Our Company

High Profile and Experience.  A Background with Long Tradition.

Jünger+Gräter is a modern company operating worldwide. We can look back on 80 years of successful operations. We see ourselves as trendsetter in the industry and maintain our leading position among international competitors.

Agility and creativity are the basis of our everyday actions. This ensures the highest degree of flexibility to the benefit of our customers. This enables us to proceed with such distinctiveness when providing specific solutions leading to optimal results.

Our innovative strength creates new ideas and our level of performance generates new forms of implementation. This has always made Jünger+Gräter distinct. Our customers can rely on this today and tomorrow.

More than 80 years of Experience

1936 - 1965

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Josef Jünger, Firmengründer im Jahr 1936 Porträt


Josef Jünger founds the company "A. & J. Jünger OHG Feuerungs- und Schornsteinbau" together with his brother Adam in Mannheim, Germany.

The big power plant Großkraftwerk Mannheim (GKM) was one of the company’s first customers. This company still takes advantage of the reliability of J+G today. Two years later a patent was filed with the German Reich Patent Office for the JJ suspended roof. This underscored the innovation and Jünger’s foresight to protect his inventive know-how against copycats.

Fritz Gräter Senior Porträt


Fritz Gräter sen. joins the company. He marries Leni Jünger, the daughter of Josef Jünger, in 1941.

Unternehmenssitz in Schwetzingen


Josef and Adam Jünger separate. The company moves to Schwetzingen and changes its name to "Josef Jünger Feuerungsbau und Ingenieurbüro".

Old documents show how hard the times were during the last years of World War II and first years after the war. For example, only 10 design (construction) drawings were made in 1945. This means that business activity was down by 80% compared to previous years and proves how big the economic difficulties were at that time.

Bauarbeiten der Schmelzkammer-Kesselanlagen in Mannheim


With the construction of the four melting chamber boiler plants for the GKM power plant in Mannheim one sees signs of the economic recovery for J+G and Germany. The order was placed by Kohlenscheidungs-Gesellschaft (KSG) in Stuttgart which is now known as Alstom Power Systems.

Ofen mit Wirbelschicht-Düsenboden


First orders are received from customers outside Germany. These customers are located in Switzerland, England and the Netherlands. The engineering office Raschka in Heidelberg requested J+G to install the brickwork lining in the first furnaces with a circulating fluidized bed. These furnaces were the foundation for the J+G success story in the sector of circulating fluidized bed incineration as an inventor of many new developments in and around CFB technology. Many of these inventions are still in use today.

Bau eines Zick-Zack Ofens


Company moves to new offices in the Kurfürstenstraße 24 in Schwetzingen.

Business grows and a big order is received to build a so-called zig-zag furnace for the tile manufacturer Hensieck in Velpe/Westphalia. More than 100 J+G bricklayers worked at the biggest construction site J+G had served up until this date. The photograph shows from right to left: Stefan Schuhmacher as construction manager, Josef Jünger and Fritz Gräter.

Bauzeichnung eines BASF Einrohrkessels


Order placed by KSG for boiler no. 9, Kraftwerk Mitte of the BASF chemical company in Ludwigshafen. The order value was DM 278,000.00. A bricklayer earned DM 2.36 an hour. Today the order value would be about €2 million and a specialized refractory bricklayer earns €16.93 an hour. This corresponds to an annual inflation rate over 5 % over 56 years or a total inflation rate of approx. 1,300, % until today.

Jünger und Gräter Logo von 1958


New company name Jünger & Gräter KG, General Partner: Fritz Gräter sen.

More office space leased in the Kurfürstenstraße 22a in Schwetzingen.

Big KSG order for a lignite boiler with a thermal performance of 1,000 tons steam/h in Ptolemais, Greece. Followed by Kardia (2x), Agios Dimitrios (2x) both in Greece and Neyvelli (4x) in India. With Block Q in Frimmersdorf, Blocks A, B and C in Neurath lignite boilers are lined with refractories and serviced in Germany, too.

Ausbilder Karl Träger im Sudan


Fritz Gräter joins the company as refractory bricklayer apprentice in his second year of training.

