We are Sonplas.

Founded in 1993, Sonplas, based in Straubing, is an established special-purpose machine manufacturer with nearly 400 employees in Germany and two subsidiaries in China and the USA. We develop flexible and scalable solutions for machining, assembly and testing – true to our guiding principle: “For your success.”

Special-purpose machines are driven by individual requirements – and this is exactly where Sonplas excels. We develop and implement systems that are precisely tailored to the respective application and customer needs.

TOP-Unternehmen Niederbayern Auszeichnung

Sonplas at a glance.
What sets us apart.

We are a trusted partner to our customers, drawing on over 30 years of expertise to develop solutions that meet the highest technological and quality standards. At Sonplas, partnership, innovative strength and deep technical understanding come together.

We strive to understand processes from the ground up and prefer to develop them in-house – supported by our own research and development as well as around 200 engineers. A key strength valued by our customers worldwide: more than 1,000 machines and systems successfully deployed across a wide range of industries – from aerospace and defense, mobility and medical technology to consumer goods and power tools.

From the initial idea to after-sales support: we are at your side.

Support starting from product development
Consulting, planning and project engineering
Mechanical and electrical design as well as fluid engineering
Manufacturing and procurement
Assembly and installation
Commissioning and validation
Training
Service
Retrofit

With our comprehensive range of services, we ensure that customer projects are developed and implemented in line with Design for Manufacturing, Design for Cost and Design for Testing principles. We actively contribute our expertise from an early stage and support you already during product development to achieve the best possible outcome.

This consistent approach results in shorter development cycles, stable and reproducible processes, as well as higher quality at reduced costs.

Learn more about how we work

Good reasons to choose Sonplas.
Solutions that deliver.

Over 30 years of experience

Since 1993, we have been developing customized special-purpose machines for a wide range of industries.

Excellent engineering expertise

Our technically skilled sales team and experienced enginnering ensure well-designed and efficient systems.

Everything from a single source

Whether prototype validation or series production, we support you from the initial idea through to lifecycle management.

Projects up to ~ 15 Mio. €

We deliver projects from test cells to full production line optimized both technically and economically.

Family-owned

We make decisions with a long-term perspective and focus on stability, reliability and continuity.

Locally rooted, globally connected

Our trained sales and service partners ensure fast and reliable support worldwide.

Expertise
you can rely on.

Our expertise covers all key disciplines: mechanical design, software, process development, simulation, integration and assembly. These areas are seamlessly integrated at Sonplas, enabling solutions that are not only technically advanced, but also economically efficient and designed for long-term success.

We continue to support our customers even after commissioning: to ensure fast response times worldwide in service cases, we operate our own locations in North America, India and China, complemented by a global network of service partners. Our partners are carefully selected and comprehensively trained at our facilities, ensuring they are fully qualified to maintain and service your equipment. You can rely on consistently high quality and outstanding technical expertise.

Sonplas: Yesterday. Today. Tomorrow

Over more than 30 years of company history, you don’t just accumulate successful projects and awards, but also a number of significant milestones. Join us on a journey through the history of Sonplas.

Founding

Following the bankruptcy of their former employer, our shareholders were given the opportunity to complete an outstanding customer project. With a service contract that also covered their initial salaries, the five supported the system and ultimately decided to establish their own company.

On April 15 1993, our founders Herbert Frankl, Hermann Pankofer, Rudolf Raith, Walter Bumes and Christian Ludwig signed the shareholder agreement for Sonplas GmbH – laying the foundation for the company’s success story.

From the very beginning, they placed great emphasis on providing their customers with a holistic and partnership-based approach, addressing all requirements in the best possible way – a principle that continues to shape our company to this day.
Development of an adjustment module for an injection valve for cars

With the AFM (Active Flow Meter), the founders achieved an early milestone that provided Sonplas with a unique selling proposition and attracted numerous customers. The key innovation: this advanced assembly efficiently combines high-pressure generation with precise flow measurement.
First class starts their apprenticeship

Getting capable young people excited about the future of the company and ensuring that they receive professional training has been on Sonplas’ agenda since 1996. Since then, an average of ten new trainees start their careers every year.
Development of a “hydroerosive grinding process”

Sonplas lands another success with hydroerosive grinding. Here, the company establishes another unique selling point in the field of deburring, rounding and flow calibration. Using an abrasive fluid in varying degrees of fineness, internal burrs can be smoothed and bore intersections rounded.
Moving into the new Sonplas company building

Shortly after the original building was constructed in 2001, the first expansion was already underway — an extension to the existing production hall. Sonplas moved into this extension in 2008, which, together with the original building, is now known as Plant 1.
Global implementation of the HE grinding process & entering the pump testing market segment

The development of hydroerosive grinding has far-reaching consequences – positive, of course – as the grinding process enables Sonplas to build up a global customer base. At the same time, Sonplas enters the field of pump testing, thus expanding its product portfolio.
Establishment of a Sonplas service department

