _ki To obtain by, at that time, the safety WIP number S _i to the reference constant K _i is the planned value divides the WIP number S _Hi to the required processing can be N _i S _Hi / N _i, and set to be the same as the above-mentioned step i Production management method characterized in that. Process product P _i (i = 1, 2... M) is processed to the product by using device group E _j (j = 1, 2 ... n) by flowing the product through the process group. As a production management method of the production line which performs Device E _j can WIP of the process the product can be in process at S _Pj, device E _j store pallets waiting to be processed and the number of production processes can wait WIP in S _Wj, products and to terminate the processing of the device E _j atmospheric release of The number of products waiting to be returned to WIP number S _Fj and apparatus E _j to be carried out is set to the waiting number of WIP numbers S _Tj to be returned, and the use ratio of the apparatus E _j of process P _i is set to R _ij , and each process is required. With the operation rate U _i , the basic WIP number S _ki of the process P _i is By definition, In addition to the sum of the processes i to the WIP plan can S _Hi be the basic WIP S _ki and safety WIP number S _i S _Hi = S _ki + S _i To be defined as, The reference constant K _i of the step i defined by dividing the planned WIP number S _Hi by the number of treatments N _i per day required in the step i is set to ensure the desired value as the safety WIP number S _i . Production management method characterized in that. As a production management method of a production line which includes a series of processes and performs a required process for the product by flowing a product in the series of processes, Between the one process and the next process, the number of safety WIP corresponding to the number of products which are insufficient in the next process as a result of the device stop in the one process is secured, And securing a number of empty pallets corresponding to the number of products staying with the stop of the apparatus of the one process, between the one process and the process before the one process, Immediately after each step, empty pallets for WIP are prepared immediately after the same number as the number of safe WIPs. Immediately before each process, the same number of empty pallets with safe WIP numbers are prepared. And a step of maximizing the operation rate of the process when a failure occurs in the process, and transferring the immediately preceding WIP from the immediately empty WIP pallet to the immediately empty WIP pallet. The method of claim 10, And a step of transferring the WIP to the empty pallet for the immediately preceding WIP when the failure occurs in the step. As a production management method of a production line including a series of processes and processing a product by flowing a product in the series of processes, Between the one process and the next process, the number of safety WIP corresponding to the number of products which are insufficient in the next process as a result of the device stop in the one process is secured, Also, between the one step and the step before the one step, a number of empty pallets corresponding to the number of products staying with the stop of the apparatus of the one step is secured, The planned WIP number defined by the sum of the safety WIP number and the basic WIP number in each process is compared with the actual performance WIP number, and when the performance WIP number is less than the planned WIP number, the WIP is recalled from the upstream process. Production management method characterized by moving to a process. The method of claim 12, And the resultant WIP number is the sum of the WIP number immediately after the step and the immediately preceding WIP staying just before the step when the step is stopped. The method of claim 13, And when the device is stopped in the one step, changing the WIP immediately after the previous step of the one step to the WIP immediately before the one step. It includes the process group P _i (i = 1, 2 ... m), and flows a product to the said process group, and uses the apparatus group E _j (j = 1, 2 ... n) with respect to the said product. As a design method of the production line which performs the required processing, A process P _i to the following step between P _{i + 1,} as a result of the stop device of the process P _i to be safe WIP corresponding to the number of products that are insufficient in the step P _{i + 1} of To the processing capabilities of the apparatus for the process P _i E _j using the ratio of the T _ij, the process P _i of the device E _j to R _ij, the processing capabilities of the process P _i T _Ri Saved by, With the reference treatment capacity of step P _i as T _i , the unit number C _EPi of step P _i Saved by, By the need to be treated per day in the production planning phase process P _i N _i, U _d responsibility to others operating rate, the required number C _ENi device of the process P _i C _ENi = N _i / (T _i ㆍ U _d / 100) Saved by, A product number missing in the subsequent step when the device E _j a O _fj in the stop _{S ij = {C ENi - (} C EPi R ij and _{T ij / T i)} T} i × O fj × U d / 100 To obtain by, the method of designing a production line, characterized in that the securing according to the S _ij to the maximum of _{S i (S i = Max (} S ij, j = 1, 2 and and and n). _Production of the process P _i by the device group E _j (j = 1, 2... N), and the processing of the next step P _{i + 1} by the device group E _k (k = 1, 2 ... m). As a design method of the line, When the safety WIP cannot be established between the process P _i and the process P _{i + 1} , the virtual process P _{i, i + 1} and the virtual device E _{j, k} are defined, and the virtual process P _{i, i + 1} is defined. Safety against WIP The use ratio of the virtual device E _j, the virtual process in _k P _i, the processing power of the _{i + 1} T _{j, k,} virtual device E _j, the virtual process P _{i, i + 1} of the _k R _{j, Let k} be the processing capacity T _{Ri, i + 1} of the virtual process P _{i , i + 1} . Saved by, Let the reference processing capacity of the virtual process P _{i + 1 be} T _{i, i + 1} and the number of devices C _{EPi, i + 1} of the