Improving delivery reliability and lead time with Siemens solutions

Founded in 1965, SUMIDA Lehesten has more than half a century of experience specializing in electronic manufacturing services(EMS). The company’s longstanding customer base includes clients from the fields of automotive, medicine, industry, measurement and testing technology,
communication and consumer electronics.

Leading-edge production facilities and a well-coordinated team of employees make SUMIDA Lehesten a leader in assembly of printed circuit boards. The company uses both surface mount and through-hole technologies to produce electronic assemblies and devices, and also offers painting, coating, electrical testing, assembly and logistics services. As part of the globally active SUMIDA AG, with approximately 21,000 employees and an annual revenue of more than €770 million, SUMIDA Lehesten is a stable business partner.

In addition to electronics manufacturing services, SUMIDA Lehesten offers prototyping,
selective soldering, components management and International Material Data System
(IMDS) services.

Broad product portfolio challenges planning and scheduling

SUMIDA Lehesten’s broad product portfolio adds complexity to the planning and scheduling of electronics manufacturing operations. The focus of the project was the Lehesten site, which manufactures approximately 150 different assemblies per month. Around 3,000 processes per month must be coordinated and planned in compliance with the target dates. Despite many years of experience, a lot of process knowledge and many buffers in time and material, planning of these complex processes was insufficient. In addition to a high material inventory, the planning led to frequent delivery delays because the wrong processes were carried out at the wrong time.

In the past, SUMIDA Lehesten planned its production operations based on spread-sheets, meeting notes and other personnel input. Planning required a great deal of manual effort. This approach had little transparency and hindered a common understanding of priorities and bottlenecks, often resulting in capacity overloads in production.

The company used its already implemented enterprise resource planning (ERP) system for production planning and scheduling. With limited planning logic, the ERP system did not provide an accurate overview and transparency and could not effectively coordinate the manufacturing departments. This resulted in poor adherence to schedules and too much manual effort in planning.

SUMIDA Lehesten aimed to improve planning and scheduling using its enterprise resource planning (ERP) system in conjunction with the Opcenter™ Advanced Planning and Scheduling (APS) solution, part of the Siemens Xcelerator business platform of software, hardware and services. The goal was to adopt proactive and forward-looking planning to replace short-term, reactive planning.

Developing a solution with an expert partner

SUMIDA Lehesten partnered with MCP, a Siemens Expert partner specializing in Opcenter APS, in a project to develop an innovative solution to address these problems and improve key performance indicators (KPIs). Opcenter APS offered sophisticated planning logic that provided a more realistic model of shop floor operations and recognized actual plant capacity limits in real time.

SUMIDA Lehesten and MCP introduced a more precise and intelligent planning logic using Opcenter APS. Instead of considering production orders in their entirety, planners used Opcenter APS to examine each work step individually, calculating start, end and throughput times depending on the lot size. Planners use the software to accurately determine the critical ratio – the remaining time to due date divided by the shop processing time that is still available. The critical ratio provides a clear indicator of the status of each process (ahead of, behind or on schedule) that guides planners in prioritizing job orders and making resource adjustments to address bottlenecks. Planners can also adjust schedules manually if necessary.

Carefully planned implementation

For the implementation project, MPC and Sumida Lehesten established a link between Opcenter APS and production workstations and automated report creation and printing to make the product plans available to the workstations. The reports list all of the machines and equipment on a daily basis, separated into early, late and night shifts, with planned production orders including all
related information. Progress reports of each production order are now visible to the planning department, drastically reducing the planners’ workload, since control during production is no longer necessary.

“Successfully implementing a solution like Opcenter APS requires not only software customization, but also requires a partner who understands the existing business and can assist with the necessary organizational change,” says Markus Herckner, Controlling, SUMIDA Lehesten. “MCP has these competencies.” Additional requirements that arose during the course of the project could be
easily integrated thanks to the systematic implementation methodology.

Ease and flexibility

Opcenter was a good fit for SUMIDA
Lehesten. “With Opcenter APS we especially
liked the easy connection to our existing ERP
system,” says Herckner. “Furthermore, many
adjustments can be realized directly in
Opcenter APS with little effort. Using our
ERP system’s planning and scheduling tools
would have been much more complex and
therefore more costly.

”Opcenter APS helps optimize lot sizes based
on the availability of employees and systems
to make the best possible use of capacity.
These complex rules improved the overall
system effectiveness of the site.

Realizing benefits

“The successful implementation by MCP and
the positive impact of Opcenter APS have
convinced the management of SUMIDA
Lehesten to continuously implement new
developments within the program,” says
Daniel Walkiewicz, partner and project manager, MCP. The business benefits include a
35 percent increase in delivery reliability,
from 60 to 95 percent. Lead times have
been reduced from 20 days to five days, a
75 percent reduction.

“Before we implemented Opcenter APS, our
production planning was based on Excel
lists, meeting minutes and personal notes
from employees,” says Herckner. “With
Opcenter APS we have a common database.
This makes the entire manufacturing process transparent. If we have a common
understanding of which orders are really
important or where bottlenecks exist, we
can take appropriate remedial action earlier,
faster and in a more targeted manner.
Improving delivery reliability is then a logical
consequence.”

“By using Opcenter APS, many discussions
regarding production planning and control
can be significantly shortened,” says
Herckner. “The increase of delivery reliability
and the reduction of lead times are points
from which our customers directly benefit.
The reduction of internal effort while
increasing the service level increases our
competitiveness.”

All of these improvements have resulted in
the new planning solution gaining trust
among SUMIDA Lehesten employees and
increasing their satisfaction. Instead of
working with two systems, all production
plans are now created in Opcenter APS. The
relevant performance indicators, such as
inventory levels, productivity and work in
process, have been significantly improved
because Opcenter APS optimizes utilization
and less time is lost due to constant
changes.