Harper International

Harper International works in a part of advanced manufacturing that is rarely visible but often decisive: the thermal treatment that transforms raw materials into products with controlled properties. The company designs furnaces, heating systems, and technical services for projects ranging from early research to production lines. Each solution is tailored to the material, process atmosphere, and scale required; it is not limited to off-the-shelf equipment.

Its portfolio includes rotary, pusher-tunnel, vertical-conveyor, belt-conveyor, and batch furnaces, along with carbon-fiber solutions and heating technologies. Harper presents these families as engineering platforms that can be configured around a process. A customer may begin with laboratory-scale trials and move toward an integrated production system, provided the thermal design and equipment integration meet the material’s specific goals.

The company organizes its applications around battery materials, carbon fiber, carbon and graphene, nuclear materials, powder metals, and technical ceramics. It also develops high-temperature processes and systems that operate in atmospheres other than ambient air. That range explains why projects begin with technical consultation: before defining equipment, the team needs to understand the material being processed and the result the production line must achieve.

The company’s history traces back to John L. Harper and his electric kiln and furnace developments in the early 1900s. In the 1940s, Harper and his colleagues developed a furnace for processing nuclear fuel and commercial graphite-element equipment capable of operating at very high temperatures with controlled atmospheres. Harper International was formed in 1989 to acquire patents and technical know-how from John Harper’s company; in 2011, it became employee-owned through an Employee Stock Ownership Plan.

The work does not end when a furnace is delivered. Harper also provides technical services, system integration, and support for moving from concept and development to commercial-scale operation.

A company announcement from December 2025 describes the commissioning of a scientific line for producing carbon fiber from bitumen. It offers a concrete example of the process challenges Harper addresses: engineering an installation around a specific feedstock and application.

Harper lists its corporate headquarters in Buffalo, New York. The company serves international customers and directs sales inquiries outside the United States to its sales team or regional representatives. Given the scale of its projects, the profile is most relevant to manufacturers, research centers, and engineering teams developing or expanding thermal processes for advanced materials. The Buffalo address is a corporate office, not a public-facing location.