SIPOC Process Map
The acronym SIPOC stands for supplier, input, process, output and customer and is used primarily as a high-level process map. SIPOC maps are particularly useful in the define stages of a Six Sigma project for two reasons. First, the structure of the map emphasizes the importance of causal relationships in any business activity (inputs go into a process and create outputs). Second, the SIPOC methodology identifies all players in a process and their role in delivering a product or service.Preparation of the SIPOC map actually begins with the process itself. Because it is a high-level map, steps in a given process are normally limited to half a dozen key activities. As each process step is identified, team members work backward to determine what the initial input is into that step, as well as who the supplier of the input is. Then moving forward, the output of the process is identified, as well as who the customer of that output is. Requirements associated with each process step are listed on the far right.Table 9.1 displays an SIPOC process map that was developed from the preceding five why analysis. The Buchanan team decided to focus on inbound materials flows due to the fact that the answers provided pointed to upstream problems (supplier inputs) that were causing faulty outputs (timely deliveries). The team hypothesized that while growing inventories were symptomatic of a problem, the real illness may be associated with the management of inbound flows of raw materials from China to the plant in Columbus, Ohio.Supplier | Inputs | Process | Outputs | Customer | Requirements |
---|---|---|---|---|---|
Buchanan Automotive | Materials requirements plan | Purchase order released | Raw materials order | Columbus, Ohio plant | |
Supplier's logistics department | Pickup request | Asia supplier contacts origin 3PL firm for pickup | Documents and cargo picked up | Columbus, Ohio plant | Documents and cargo ready for export |
3PL firm at origin | Cargo is labeled, consolidated and sent to airline | Origin 3PL exports goods | Export shipment | Columbus, Ohio plant | Airway bill, invoice and packing list matched via 3 Cs methodology |
3PL firm at destination | Airway bill, invoice, packing list and customs entry | Cargo arrives and clears customs | Entry presented to customs | Columbus, Ohio plant | Classification and valuation of goods |
Local trucker | Customs release and delivery order | Local delivery | Delivery to plant | Columbus, Ohio plant | Customs release document (delivery order) |
Normally, SIPOC maps are used in the define stage of a project to help team members visualize inputs and outputs of a process on a high level. As projects move into the measure and analyze stages, more detailed process maps are utilized to quantify the existing state of a process. In some cases, however, SIPOC maps reveal enough about a process to shine a spotlight on suspected root causes via a detailed process map.After preparing the SIPOC map of inbound materials flow, a specific activity in the process stuck out in the minds of the team members. Isolated in Table 9.2, step two in the SIPOC process required the supplier at origin to contact a third-party logistics (3PL) provider for a local pickup. The output of the process was the collection of both cargo and commercial documents by the 3PL firm. If the five why analysis revealed that documents were either missing or contained errors when they arrived at U.S. Customs, the team wanted to know the precise nature of the interaction between the supplier and 3PL firm at origin. It was for this reason that the team decided to take an early look at the inbound process via a more detailed process map.
Supplier | Inputs | Process | Outputs | Customer | Requirements |
---|---|---|---|---|---|
Supplier's logistics department | Pickup request | Asia supplier contacts origin 3PL firm for pickup | Documents and cargo picked up | Columbus, Ohio plant | Documents and cargo ready for export |