J+G’s first big project outside Europe: Sugar plant in Guneid in Sudan. Four steep pipe boilers with bagasse firing are built for the machinery company Buckau R. Wolf AG in Grevenbroich/Neuss. Our former refractory bricklayer apprentice and later foreman, Karl Träger (photograph), was also active there as training supervisor.

Schornstein des Müllheizkraftwerks Mannheim-Nord


Jünger+Gräter Beteiligungs-GmbH becomes General Partner. Total capital: DM 100,000.00. Josef Jünger and Fritz Gräter sen. are the executive managers.

Construction of the last chimney bricked by J+G with a height of 150 meters for the refuse incinerator Mannheim-Nord which is still in operation today. In the mid-1960s, J+G discontinued chimney construction activities because of now specializing on the slip-forming method in the chimney construction sector.

Feuerfeste Auskleidung einer Müllverbrennungskammer


Start of the main business activity of J+G: waste incineration. J+G got the order for the refractory lining inside four plants for the City of Mannheim on the Friesenheimer Insel. This was one of the biggest plants in Europe with an incineration capacity of 125,000 tons annually.

Neuer Leiter der technischen Abteilung: Josef Kandziora


The company founder Josef Jünger dies at the age of 74. Josef Kandziora takes over the technical department.

Construction of the first special refuse incineration plant at the BASF chemical company in Ludwigshafen. This project paved the way to become a recognized refractory engineering partner in this special field of environmental protection and connected thermal processes. Since this time J+G is a renowned partner when it comes to solving difficult problems in the sector of refractory engineering.


1966 - 1992

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Betriebsgebäude in der Robert-Bosch-Straße 1


Company moves into the Josef Jünger House in Robert-Bosch-Straße 1 in Schwetzingen. Fritz Gräter becomes the second executive manager.

Installation of a dome without using molds at the Farbwerke Hoechst chemical company in Frankfurt-Höchst. This technique developed by J+G was a milestone in the construction of circulating fluidized bed plants. Plants were built outside Europe in Zambia, Peru, Algeria and Australia. A zinc roaster has the diameter record for a self-supporting crown with over 16 meters at Asturiana de Zinc in Spain.

Zeichnung einer Wirbelfließanlage für BASF


First order over DM 1 million – exactly DM 1.61 million – for a new process called “circulating flow plant” at the BASF chemical company in Ludwigshafen. J+G installed more than 1,300 tons of standard and shaped refractory bricks because BASF did not accept unshaped refractory materials (monolithics) at that rime. To better grasp the magnitude of this order one has to know that the total sales volume of J+G was 3.6 million the year before (1967).

Pelletieranlage mit Stahlbau


Completion of the second administration building, workshops and storage facility. Stefan Schuhmacher is appointed to Chief Engineer.  

Speedy transformation from a craft business to an internationally operating refractory engineering company. As part of the booming steel industry J+G obtained big business by constructing pelletizing plants. One of the first plants was built completely with steel construction and refractories in Vitafors/Sweden. The order was placed by Lurgi Chemie und Hüttentechnik GmbH and worth DM 2.51 million.  Projects in Brazil, Venezuela, Mexico, India, Nigeria and Libya followed.

Patenturkunde für freitragende Düsenböden aus feuerfester Stampfmasse


Introduction of data processing in the commercial sector.

Filing of the patent “Self-supporting, ceramic tuyere bottom out of refractory ramming mix with tuyeres positioned in the bottom”. The tuyere bottom is operated with hot air coming from below and was mainly used in sewage sludge incinerators or metallurgical roaster plants. Due to its design and robust build the “J+G tuyere bottom” became an immediate success and was a synonym for the inventiveness of J+G. This J+G premium product operates in over 200 plants around the world.



After restructuring the business is conducted by “Jünger+Gräter GmbH Feuerfestbau“. Share capital: DM 600,000.00.

Starting with the construction of an aluminum oxide calcining plant based on a circulating fluidized bed in Nikolajew/Ukraine the foundation was laid for further plants in Germany, Australia, USA and France. J+G was able to gain the lead in know-how in this field.

