Lakshmi Precision Screws Limited (LPS) manufactures metal fasteners, bolts and screws, with a diameter ranging between 3 and 36mm and lengths 5 to 1500mm. There are also different thread specifications, raw materials and finish specification resulting in around 8500 varieties. Based in Rohtak, 60km from New Delhi, India, LPS has two manufacturing units spread across 100,000 sq.m and must plan production up to three months ahead. The manufacturing process starts by cold heading in transfer machines followed by threading, grinding, other supplementary operations, heat treatment (in several stages) and finishing.
The first operation has a long setup time and very short run time while the second operation has quite the opposite attributes. The production batch for the first operation is thus necessarily large and then split into smaller sub-batches for subsequent operations. In heat treatment the requirement is to maximize the utilization of oven space yet minimize queue time so it is necessary to apply load minimum and maximum size to achieve this compromise. A similar complexity exists in finishing processes such as zinc plating, phosphating & oiling, blackening etc.
LPS have to provide both a Make-to-order service for specific customers as well as make-to-stock for the general retail market. Orders from customers have a high priority and often have tight delivery deadlines while make-to-stock items are treated differently. Before the introduction of Preactor, LPS used a manual system to plan production because their SAP R/3 system did not provide the functionality they needed to manage production at a detailed level. However the manual system was not able to cope with sudden order changes which needed staff to carry out tedious calculations and expediting at shop floor level.
This often led to an increased work load for operators, lengthy throughput times, large amounts of work-in process and poor delivery performance. It was not possible to follow up regularly to ensure that the delivery targets could be met.
LPS recognized that they needed to have a tool to overcome these problems. One that could operate both stand alone or integrated with SAP R/3 and one which could schedule up to 900 resources with up to 150,000 orders each with up to 15 process steps in a few minutes. An evaluation of various packages was carried out by LPS PPC & SIG Departments the result of which was to recommend Preactor. The advantages of Preactor over competitive products identified were:-
- Fast schedule generation
- User friendly GUI for example the drag and drop capability
- Easily configurable multi-pass scheduling rules that could handle the complexity of the LPS production environment and match their own business rules
- Expert local support available
In view of the extensive complexity in business and production requirement, it was necessary to generate a heavily customized configuration of Preactor APS. This was done by ABCON Information Systems and support from Preactor International. As Preactor is a rule based scheduling software, ABCON were able to experiment with different rules and check the levels of performance through measuring key performance indicators (KPIs) and in this way choose what was optimal for LPS. Reduction in setup time was the focus for the primary operations while the need for subsequent operations up until tempering was very different.
Another rule logic was used for furnace loading and yet another for post heat-treatment processes. This needed complex multi-pass rules that met all the needs of each part of the process for LPS.
In late 2004 the system went live. LPS is using Preactor APS regularly in generating schedules, working to schedules generated and getting the feedback from the shop floor on performance against planned schedules. In generating schedules Preactor takes stock of finished goods first and then WIP into account, so that production is scheduled with minimum inventory of both finished goods and WIP. And some surprising benefits have already emerged.
Before introducing Preactor, there was a target to transmit data once per week from the Legacy System. The plan was to improve it first to a one-per-month level, and then progress to the one-per-week. However, plant changes delayed this process. But to everyone's surprise, Preactor was useful in simulating the plant changes before they were completed and in addition the following benefits have already accrued:-
- Scheduling could be carried out on the fly and any changes to the schedule could be easily communicated to the shop floor.
- Improved visibility of the current production load enabled LPS to commit to delivery dates with confidence.
- Ability to schedule and control production, so that the plans are monitored and maintained thereby avoiding time over runs.
- Considerable reduction of inventory of finished goods and WIP.
Mr. L.K Jain, CMD of LPS and his production team are satisfied with the performance of Preactor with respect to scheduling and would like to extend it to cover its tool room in the future. Also they want to utilize the additional functionality in 9.3 to provide a Capacity Planning tool for use by their marketing people to have better visualization of all the three plants weekly capacity while accepting customer orders.