Preventive maintenance schedule - HxGN EAM - Version 11.07.01 - Feature Briefs - Hexagon

Downtime due to planned or preventive maintenance activities has an impact on the Production Planners in the same way unplanned work does. Therefore, Maintenance Administrators must identify any resources that will be impacted by equipment PM schedules and the maintenance activities performed.

The Maintenance Planner creates a PM schedule as a template for recurring work orders on assets. The PM Schedule screen is used to create and edit PM schedules identifying planned work that must be done and on what frequency the work is to take place. The screen below shows PM schedules created for a drill station and cutting station that are to be performed once a month on a production line.

For Advanced Maintenance Planning purposes, a production details section has been added to the existing PM Schedule screen. Production priority requested start date, and request end date must be present on the resulting work order before a production request can be generated as these are important criteria used by Production Planners to evaluate production requests. Therefore, production priority, requested start date buffer (days), and requested end date buffer (days) have been added to the PM Schedule screen. As work orders are generated from PM schedules the values in these fields will be used to populate production priority, requested start date, and request end date for each work order.

Once a PM schedule header is created, the equipment for PM schedule screen is used to associate all equipment for which the PM applies. Maintenance Administrators have the option to vary the PM frequency and due date for each PM equipment.

The resources for PM schedule screen are used by the Maintenance Administrator to associate resources that are impacted when work is performed on the selected PM schedule and equipment. In Resources for equipment equipment SX135321 (cutting station – line 1) is associated to resources L1J (line 1 – drill station) and L1R (line 1 - cutting station. Because of this relationship the system automatically associates the appropriate resources with the PM schedule as equipment is added to the PM schedule (see the following image). Cool-down and warm-up times for each resource will default from the equipment record and can be changed on the PM, as necessary. The Maintenance Administrator will then need to enter the amount of actual downtime (not to include cool-down and warm-up times) each resource is expected to experience when the PM activities are performed on the equipment.

This step in the setup process is important and is one in which the Maintenance Administrator may need to give significant thought. If the resources associated to the PM equipment will not be impacted at the same time, then the resources should be sequenced in the order in which they will be impacted.

The system automatically generates PM work orders for all equipment associated to the PM schedule. The image below shows cutting station SX135321 has a monthly preventive maintenance task due on 9-13-2008. Details of the maintenance and the work order itself are contained on the Activities and Work Order pages for the PM Schedule.

As PM work orders are created for equipment for which the Track Resources check box is selected, the system will:

• Copy the production priority on the PM schedule to the work order header.

• Calculate and populate work order req. start date:
  Sched. Start Date – Req. Start Date Buffer (Days)

• Calculate and populate work order req. end date:
  Sched. End Date + Req. End Date Buffer (Days)

This ensures that production requests can be successfully created for PM work orders without the need to enter this data onto each work order manually. This buffer window on the schedule start and end dates for the work order provides flexibility for Production Planners to schedule resource availability.

Let us examine the two resource records associated to PM schedule CS-MO-001 and equipment SX135321 to better understand how these records describe this PM’s impact on the ERP:

In this example, resource L1J will be impacted first (via Sequence value) for a total of 160 hours (100 + 30 + 30) and will then be available once again for ERP resource scheduling. Because the offset value for sequence 2 is 0, resource L1R will be impacted as soon as L1J is back online. Resource L1R will also be unavailable to resource planning within the ERP for 160 hours. See the figure below.

What if PM schedule CS-MO-001 on equipment SX135321 requires both resources simultaneously? How would the PM resource records need to be setup in this case?

All data would be the same except an offset value of 160 hours is required. If the sequence 2 resource is impacted beginning with the completion of impact on sequence 1 resource (offset value = 0), then offsetting sequence 2 by 160 hours effectively causes them to start at the same time. One could define offset value as the amount of time for which the resource, where the offset is defined, overlaps the previous sequence’s resource. See the below the following table.

As the Maintenance Administrator inserts, updates, or deletes resources associated to the PM schedule the system automatically logs these changes for viewing later (see the image below). The system makes a copy of the record prior to the change and stores it along with the change date, the user making the change, and the change actions (insert, update, and delete).

Comparing the Resource History record dated 4/1/2008 (equipment = SX135321, resource = L2K) with the current equipment resource list on the Resources tab of PM Schedule the user SDS deleted resource L2K for equipment SX135321.

Resource change history can be viewed at any time by clicking the View Resource History link button (see below).

The Refresh Resources link can be used to repopulate resources that are currently related to one or more PM schedule equipment. This is a convenient way of obtaining the latest equipment resource information if one is aware that it has been updated since the equipment was related to the PM schedule.

Following the PM schedule setup tasks mentioned above, the Maintenance Planner can now generate preventive work orders based on equipment PM schedules. In addition, breakdown work orders will be created on an as needed basis for any unplanned work. The following image shows a list of both preventive and breakdown type work orders that the Maintenance Planner must schedule and execute.

Resources impacted by the work order, by default, will be either be pulled across from the related PM schedule or from the equipment itself depending on whether the work order is classified as preventive maintenance or breakdown. Resources for unplanned (non-PM) work orders can be changed by the Maintenance Planner for the work order if necessary.

The system protects the work order resources tab on planned work orders. Data cannot be inserted, updated, or deleted for these work orders. However, if a change is made to the resources of the related PM schedule the system will automatically synchronize these changes with all open work order for the PM schedule.

The following image shows a list of work orders for both preventive and breakdown maintenance. WO 10010 will impact ERP resources because as shown in a previous image of the PM Schedule, resources are related to equipment SX135321. In contrast, WO 10015 will not impact resources because this is a breakdown work order, and the equipment has no resources associated.