Mm-Safety Stock

Safety Stock is just a general statement. This article summarizes the four Security Stock (time) settings of SAP to increase the flexibility of the inventory quantity (time) during the planning process. Why does the security stock increase the elasticity of the plan? In net requirements calculation, quantity available = Fixed receipts + stock available for planning-safety stock-requirements reports missing materials if the available quantity is less than zero, batch age quantity or demand quantity (net requriements) will be used for batchcompute and final suggestions.

• Safety Stock
• Safety Stock partially available
• Dynamic Safety Stock
• Safety time

I. Safety Stock

This is the "safety stock", and the quantity of safety stock is not available in the plan. In MRP, if the quantity of materials is lower than the safety stock level, a planned order is generated. Safety Stock is set in the mrp2 view of material master data.

Ii. Safety Stock partially available

If a safety stock is set, a replenishment request is generated at a lower level, even if it is missing, which increases the planned workload. To make up for this deficiency, we can set a percentage in the MRP group. Only when the safety stock falls below this percentage will the replenishment requestor generate.

Iii. Dynamic Safety Stock

Dynamic Security inventory is even more powerful. It determines the security inventory level in the next few periods based on the average daily demand (average daily requirements) (the quantity is equal to several average daily requirements ): minimum inventory, target inventory, and maximum inventory. If it is smaller than the minimum inventory, a replenishment request is generated to the target inventory. If it is greater than the maximum inventory, the system will prompt the exception information. If the security stock is set at the same time, it will be accumulated. This configuration is called range of coverage profile, which is allocated in the mrp2 view and configured in IMG: Production-MRP-planning-MRP calculation-define range of coverage profile (dynamic safety stock ).

Iv. Safety time

The first three solutions are security stock quantity settings, and safety time is the margin of time settings. The proposed replenishment time of materials will be prior to the actual demand time, and the advance date will be configured in the mrp2 view. Considering that materials may be used at different levels of the product, in order to avoid repeated advances, you can set the Security Time in the safety time indicator column of mrp2 view to be effective for all requirements or only relevant requirements, or simply not. Considering the different security time length requirements for different periods, you can define the period profile in the background, IMG: production-MRP-planning-MRP calculation-define period profile for safety time/actual range of coverage and assign it to the material in mrp2 view.

Note: The percentage is set based on the flat group, in the background: define safety stock availability.

Dynamic Safety Stock:

The dynamic safety stock is calculated in the planning run of the order proposal quantity. in the MRP evaluation, md04-you can check the parameters used to calculate the dynamic safety stock in the period totals display. to set the dynamic safety stock themaster data settingsrequired are,

1. Maintain MRP view.

2. In MRP 2 view enter the coverage profile which in configuration will carry the elements required as detailed below.

3. material master-you have MRP type PD. It is maintained in spro under the node->

Spro-production-Material Requirements Planning à planning-MRP calculation à define range of coverage profile (dynamic safety stock ).

It is maintained with respect to a plant as the calculation is plant specific. calculation-
Thedynamic safety stockis calculated using the following formula: average daily requirements * range of coverage

The individual parameters are described below:

Average daily requirements
The calculation of the average daily requirements is carried out using the following formula: requirements in the specified periods/number of days in the total period lengthyou must maintain the following parameters for the calculation of the average daily requirements:

1. Period indicator
You use this indicator to determine the calendar period for which you want to carry out the average daily requirements.
Here you can enter the following:

• Weeks (W)
• Months (m)
• Periods according to the planned calendar (k)

2. Type of period length-you use this indicator to determine the length of the individual periods in detail.
Here you can enter the following:

• Workdays
• Calendar days
• Standard days-if you select standard days as a period length, you must determine the number of days per period in the field, "No. Standard days"
  If you set standard days as the period length, you must enter the number of days per period in the "No. Standard days" field.

3. Number of periods
Here, you define the number of periods you use to calculate the average daily requirements.

Determining the range of coverage

You can determine the range of coverage for a maximum of three periods and you can maintain different coverage for each period.
To do this, you must define the ranges of coverage and the periods in the screen section entitled, "determine range of coverage ".
You also have the option of limiting the range of coverage in each of the three periods by entering a minimum and a maximum range of coverage. the system checks whether the actual range of coverage (available quantity/average daily requirements) lies below the minimum range of coverage or above the maximum range of coverage. if this is the case, the dynamic safety stock level is recalculated using the information for the target range of coverage.

Example-1
Coverage profile-001, with following settings assign in material master-mrp2 view, Period type = m
No of period = 2
Type of length = 3 and days/period = 20.

Range of coverage for first period (target) = 3, no of periods = 2
Lets us say requirements areas below-
12.11.2007 to 1000
19.11.2007-2000no of days = 2*20 = 40
Average daily requirement = (1000 + 2000)/40 = 3000/40 = 750

Safety Stock requirement = 750*3 (target) = 225.run MRP, result is as below
12.11.2007-pl order qty-1225 available qty-1225
12.11.2007-VSF 1000-available qty-225
19.11.2007-pl order qty-2000 balance-2225
19.11.2007-VSF 2000-available qty-225.

Example-2

Coverage profile-002, withfollowing settings, assign in material master-mrp2 View
Period = m
No of period = 1
Type period = 1 I. e. working days as per factory calendar, please check your factory calendar. it is taking form no of days of factory calendar, remove the days which already passed, then remove holidays.
Example-in factory calendar-
 
2, 3, 9, 10, 16, 17, 30 are holiday. I, E 9 days in 30 days are holidays,
First, today is Le us say 8th, hence from 30 days remove 7 days, (as it is already passed), hence left with 23 days.
Holidays applicable are, 9, 10, 16, 17, 23,24, 30 I. e. 7 days I. e. From 23 days I need to remove 7 days hence the working days are only 16 days.
Range of coverage = Target 7, no of period = 1.
Now my requirement is 3000 in that month
Daily average consumption is 3000/16 = 187.5
Safety Stock = 187.5*7 = 1313.
 
12.11.2007-pl order-1 qty 2313 available qty-2313
12.11.2007-VSF 1000-available qty-1313
19.11.2007-pl order-2000 available qty-3313
19.11.2007-VSF 2000-available qty-1313.

I hope the above 2 Examples clears the concept of dynamic safety stock calculation.

Original article:

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