Leiter der kaufmännischen Abteilung, Urban Butz


Urban Butz became head of the commercial department.

Start of business involving direct reduction plants for iron ore with projects for Lurgi and Voest in  Hadeed/Saudi-Arabia, Misurata/Libya, Auckland/New Zealand, Vanderbijlpark/South Africa and the Malaysian Federal State Sabah on Borneo.

Innenansicht eines zirkulierenden Wirbelschicht-Kohlekraftwerks


Foundation of the subsidiary “Socoré S.à.r.l.“(Société de Constructions Réfractaires), nowadays ”Jünger+Gräter SARL“ in France.

Due to their big experience with calcining plants J+G becomes a pioneer in the refractory sector for the construction of circulating fluidized bed coal power plants. Together with Lurgi Energie und Kohle GmbH a new highly efficient and environmentally-friendly energy generation technology (from coal) was first implemented.

Neuer Geschäftsführer Fritz Gräter Junior


Fritz Gräter sen. departs as the executive manager. Fritz Gräter becomes the sole executive manager.

Neuer technischer Direktor, Dr. Ing. Ehler Nowak


Josef Kandziora departs the company as technical director. Dr. Ing. A.-Ehler Nowak is his successor.

J+G is the largest refractory engineering company in the National Association of the German Construction Industry (ZDB) and a leading founding member of the German Association for Refractory and Chimney Engineering (dgfs). The first meeting of the governing body was held in the hotel Bayrischer Hof on October 15, 1985, in Munich. Fritz Gräter was elected as Vice-Chairman of the German Association for Refractory and Chimney Engineering.

Brennkammer einer Clausanlage


50th anniversary of J+G.

J+G gets the order to build the worldwide biggest Claus plant (sulfur generation out of coke oven gas or natural gas) in Tengiz/Kazakhstan. The diameter of the combustion chamber and, consequently, the tuyere bottom is over 5 meters.

Erster Jünger und Gräter Report


First meeting of 23 J+G retirees. This was mentioned in the first J+G Report with a content of 12 pages.

J+G entered a new entrepreneurial sector with the construction of the first weapon disposal plant in Munster. For the first time J+G acted as “plant engineer“. J+G supplied all required components for the furnace including the control unit. Due to the disarmament treaties between the USA, European Union and the Soviet Union further plants of the same type were also built by J+G in Russia.

Innenansicht einer Klärschlammverbrennungsanlage bei BASF


Construction of the worldwide largest sewage sludge incineration plant for the central sewage plant of the BASF chemical plant in Ludwigshafen with major assistance on the part of J+G.


1994 - 2007

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Zertifikat für das Qualitätsmanagement-System


J+G is the first refractory engineering company with certified quality management system.

Experience and know-how helped to get the order to build the biggest circulating fluidized bed power plant in Europe in Gardanne/France.

Zementwerk der Heidelberger Zement AG


Within nine work days 436 m³ of refractories were broken out and within 42 days 596 m³ of new refractories installed. For the Heidelberger Zement AG cement company at their plant in Schelklingen the scheduled installation time was shortened by seven days. This proves that J+G cannot only plan big refractory projects but execute them in record time.

Stefan Schuhmacher bei einer Rede


After 50 years of company service and an unusual career Stefan Schuhmacher retires from J+G. He made a major contribution to the development of refractory engineering at J+G. As part of a retirement ceremony at the castle in Schwetzingen he is rewarded the medal of honor of the State of Baden-Wuerttemberg as ordered by Governor Erwin Teufel.

Sales exceed DM 50 million for the first time.

Eisenerzreduktions-Anlage in Trinidad


JuSyS® was filed at the patent office as collective trade name for J+G specific system solutions.

Order received for refractory engineering, supply of refractories and installation of the refractories for an iron ore reduction plant according to the “Circored“ process of Lurgi-Metallurgi on the Caribbean island Trinidad. 180,000 hours of work without an accident, 1,510 m³ refractories, 490 m³ insulation, 17 pieces of machinery, 143 individual components and over 500 m of lined pipes show the magnitude and coordination effort required for this project.

