Plant Shutdown - Resource Allocation

Hi All:

I am involved in a shutdown project and where have encountered the case detailed below

  1. The Activity Duration is 132Hrs (12Hrs x 11 shifts) & each shift is different with different mix of resource requirements.
  2. Please note that I have delinked the option to calculate activity duration basing on resource assignments (Edit-User preferences-Calculations)
  3. After the resources are assigned as below as per the respective calendars, I find that the resource budgeted/planned hours are not being allocated shift wise rather it is distributed to the entire duration of the Activity from start to finish.
  4. Kindly advise how to solve this case.

 

 

Time scale (Day/Shift)

Start

5/05/2011

6/05/2011

7/05/2011

Project Calender: 2 Shifts – Day (6am-6pm) & Night (6pm-6am)

Day 5

Night 5

Day 6

Night 6

Day 7

Night 7

Activity 1 – Resources Required

F22+F23+R6+R7

  F22+F23+TR3+BM7

F22+F23+R6+R7

TR2+BM1

TR2+BM1

 

Resource Hours Budgeted

48hrs (4x12Hrs)

0

48hrs (4x12Hrs)

24hrs (2x12Hrs)

24hrs (2x12Hrs)

0

 

 

 

 

 

 

 

 

 

 

 

 

 

Time scale (Day/Shift)

8/05/2011

9/05/2011

Finish

10/05/2011

Project Calender: 2 Shifts – Day (6am-6pm) & Night (6pm-6am)

Day 8

Night 8

Day 9

Day 8

Night 8

Day 9

Activity 1 – Resources Required

NDT

C1+R6

 

NDT

C1+R6

 

Resource Hours Budgeted

12hrs (1x12Hrs)

24hrs (2x12Hrs)

0

12hrs (1x12Hrs)

24hrs (2x12Hrs)

0

 

 

 

 

 

 

 

 

 

 

 

Resources Legend: F - Fitter, R - Rigger TR - Trade Person, BM - Boiler Maker,  NDT - Non-destructive Testing Team, C – Crane

Resources Calender: 1) Day Shift (6am – 6pm) 2) Night Shift (6pm – 6am)

S
Srinivas Gajjarapu 👤 Member for 17 years 3 months

Hi Rafael,

Thank you for the suggestions. I got your point. I will split up the parent activity in to sub-activities and assign the resource mix to each of the respective sub-activities.

I have a doubt again,

For/while doing the above said, I have created a seperate WBS for such parent activity and made the parent activity in to a "WBS Summary activity". Now, should I assign the total list of resources (including relationships and calender) needed to complete the parent activity to this so called WBS Summary activity?

Basically I need need to understand the logic behind using the WBS summary activity viz. its features and functions.

Please advise.

Regards,

Srinivas

R
Rafael Davila 👤 Member for 22 years 3 months

Avoid Bucket Planning, is wrong, is misleading, is dangerous as it overrides CPM logic. It is the lazy scheduler solution when you shall be able to assign resources without overriding CPM resource assignment logic.

Your request for resource assignment is simple as shown in the following diagram, I am assuming work by all resources to be independent of each other as I don't have information on which are to be scheduled as meeting, in such case keeping them together in teams will do it at a few clicks of the mouse.

Plant Shutdown r1

R
Rafael Davila 👤 Member for 22 years 3 months

For shut down project where you have to model shift work P6 might not be good at all.

Beware that some software cannot correctly model shift work when the duration of the activity is driven by how much work is produced by the resources on different shifts. I understand neither MS Project nor P6 can deal with this issue unless new versions were updated to correctly model shift work.
You can try yourself a simple scenario.
 

Activity 1
500cm rock excavation
Resource 1 production 10cm/hr  and works Monday, Tuesday and Wednesday 10hrs/day
Resource 2 production 15cm/hour and works on Wednesday, Thursday and Friday 10 hrs/day
If activity starts on Monday:
Monday =>> Resource 1 will produce 100 cm
Tuesday =>> Resource 1 will produce 100 cm
Wednesday =>> Resource 1 will produce 100 cm
Wednesday =>> Resource 2 will produce 150 cm
Thursday =>> Resource 2 will produce 50 cm in about 3 hours
Activity will take 3 days 3 hours.
If activity starts on Wednesday :
Wednesday =>> Resource 1 will produce 100 cm
Wednesday =>> Resource 2 will produce 150 cm
Thursday =>> Resource 2 will produce 150 cm
Friday =>> Resource 2 will produce 100 cm in about 7 hours
Activity will take 2 days 7 hours.
 

If your software is not capable of modeling the above, simple shift work on a single activity, then you are using the wrong tool. Every time the activity is delayed, the distribution of work is shifted, when you have many such activities and work on different hour shifts, different days it can become quite complicated. Distributing work by hand is nuts.

I suspect you will be in need of a work around like dividing the activity into separate activities, one for each shift, then manually adjust work distribution. Still it will be wrong modeling, it is simply a single activity worked on multiple shifts, nothing more, no big deal.

Another option might be to forget all you learned about CPM and bypass all rules using Bucket Planning, an even worst than bad alternative. What will happen if your activity is delayed, will the model make the necessary adjustments in resource assignments? I believe this is what you are doing as the calendars do not match assigments, just take a look at R6 is assigned a day shift on days 5 and 6 and a night shift on day 8.

You have de-linked the option to calculate activity duration basing on resource assignments (Edit-User preferences-Calculations) this shall make it a simple condition to model. Maybe your job is too big, a single activity is too much for your software !!!

It is hard to follow your example as it can be you do not have a single activity issue but several activities in tandem and in such case you shall have no problem at all.
 

Regards,
Rafael
 

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