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Motzener Kunststoff- und Gummiverarbeitung GmbH

An Interview

Motzener Kunststoff- und Gummiverarbeitung GmbH, a company rich in traditions, is making the largest single investment ever in its long corporate history in today's troubled economic environment. The purchase of a special machine for producing large seals enables the company to expand its existing areas of activity and pave the way for new orders.

DESMA collaborated with this producer of special seals to develop and optimise a special machine for a special product group. The new machine has been commissioned in October 2009 and thus a report and summary of the collaborative development work is now possible. In talks with the two company owners Mr Thomas König and Mr Bernd Moos, we looked at the various milestones of the development phase through to the machine's production start-up in Motzen (near Berlin).

DNR - Team:

Please tell us something about your company's history.

Thomas König:
The company was established in 1931 by Hermann Buchholz, a Berlin entrepreneur, and has always specialised in the manufacturing of plastic components.

DNR - Team:

How did you get to your present location in Motzen?

Thomas König:

Mr Buchholz already had a company in Berlin. Even in those days, personnel costs were a key factor in deciding to establish a subsidiary operation outside of Berlin. The location of Motzen offered ideal conditions, since it also had rail access. At that time there was also an empty building available, the premises of a former cheese dairy.

DNR - Team:

What is today's ownership status?

Thomas König:

I have been with the company since 1974, and purchased the plant in Motzen from the trust organisation in 1993 together with Mr Bernd Moos.

Machine pre-acceptance at DESMA

DNR - Team:
In which industrial sectors do you work?

Bernd Moos:

Our largest sector is our seal division, involving the production of high quality special seals of up to 1,600 mm diameter for vehicles/machines in the agricultural and building machine sectors. This includes in particular mining and materials handling technology.
Another crucial pillar of our activities covers articles for mechanical engineering and apparatus engineering. One of the focuses here is high-quality technical seals in the two component segment.

DNR - Team:

How has your company been impacted by current economic developments?

Thomas König:

Obviously, our business volume fell during 2009. We were, however, able to use short-time working and early retirements to avoid any redundancies and still employ a workforce of 58. We expect a further recovery in 2010.

DNR - Team:

How long have you been working together with DESMA?

Bernd Moos:

In effect, since 1990. Even while the trust organisation was still in charge, we invested in second-hand plant from DESMA. In 1996 and 2000 we purchased further DESMA machines.

DNR - Team:

In 2008 you also decided to buy a special machine from DESMA for the manufacture of special seals of up to 1,600 mm diameter. This special unit was developed to meet your application requirements. Two movable injection units are able to produce different article diameters with a minimum of runner waste and without the need for cold runner technology. How would you assess the development work between your team and DESMA?

Thomas König:

At that time we had taken an early look at the technical feasibility in detailed talks with DESMA. This produced a number of different options which were finalised in a kind of knock-out procedure until we reached the current machine concept, reflecting all existing experience from previous productions.
The collaboration was smooth and efficient throughout the entire development and realisation phase.

DNR - Team:
The machine was delivered and installed in your new workshop in mid-October after 10 months of development and building. Has the machine satisfied your expectations in terms of product quality and capacity?

Bernd Moos:
As far as product quality is concerned, it has totally confirmed all of our expectations. Even large HNBR 50 seals have absolutely no blisters, no blow wholes or layering. Thanks to the two movable injection units the wastage is 6 - 8 g for an injection volume of almost 1,700 cc. That is an excellent result. As far as quantity is concerned, it is too early now for final conclusions but we expect to be able to cut the heating time in half compared with the previous compression moulding method.

DNR - Team:
The machine features a new development in heating plate design, configured to achieve maximum energy savings while allowing a variety of mould sizes. Only those areas are heated which are covered by the mould (ring moulds). The non-activated sections are for the most part thermally insulated. How has this technological development proved itself in practice?

Bernd Moos:
The anticipated advantages are exactly as expected. Depending on mould size, up to 50 % of the normal heating capacity is able to be saved. In the case of heating plates of 1,700 mm diameter, that is a major savings potential.

DNR - Team:
The mould carrier was the subject of high precision design calculations to achieve best possible clamping force development around the article area. The calculations used the Finite Element method to precisely predict the clamping force allocation using a pressure adapter plate. The target was to distribute a relatively low clamping force of 6,300 kN over a heating plate of 1,700 mm diameter as evenly as possible. What is the result in terms of flash?

Bernd Moos:
In short, we now have a system for the low-flash production of large diameter seals. As a result of this, our expectations have been fully satisfied here again.

DNR - Team:
Do you offer production capacity to third parties? After all, machines which are capable of producing seals of diameters up to 1,600 mm are few and far between.

Thomas König:
That is a definite affirmative! That was also one of the reasons for making this investment decision. We intend to grow further in the field of special seals and are naturally very much interested in collaborating with other seal manufacturers, also with respect to other products which require machines of this type.
The machine and its two injection units are suitable for all standard types of rubber and also comes equipped with silicone stuffer system to process HTV silicone.

DNR - Team:
Where exactly are the main benefits for you in moving from compression to injection moulding of large seals?

Bernd Moos:
One effect is obviously reducing the cycle time. But there is a further effect in that it waives the need to prepare the raw materials ready for compression. As a certified company, (DIN ISO 9001, TS 16949) we are also able to avoid many intermediate processes requiring compulsory documentation. In this case we have the starting incoming material and then the final product, this has the effect of making the entire production process much leaner.
I think the decisive factor for our customers is the drastically improved product quality for the same money. This secures competitive advantages both now and in the future.

DNR - Team:
What are your plans for 2010?

Thomas König:
We are expecting to see further market recovery. We think this new investment will gain us additional orders and also an increased market share. The new machine means we have a genuine USP in the entire industry. Together with our in-house mould shop we are very well positioned.

DNR - Team:
Thank you very much for talking with us, and we wish you continued success in the future.

Final acceptance of D 968.600 ZO/ZO special machine
View of giant mould carrier with clamped mould