Neuer Leiter der kaufmännischen Abteilung, Wolfram Arnold


Urban Butz deceases. Wolfram Arnold takes over the commercial department.

Sales over DM 60 million for the first time.

Filing of the patent for the “rear-ventilated system“ which revolutionized under the trade name  JuSyS®Air the worldwide market for tile systems in refuse incineration. Corrosion of boiler walls and anchoring systems was no longer an issue. New service life records were achieved at ease. At the moment more than 100 refuse incinerator lines are equipped with JuSyS®Air.

Schutzauskleidung einer Sondermüllverbrennungsanlage in England


First meeting with Karl-Heinz Elling in Klötze to discuss the founding of “RefraServ GmbH“. The contract was notarized on June 6, 2001.

A service life of ten years was the requirement for the construction of the flue gas recuperators in the special refuse incinerator operated by the Cleanaway company in England. The service life of the protective linings at that time was below two years. Today the customers know that, based on J+G expertise, they can rely on service life statements made by J+G. The first J+G lining is still in operation in its anniversary year.

Zertifikat für das Arbeitssicherheits-Management-System


The occupational safety management system of J+G is certified.

A strategic milestone for the special refuse incineration sector. For the first time J+G has a refractory manufacturer produce chrome-corundum bricks according to requirements and recipe given by J+G. The innovative product with superb performance is marketed with the trade name JUBRICK TE600A. In the years to come this product is further enhanced based on J+G know-how.

Leni und Fritz Gräter


Leni Gräter deceases at age 84. Fritz Gräter sen. deceases at age 85.

Neuer Geschäftsführer Markus Horn


Markus Horn becomes executive manager. With Andreas Gräter the fourth generation is active in the family business.

Degussa places an order over €4 million. The steel and refractory engineering was supplied for six reactors to produce hydrocyanic acid out of methane and ammonia. The installation work was done in Antwerp/Belgium.

Scheidender Geschäftsführer Fritz Gräter Junior


At the end of the year Fritz Gräter leaves his position as executive manager of  “Jünger+Gräter GmbH Feuerfestbau“. However, together with Andreas Gräter he remains part of the executive management of the parent company.

J+G receives the order for the construction of three stationary circulating fluidized bed plants for   the disposal of residual materials for Indaver in Antwerp. The plants are lined with the new “light” refractory concept which enables the plant engineers to use 10 % less steel.

Innenauskleidung einer Brennkammer in Witzenhausen


Share capital now in Euro and increased to €3 million.  

Sales over €40 million for the first time.

Development of special, highly abrasion-resistant and thermal shock resistant fireclay and andalusite bricks according to own recipe. These products open the door to the so-called substitute fuel power plants based on a circulating fluidized bed. J+G received three orders for plants in Witzenhausen, Wittenberg and Schwedt. Over 4,000 tons of refractories were installed.

Müllverbrennungsanlage Innenansicht


“Socoré s.à.r.l.“ moves to Mions near Lyon and now operates under the new name “Jünger+Gräter S.A.R.L.“.

New laws and regulations often have a major economic impact on companies. Starting 2005 it was no longer permitted to send untreated household refuse to dump sites. This had a very positive effect for J+G in that we received new construction orders for 26 refuse incinerator lines in one year.


2008 - heute

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Neues Jünger und Gräter Logo mit dem Zusatz " Refractories"


In the logo the word “Feuerfestbau“ is replaced by the word “Refractories“.

Sales of the J+G Group over €50 million for the first time.  New name “Jünger+Gräter GmbH“.

18 gasification reactors were built for “Shell Global Solutions“ in the desert sand in Qatar with over 2,000 tons of refractories. The order value exceeded €5 million. During the boom phase of this project named “Pearl GTL” over 45,000 engineers and workers from all over the world were on site. As one of only few companies J+G got an appreciation award for reliability in the sectors occupational health, environmental protection and safety at the construction site.


Founding of “Jünger+Gräter Schweiz GmbH“ in Gebenstorf/Switzerland.

Unification of the holding companies to “Jünger+Gräter Holding GmbH“.

