The first club session of the year was held by Opera on 24-Jan-2011. The session introduced SPC - “Statistical Process Control” Tool to the SOM students. It was a knowledge sharing session in which the concept and the application of the tool were discussed along with training on Excel for conducting Cp, Cpk Study. Swethadri B, SOM12 student presented the concept and the excel tool to conduct the study followed by application of SPC by Meghna Tyagi, SOM11 student. In his presentation Swethadri shared his experience in Bosch Limited and Wipro e Peripherals related to the application of the tool. Meghna presented her summer internship project “Process Capability Roll-out in Mulund Plant of Johnson and Johnson” to explain the application of the SPC tool.
Statistical Process Control or SPC is a tool which helps in identifying the variation in the output from the desired level. Ideally, the variation should be within the tolerance limit from the desired level. But that seldom happens in a manufacturing industry resulting in losses. This tool assists in –
· Improving product Quality.
· Increasing product consistency.
· Decreases scrap and rework of products.
· Increases production output.
The variation in the data can be measured easily by collecting sample data of 100-125 nos (as per industry standards) in a periodic sequence. This data is then fed into the excel tool which calculates the variation in the data w.r.t desired value. Two indices which are of particular importance are Cp and CpK.
Cp is the Process Capability which tells you how capable the process is to give consistent output. It is a measure of the p. Higher the value of Cp, the more capable your process is. As per industry standard, the Cp value should be above 1.33.
CpK is the Process Capability Index which tells you how accurate the process is in giving the output. Again, higher the value of CpK, the better is the process. As per industry standard, the CpK value should be above 1.67.
Cp gives the measurement of process distribution while CpK gives the process cantering.
Summer Experience Sharing-
It was interesting to see how the concept of SPC could be used during our summer projects. The summer project of Meghna in J&J was entirely based on SPC and it was used to determine the process capability of the manufacturing lines for Bandaids, Sanpro and Baby Powder. In case of baby powder, this tool was used to identify the following parameters –
1) Variation in weights of the powder bottles.
2) Quantity of perfume used, labelling, cap fitment and sleeve.
Data for finished weights of the bottle was collected from the manufacturing line on an hourly basis for the entire day. The variation in the weight was studied and based on the Cp, Cpk values a fishbone analysis was conducted to identify the probable reason for the variation.
By understanding the application of Statistical process control tool in this summer project, we realised that though this tool is very easy to use, it can be highly effective in indentifying the variation in your manufacturing processes. The statistical process control tool is very easy to use.
In the end Madhavan Pillai, Opera11 Club Co-ordinator emphasised on the importance of the club activities and also shared his summer internship experience providing valuable tips to the first year students.
Opera plans to keep many more sessions in future to provide inputs on relevant industry tools and topics like Value Stream Mapping, Value Stream Designing, Six Sigma, PPAP(Production Part Approval Process), Lean Manufacturing, TRIZ(Theory of inventive problem Solving) and others.
Puneet Shah (For Opera Club),
SJMSOM Class of 2012.