Gas Compliance/Maintenance Process Improvement Utilizing GIS
The first step was to summarize the number of valves by gridsheet and overlay this on the roads, pipes, valves and gridsheets. This allowed the local supervisor to look at both the number of valves and their relative location on the landbase. At this time there was little concern with the actual month the valves were currently being maintained. It was decided that all valves should be completed during the first ten months of the year. Our “pilot” division had 3,286 valves. Therefore, maintaining roughly the same number each month would yield an average workload of 320 valves per month. It was estimated that the new system should allow a worker to turn a minimum of 30 valves a day and only require the first two weeks each month to complete the work. This would leave the last two weeks to take care of any problems that were found during the maintenance. Ten new zones were created using the valve plots. Now a new month had to be assigned
to each zone. An analysis was performed to determine the predominant maintenance month for each of the new zones. It was known from the start that this would be a two-year process to get all of the zones synched up. The latest allowable maintenance date (annually, not to exceed 14months*) was calculated for each valve in a zone and compared to the assigned month for that zone. Some valves had to be turned later the first year so they would fall within the correct month the following year. Some valves needed to be turned twice the first year to stay within compliance.
Once the valves had been assigned to a new month based on geographic area, a suggested route for maintaining the valves was created. It was discovered during our field work that the technicians visited the valves in the exact order they were printed out on the maintenance sheet. Using the routing algorithms in GIS, the shortest path required to visit all the valves in each zone was determined. The new database was given an order
variable and the new printouts were sorted and printed with the new suggested order. The local technician was given the opportunity to suggest a new route as field conditions dictated.
After refining the process in pilot area it was implemented in all areas except one. One area’s office decided it was too late in the year to make anymore changes and asked if they could be allowed to delay their implementation until the next year.
The benefits of the new system were seen in the first month. The field technicians turned a record number of valves in the first two weeks. Originally, it was thought that each person in the field could complete 25-30 valves per day, but they were completing 50+ on a good day. This freed up a significant number of man-hours for other maintenance work.
|