Expansion of the JuSyS®-refractory systems with installation of these systems in the petrochemical sector in ethylene cracking furnaces (JuSyS®LW Light Weight), in the cement sector in zones stressed by high corrosion in the preheater (JuSyS®ACL Anti Corrosion Lining) and in circulating fluidized beds plant parts subjected to high erosion such as the cyclones (JuSyS®CFB Circulated Fluidized Bed).

Fertiger Erweiterungsbau am Josef-Jünger-Haus


New office space added to the Josef-Jünger-House.

Sales over €65 million for the first time in the J+G Group.

Lining of a methanol reformer in Oman. J+G received the order because we had the most convincing concept of three international “refractory consultants”. Within 12 hours 26 tons of self-flowing refractory castables were poured behind molds made in the workshops of J+G. This is probably the largest refractory lining without joints in the world which was installed by continuous casting.

Mitgesellschafter Andreas Gräter


Founding of “Jünger+Gräter Austria GmbH“ in Vienna/Austria.

Markus Horn and Andreas Gräter become fellow partners of Jünger+Gräter GmbH. Increase of capital to €5 million.

75th anniversary of J+G.

Neues Logistikzentrum in Schwetzingen


Completion of the new logistics center in Schwetzingen. With a capacity of 4,000 pallets and modern inventory management system J+G reacts to increased requirements regarding reaction times, traceability of supplies, quality control of service and maintenance on the industrial furnaces. The construction of the logistics center is the biggest individual investment in the long company history of J+G. Own funds were exclusively used for this investment.

Ersatz eines Wirbelschicht-Zinkrösters


Complete replacement of a circulating fluidized bed zinc roaster by J+G as general contractor within 44 days at Nyrstar in Balen/Belgium. In addition to the refractories, J+G was responsible for breakout of old refractories, teardown of the old furnace, steel construction for the vessels and outer insulation. This order was one of the biggest individual projects ever handled by J+G.

Ersatz eines Wirbelschicht-Zinkrösters


New records were set in 2017 with incoming orders over €70 million for the GmbH (limited liability company) and over €93 million for the entire J+G Group.

Martin Callies is appointed managing shareholder at J+G Schweiz GmbH.

Mrs. Birgit Elling departs RefraServ GmbH as general partner. RefraServ takes over the shares.


Our Philosophy

“People can rely on us to keep our promise!“ *

This statement is the guiding principle, tradition and commitment to which J+G employees have been obliged to for generations. In this sense we have given the best effort day by day for over 80 years for our customers, the company and technological advancement in the refractories sector.  

Closeness to the customer, well trained specialists, expertise, reliability, continuity and sustainability are the columns of our success. This is only possible on a continuous basis with a good relationship with our customers, suppliers and business partners.

Our work focuses on people. Only competent and motivated employees will achieve the objective to keep the customer satisfied over a long period of time.


Our experts perform at the highest quality level to ensure benefits for the customer that they can expect.

We need partners, too. That is why we have close strategic partnerships with the involved partners working at the same level.

Our technological enhancements lead to longer service lives of the refractories and help to better protect our environment.

Our social responsibility is another part of our company philosophy. We support social, humanitarian, sport and cultural organizations and clubs. 

* developed as part of our regular strategy workshop by the J+G management team

Our Quality

The key to success.

The solid and special quality of our consulting and service performances as well as our products and solutions for the customers are the key to the success of the company. This forms the foundation for a long-time successful future.

Our aspiration is to supply our customers continuously with the best products and services.

Quality does not necessarily mean high costs. We view quality as a measurable variable of price and performance. Consequently, our objective is to give the customer the best possible benefit and attractive economic conditions. We always look at our overall performance ranging from making the customized offer to maintenance of the plant for several years to come.

Based on over 80 years of experience, we can develop and offer very specialized customer concepts which fulfill all quality and safety requirements.

In order to externally document our high quality standards we were one of the first German companies in refractory engineering to implement a quality management system based on DIN EN ISO 9001. Of course this is still part of all our business processes.

We do not just rely on simple supplier assessments when it comes to supply and service. We “live” our supplier relationships in a true partnership to boost quality assurance. We are always available for our suppliers with all our expertise benefiting their product development and product enhancement.

