Size factor in sample drawing procedure

[former_member220469]

Dear all,

                          I have few doubts in the below fields in "Sample Drawing Procedure" in QPV2.

1. Size factor:

                        When I enter the value for this field as 1,  all primary, pooled and reserve samples are getting generated

Example, GR qty of the material is 50 Ea

                Sample size in sample scheme is 30 Ea

                No of Primary samples in SDP is 5 samples

                No of Pooled samples in SDP is  1 Sample

                No of reserve sample is 1 sample

When the "Size factor' in SDP is 1, system generated the sample size of 31 Ea (30 Ea of pooled sample and 1 Ea of reserve samples)

But, when I increase the "Size factor of primary sample" in SDP as 2 Ea, system is only generating Primary samples and it is not generating Pooled and Reserve samples.

Example, GR qty is 50 Ea

                sample size in sample scheme is 30 Ea

                 Primary sample is getting generated for only 30 Ea

                 No Pooled and reserve samples are getting generated

I read the Help manual for the definition, I am unable to understand clear purpose of this "Size factor" in Primary and Pooled samples and when should be used

Am I proceeding in correct direction??????????

2. What is the purpose of "Sample quantity" field in "Reserve sample" ?????

I have searched enough threads and help manual, I am unable to understand the purpose and usage for these threads

Please throw some light on this issue

J.Balakrishnan

[Former Member]

1.Yes,this beheviuor is very much as FF has suggested.

Problem here is not only the size factor.Most influencing factor in this case is "Inspection lot size "

Consider a practical example wherein ,you have IL qty 50 EA and out of which you have to draw samples in a lab as per SDP.when size factor is 1 you can not have 5 primary samples with 30 EA( Had lot size been 50 KG ,the you can draw 5 primary samples with 30 gms ) Hence system in first case calculated pooled.

When size factor increased ,system now can not draw eaven pooled samples 2*30 EA =60EA as lot size is less than total sample calcualtion.This is due to Lot size.

So be genorous & increase lot size or reduce sample size in sampling scheme.

2.Sample quantity : In Short is it not different from other sample quantities.In reserve it represent the total qty of reserve samples that you will draw from pooled or primary

[former_member220469]

Dear FF/Sujit sir,

                                    Thanks for your valuable answer. My doubt regarding the "Size factor" has been cleared and SDP is working fine.

My final doubt in sample drawing procedure is

   What are the functions of the below fields

1. Highest Partial Sample No. Valid for Instruction in QPV2

2. Partial Sample No. for Inspection Charac. in Task List

I am unable to understand the concept of these fields. Please help me to understand the usage and functions of these fields

J.Balakrishnan

[former_member42743]

Partial sample numbers can be used to link together MIC's that can be tested using the same sample.  For instance one sample might go to a wet chemistry label where ph, viscosity and total solids are tested.  These MIC's would be assigned partial sample #1. 

You then have a dozen MIC's to record the values from the peaks of a GC run.  You assign the 12 MIC's to partial sample #2.

Thus you have one sample going to the wet chem lab, and another sample going to the GC lab.  This work can than be done in parallel by two different technicians.

For highest Partial Sample No. Valid  - under a sample drawing procedure you can set up multiple sample-drawing items. 

In the example I made above with the Wet Chem and GC lab, I could chose to create one sample-drawing item or two.  If I set up one, with a highest partial sample number of 2, then whatever is defined is used to calculate the sizes of both sets of samples.

If I choose to set up two, sample-drawing items, one would have a highest sample number of 1 and the other 2.  Then I could have different amounts calculated for each sample set.  I.e. I might need 4x the amount of sample for the Wet Chem area as I do the GC the lab.

If I had 4 partial samples set up in my inspection plan.  I could have 1, 2, 3 or 4 sample-drawing items.

For instance, the first sample-drawing could have a highest partial sample of 3, and the second one 4.  In that case the first sample-drawing item calculations apply to sample sets 1, 2 and 3.  The second sample-drawing set only applies to 4.

Hopefully this helps.

FF

[Former Member]

In addition to what FF said,In short partial sample number helps you to select different sample drawing item for different operations.

[former_member42743]

In your example 1)

You received in a Qty of 50.

Yet you've designed your sample size to be 30.  Now because you requested a size factor of 2, that sample size is doubled, to 60.  But you don't have 60 in your received qty.  So how can it double it? 

I don't know if that is why your pooled and reserved samples are not being calculated, but I could see how it might cause that problem.  Your pooled sample is expecting to pool together 60 EA which you don't have available in the received quantity. If the system thinks the entire qty is consumed by the GR samples, than there is none available for reserve sample.

Typically, I wouldn't use a size factor if my UOM is an "Each" or a "Piece".  The size factors are usually used more often when you are dealing with liquids and powders where you might be drawing off ounces, or grams of material for testing.  It is really intended to allow you to have a buffer of material available in the event a sample is dropped on the floor, a vial breaks, a machine standards fail and a retest needs to be performed, etc, etc...  If you are doing AQL sampling where your UOM is an each, you normally aren't going to double (i.e. Size factor of 2,), the amount specified by AQL.  If you want some extra samples pulled, I'll usually do this by specifying 1 or 2 extra units in the reserve sample.

In your second question:  It is the quantity of material you want for your reserve sample.  Reserve samples are typically a fixed quantity and not based on lot sizes.  Most places for example usually will take a fixed sample of 1 each.  So if your fixed number is 1 and your sample quantity is 1, than obviously you are pulling one from the received quantity.  If your fixed quantity is 1 and your sample quantity is 2, you're pulling one sample of 2 EA. (i.e. both would use the same physical sample number). 

If you specify a fixed sample of 2, and a sample quantity of 1, you are still pulling 2 EA, but in this case each sample would get their own physical sample number assigned.

If you specify a fixed sample of 2, and a sample quantity of 2, you are pulling 4 EA.  You'll have 2 sample numbers, with 2 labels for each sample number.

I hope this helps.

FF