Scheduling of Batches in Discrete Mfg

[Former Member]

Hi all Experts,

I am having problem in scheduling of Batches in Discrete Mfg. Plant capacity is 200MT/month. Process includes 9 operation. Each operation are having different nos of Work centers. Batch size for each operation is 1900kg. It is Make to stock process. When I do scheduling through Routing for Month Quantity say 200MT, Last Operation starts after six month. In house Prod Time for 1 Batch to finish is 5.6 Days. Every 4 Batches should come. But in scheduling whole quantiy 200MT is processed first then it goes to 2nd Operation. So this takes more than six months to start last operation. I tried combining Splitting and Overlapping with go ahead qty 1900 (Batch Quantity). Time has reduced to 40 days to start last operation. But I want to start the last operation after 5.6 Days only irspective the total quantity given for scheduling. How to solve this Problem? Please u can send me answers to mil_ind2001@yahoo.co.in

Thanks,

Milind Rahangdale

[Former Member]

you need to have a Fixed lot size with qty 1900. Then system will create 2 Planned orders and your scheduling will be perfect.

[Former Member]

Hi Mr Pradeep and Rajesha, I will explain to all of you again in following way.

Plant capacity is 3 Batches of 1900kg/Day. Discrete Manufacturing.

Reaction Operation-1 with 8 Capacities, BCT=40hrs. All different batches will run in all capacities.

Distillation : Operation-2 with 2 equal capacities BCT= 10 Hrs

Hydrolysis Operation-3 with

3 equal capacities. BCT=12Hrs

Like this after Hydrolysis,

Filtration Operation with 2 equal capacities(BCT=8Hrs),

Pressure Reaction with 3 equal capacities(BCT=20Hrs),

Reaction with 3 capacities(BCT=20Hrs),

Washing with 2 capacities(BCT=8 Hrs),

Distilation-1 with 1 capacity(BCT=8 hrs) and final Operation

Distillation-2 with 1 capacity (BCT=8hr).

In above operation here will be only batch to batch operation. No mixing of 2 batches.

From this final operation Product comes out with 1900kg output. Every day 3 Batches of each 1900 kg should come out.This final stage decides the plant capacity. Once we start 1st operation, after5.6 days 1st batch will come out and then continuously one batch after another.

I think this might have given sufficient explanation to all of you. Now I need to do scheduling in such a way that everyday I should get 3 batches/day. How to do this? Please give ur important inputs right from routing to MRP and Production order creation. Thanks,

Milind rahangdale

09966449749

[Former Member]

what is BCT?

what do you mean by -

Operation-1 with 8 Capacities, BCT=40hrs. All different batches will run in all capacities

Is it mean that we can have 8 batches running paralally in operation 1?

How nuch time it will take to come out of opration 1?

Example -

I hope batch size is 1900 kg, hence in opration 1 we can have 8 batches of 1900 kg which will take equal time to finish as we have 8 capacities. Hence if your quantity is 1900X8 = 15200 TO, then if i assume the time required in operation 1 to finish 8 batches is 1 day. then all 8 batches will be ready after 1 day. Is it right?

[Former Member]

pl come back

[Former Member]

Yes Mr Rajesh,

I could do this scheduling succefully. BCY Means Batch Cycle time for completion of one Batch in one capacity. This means all 8 batches will run paralally in operation-1. 40 Hrs will take to come out of operation-1. This is BCT. like this all operation have diferent BCTs. Batch size is 1900kg. The Batch will come first from operation-1 should proceed to next operation2 and so on till end.In my last explanation I explained that from last operation-9(distillation2) max 3 batches will come every day. But any I could do it successfully by combination of splitting operation into their capacities and In overlaping of operation taking continuous Prod. with go ahead qty 1900kg, minimum processing time= BCT of same operation and overalping tme= BCT of same operation. Now I can Plan for any qty and I get last operation start date after around 5.6 whatever comes from totaling of all Operation BCTs.

Thnks for interaction.

Milind

[Former Member]

Hi Milind,

What i understood is to finish one batch, ie to complete 9 operations, u need 5.6 days. Then how the last operation of one batch will start after 5.6 days.

Since the each operation is being done in seperate workcenter u can do the capacity leveling by despatching the operation after creating the production order.

Please try and come back

Regards

Pradeep