To ensure fast and reliable support in service cases – both on-site and remotely – Sonplas established its dedicated service department in 2009. Today, Sonplas operates a global network of trained service partners, ensuring short response times and competent support worldwide.
Entry into the “e-mobility” sector

Actively shaping the future of mobility? Sonplas is succeeding in this with its entry into e-mobility. Initially, the focus is on assembly systems for rotors and stators, soon followed by the expansion of competence for assembly and testing technology in key production, for inverters and EMC filters as well as other powertrain components.
20th company anniversary

The first 20 years are up sooner than expected and Sonplas is celebrating its birthday. The company’s balance sheet: positive throughout. Healthy growth and a unique cohesion among the employees form the basis for the coming events.
Entry into the “aerospace” sector

The next addition to the portfolio is the entry into the field of ” aerospace technology”. Here, the focus is primarily on systems for the hydraulic and pneumatic testing of components. In concrete terms, this means: maintenance of aerospace equipment, radiation image measurement, functional testing of pumps and pneumatic pressure testing of pipes.
Construction of the new production hall begins

2017 will see the start of construction of Plant 2, directly opposite the first plant. From 2018, our customers’ systems will be developed and manufactured on a further total of around 6000 square meters of production space.
Official opening of the new production hall

The new hall is completed in time for the company’s 25th anniversary. With the inauguration of Plant 2, there is now just under another 9600 square meters of office and production space available.
Entry in the field of “battery cell production”

The battery product area is another innovation key driver at Sonplas. In the field of laser notching, i.e. the laser-assisted cutting of electrode material for batteries, Sonplas can draw on its extensive knowledge and experience in laser cutting processes. These competencies can also be applied to battery technologies such as pouch cells, solid-state or redox flow. Other technologies, e.g. for stacking the electrode material, are currently under development.
Entry into the “medical technology” sector

With its first order in the medical technology sector, Sonplas consistently continues its transformation process. What had already been demonstrated in individual projects is clearly confirmed by this milestone: the expertise gained from nearly 30 years of automotive projects can be successfully transferred to other industries, forming the foundation for a broad and diversified solution portfolio.
Entry into the “hydrogen” sector and first customer projects

In 2022, the in-house test center for hydrogen-related components in engines, fuel cells and electrolyzers was commissioned. In the third quarter, the first customer projects started, focusing on testing this forward-looking energy source.
30th company anniversary, expansion of the board of management & purchase of factory 3

The year 2023 was marked by several significant milestones: alongside the company’s 30th anniversary, Herbert Frankl retired after three decades in management and handed over the executive leadership to Michael Frankl and Christian Wachtmeister.

With the acquisition of an existing building for the future Plant 3, Sonplas continued its expansion in 2023. The new facility will house the IT, software and service departments.

At the same time, the company successfully expanded its expertise into additional industries. With the first project in the consumer goods sector, Sonplas laid the foundation for numerous further orders in this field.
Foundation of Sonplas Automation (Kunshan) Co., Ltd. and entry into the “defense and security” sector

After more than 20 years in the Chinese market, Sonplas Automation (Kunshan) Co., Ltd. was established in 2024 to be even closer to local customers and to further enhance service capabilities. The new sales and service location in Kunshan ensures optimal coordination of business activities and provides customers on site with continuously improved support.
Founding of Sonplas USA Inc. and first projects involving methanol and ammonia

With its second subsidiary, Sonplas USA Inc., Sonplas is further strengthening its customer focus in the U.S. market after decades of successful project execution. The new location in Chicago handles local sales and technical service. Customers benefit from fast response times, close coordination, personal support, as well as on-site assistance for commissioning, upgrades and training.

In 2025, Sonplas also successfully completed its first customer projects involving the testing of components with methanol and ammonia. This further expands the company’s expertise in fuels and media by adding two additional test media.

Your project,
our core competencies

Sonplas covers a broad range of turnkey system solutions used by our customers for the development and series production of technical components and products. This includes high-precision testing and inspection systems that evaluate component quality using advanced measurement technology, sensor systems and software. In addition, we develop customized assembly and machining systems that ensure stable and reproducible processes – even with increasing complexity, delicate components and tight tolerances. We also collaborate closely with our customers on new developments. Our innovations include, for example, test rigs for shock absorbers, our hydrogen test center, as well as advanced processes such as cold and hot joining, micro peening, hydro-erosive machining, vacuum enthalpy cooling and additive balancing.

Our team makes the difference.

Our success is driven by a strong team: engineers, technicians, project managers and specialists from a wide range of disciplines working hand in hand to deliver solutions that excel in every detail.

Each system reflects the knowledge, experience and passion our employees bring to their work. We believe in openness, mutual trust and efficient communication. This culture not only shapes our internal collaboration, but also our interaction with customers: we see ourselves as a partner who listens, challenges ideas and works closely with all stakeholders to develop the best possible solution.

This spirit of collaboration is one of the key reasons why many customers have trusted us for years and continue to rely on us for their most demanding challenges.

More insights into our corporate values