virtual process P _{i, i + 1} T _{i, i + 1} = Max (T _{j, k} ) Saved by, Scheduling onto the virtual process P _{i, i +} 1 day required to be treated in ₁ N _i, by a _{i + 1,} U _d to the other responsible utilization rate, wherein the virtual process P _i, necessary devices of the _{i + 1} number C _{ENi, i + 1} C _{ENi, i + 1} = N _{i, i + 1} / (T _{i, i + 1} ㆍ U _d / 100) Saved by, A product number S _jO lacking in the next step when the device E _j a O _f in the stop If the device E _k is stopped at O _f days, the number of products insufficient in the next step S _Ok The method of designing a production line characterized in that it is obtained according to the maximum of S _jO and S _Ok , _{i, i + 1} (S _{i, i + 1} = Max (S _jO , S _Ok )). . It includes the process group P _i (i = 1, 2 ... m), and flows a product to the said process group, and uses the apparatus group E _j (j = 1, 2 ... n) with respect to the said product. As a design method of the production line which performs processing, Device E _j treated article be the ends the processing of the processing of the WIP be the S _Pj, device E _j store the processing atmosphere can WIP air and process the number of products in the palette of S _Wj, device E _j out air in the in The number of products waiting to be transported is S _Fj , and the number of products waiting to be returned to the device E _{j is} the number of products waiting to be transported is S _Tj , and the use ratio of the device E _j of the process P _i is set to Rij, Assuming the required operation rate of the process U _i , the basic WIP number S _ki of the process P _i is By definition, In addition to the sum of the processes i to the WIP plan can S _Hi be the basic WIP S _ki and safety WIP number S _i S _Hi = S _ki + S _i To be defined as, Dividing the planned WIP number S _Hi by the number of treatments N _i per day required in the step i, and setting the standard schedule K _i of the step i defined as the safety WIP number S _i to ensure a desired value. The design method of the production line characterized by. It includes the process group P _i (i = 1, 2 ... m), and flows a product to the said process group, and uses the apparatus group E _j (j = 1, 2 ... n) with respect to the said product. As a production line that performs the necessary processing, Having one of the process P _i to the same empty pallets between the next process P _{i + 1} of, as a result of the device is stopped in the step P _i and a number of safety WIP corresponding to the number of products that are insufficient in the step P _{i + 1} and, Immediately before the one step P _i, an empty pallet equal to the safety WIP number is provided, The safety WIP number is The processing capabilities of the process P _i of the device E _j T _ij, by the use of the ratio for process P _i of the device E _j to R _ij, process P _i throughput T _Ri Saved by, With the reference treatment capacity of step P _i as T _i , the unit number C _EPi of step P _i is Saved by, By the need to be treated per day in the production planning phase process P _i N _i, U _d responsibility to others operating rate, the required number C _ENi device of the process P _i C _ENi = N _i / (T _i ㆍ U _d / 100) Saved by, A product number missing in the subsequent step when the device E _j a O _fj in the stop _{S ij = {C ENi - (} C EPi R ij and _{T ij / T i)} T} i × O fj × U d / 100 The production line characterized in that it is set so that the largest thing S _i (S _i = Max (S _ij , j = 1, 2 ... n)) of said S _ij may be obtained. Process the device group to _{P i E j (j = 1} , 2 and and and n) is processed, and then the process P _{i + 1} the device group E _{k (k} = 1, 2 and and and m) is processed, and At this time, as a production line that can not establish a safety WIP between the process P _i and the process P _{i +1} , Between the process P _{i + 1} and the next process P _{i + 2} a, as a result of the device suspended in the process P _i to the same empty pallets to the number of the safety WIP corresponding to the number of products that are insufficient in the step P _{i + 1} Equipped, Immediately before the one step P _i, an empty pallet equal to the safety WIP number is provided, The safety WIP number is Virtual process P _{i, i + 1} and virtual device E _{j, k} are defined, and for the virtual process P _{i, i + 1} , The use ratio of the virtual device E _j, the virtual process in _k P _i, the processing power of the _{i + 1} T _{j, k,} virtual device E _j, the virtual process P _{i, i + 1} of the _k R _{j, Let k} be the processing capacity T _{Ri, i + 1} of the virtual process P _{i , i + 1} . Saved by, Let the reference processing capacity of the virtual process P _{i + 1 be} T _{i, i + 1} and the number of devices C _{EPi, i + 1} of the virtual process P _{i, i + 1} Saved by, A production schedule wherein the virtual process, P _i, by a per day need be processed in the _{i + 1} to N _{i, i + 1,} U _d to the other responsible utilization rate, wherein the virtual process P _i, required equipment number of the _{i + 1} C _{ENi , i + 1} C _{ENi, i + 1} = N _{i, i + 1} / (T _{i, i + 1} ㆍ U _d / 100) Saved by, A product number S _jO lacking in the next step when the device E _j a O _f in the stop Saved by, If the device E _k has stopped O _f one day, the number of products insufficient in the next step S _{Ok Obtained} according to, the production line characterized in that determined according to the maximum of S _jO and S _Ok S _{i, i + 1} (S _{i, i + 1} = Max (S _jO , S _Ok )). In a production line with a plurality of bays, Each bay has a stocker, Wherein the number of pallets of the stockers of each bay is determined so as to accommodate at least the total number of safety WIPs of the previous processes belonging to the bays. The method of claim 2, Instead of the process group P _i (i = 1, 2... M), if a restriction by the type of the product to be processed in the process P _i is imposed on the use of the device E _j in each process P _i . The process variety group Pi (i = 1, 2 ... z) which divided | divided the said process group by the kind of a product is defined, and for each of the process varieties contained in the said process variety group P _i , the said safety WIP and A production control method comprising the step of calculating a basic WIP.