Customer Name: An export oriented foundry near Pune, India
Focus: Just-In-Time maintenance
The customer is an export oriented foundry near Pune.
Overall business requirements of customer are outlined below. But this case study discusses only about maintenance module
- Loss analysis
- Production monitoring - OEE
- Just-In-Time Maintenance (discussed in this case study)
Customer has several special purpose machines (SPM) which perform multiple assembly operations on a component. Machines work very fast and 5-6 operations are completed in total 2 to 3 seconds. There are many moving parts and there is wear and tear of these parts over a period. If any of these parts are not in proper condition, errors occur during operation and machine halts. Then the operator has to correct the error and restart the machine. This wastes lot of time and results in performance loss. To avoid this, maintenance team would replace these parts aggressively (earlier than needed). For example motor brush should be changed after every 3000 hours of running. Assuming machine runs 7 hours per shift x 3 shifts x 6 days a week; brush should be changed after every 23 weeks. But many times, the machine would run only for 2 shifts. Also per shift running may be less than 7 hours due to various reasons. But it was impossible for maintenance team to track this and hence they changed brush every 23 weeks. One single machine has 30 parts that need periodic replacement and some of the parts are quite expensive.
Customer has several Die Casting machines which run continuously without any break. These machines are shut down periodically for maintenance and parts replacement. However, many times some issues develop in machine condition which cause reduction in efficiency as well as deterioration of product quality.
There are common utilities which are shared by multiple machines namely furnace for die casting machines and air compressor for SPM. Condition monitoring of these utilities is very important as their failure will affect all dependent machines.
PlantConnect SFactory Solution
Maintenance Module of PlantConnect SFactory provides concise workflow to drive asset maintenance.
The module is setup as follows to solve business challenges mentioned above.
Running Hours based Parts Replacement
- To ensure Just-In-Time parts replacement, Running Hours based maintenance alerts considering appropriate lead time are defined for each part
- When an alert occurs, it is sent to maintenance, stores, production by SMS
- Maintenance of the machine is planned. At this time, system advises for any other impending alerts so that multiple maintenance can be combined
- SFactory monitors few critical parameters like melting temperature, injection pressure, die temperature as well as injection time, cooling time etc.
- Conditions are defined in CBM module to monitor critical parameters and their effect on process efficiency and product quality
- These conditions are evaluated in every cycle
- There are no sensors on furnace which can be read by SFactory. So in order to do JIT maintenance, conditions are defined using production of all machines that use same furnace.
Benefits after SFactory implementation
PlantConnect SFactory installation was completed in Oct 2017. It is too early to quantify monetary returns as enough data is not yet available. This case study will be updated once we get enough data. But the solution is definitely helping and some concrete results are visible like
- Just-In-Time parts replacements is pushing the replacement schedule ahead without affecting machine performance. There by same parts are getting used longer. This will result in cost savings.
- There is improvement in efficiency and product quality due to CBM of die casting machines
- JIT maintenance of furnace and compressor