The steady expansion of our customer base, positive feedback after customer audits and low amount of complaints prove that we are on the right track when it comes to our quality philosophy to the benefit of customers.


Certificate ISO 9001:2015 J+G Pdf | 2.0 MiB


Health, Safety and Environmental Protection (HSE) are top priority at Jünger+Gräter and a major part or our corporate culture. This results in high objectives:

  • Offer all employees a safe working environment
  • Prevent the occurrence of illness based on work conditions and thereby sustain the performance of the individual employee
  • Limit any negative impact on the environment to the greatest possible extent

In order to achieve these objectives we only employ such employees and service-providers who respect our views and engagement regarding safety, health and environmental protection aspects.

With our certified management systems we secure the sustainability of our structured safety concept. Concerning the daily work procedures in our company this is the most important tool to control the risks in refractory engineering.  

Certificate SCC J+G (Multi-site) Pdf | 1.5 MiB
Certificate ISO 45001 J+G Pdf | 369.2 KiB

J+G Academy

What is the J+G Refractory Academy?
The J+G Refractory Academy identifies, bundles, plans and implements all training activities in the specific fields (refractories, language, management) and secures their effectiveness.

Target Group and Training Topics
The Refractory Academy targets all employees and managers in all J+G companies.

The academy trains these people in management, technology, data processing and safety.

Motivation for the Refractory Academy
All employees in the field of refractory engineering face high requirements regarding know-how and skills. We can only ensure the high quality of our services and performance by providing human resources development for all employees.


WtE Dubai

August 2021

J+G receives the order for the execution of the refractory lining for the world's largest EfW plant under construction in Dubai.

Our long-standing customer Hitachi Zosen INOVA has once again relied on our proven JuSyS Air tile system for its prestigious project in Dubai.

After completion, the plant will generate energy from 1,890,000 tons of waste per year and thus make a major contribution to Dubai's sustainability strategy.

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J+G receives dirst direct order from Japan for the Biomass Yonago project

February 2020

After more than 1.5 years of intensive acquisition, J+G succeeded in convincing our customer Toyo Engineering of the advantages of our innovative JuSyS CFB tile-system compared to a conventional refractory castable lining. As a result, we were awarded the contract for engineering, material supply and supervision. This is an important strategic step in a dynamically developing market for renewable energy.

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5th CFB Workshop 2019

December 2019

Almost 100 international participants accepted Jünger+Gräter's invitation under the motto "Exchange of experience on the subject of stationary and circulating fluidized bed plants". From 20 to 22 November 2019, experts from the industry exchanged views on current issues. Numerous lectures and an impressive demonstration of mechanical concrete demolition on pipe walls without pipe damage by Aqua Demolition Services B.V. made the workshop a complete success.

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Current job/professional training opportunities

Jobs with a Future. Quality with Training.

We look forward to receiving your unsolicited application.


Job opportunity

Refractory and Chimney Builder m/f

Refractory and Chimney builders construct and upgrade industrial furnaces operating at extremely high temperatures. Their work also includes waste gas mains and chimneys. Specific tasks are bricklaying, pouring, ramming or gluing of concrete and refractory castables according to state-of-the-art.

They process and install refractory and heat-resistant materials that are subjected to several stress factors. In building industrial chimneys they build walls out of reinforced concrete and position chimney belts, cowls and lightning protection systems. In both the refractory and chimney sectors the men and women conduct tests, do maintenance and repair work, look for damages and the causes and execute the work needed to ensure that everything is in good order.

Are you interested in a diversified work with a good future? Then please send your qualified and complete application by mail or email.


Start of the job: Now or in consultation
Location: Construction Sites in Germany and the European Union
Working hours: Full time

School education: at least secondary school
Languages: German (business fluent)
Driver’s license: Is required

Please send your complete application (including resume and references etc.) to:

Klaus Wagner
Jünger+Gräter GmbH
Robert-Bosch-Straße 1 • 68723 Schwetzingen
Tel. +49 (0) 6202 944-107 • k.wagner@jg-refractories.com

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Feel free to contact us:

+49 6202 944 0+496202944194

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