Blade Strips & Saw Bands
Blade Strips & Saw Bands Our solutions for the hardening and tempering

of razor blades, scalpel blades, carpet knife blades or other metallic blade strips

Continuous hardening and tempering

of blade strips

You want to harden and temper razor blades, scalpel blades, carpet knife blades or other metallic blade strips? We supply turnkey furnace plants for continuous hardening and tempering of blade strips.

With our experience of more than 120 years of industrial furnace construction and more than 160 realized units worldwide, we are the market leader for furnace plants for hardening and tempering blade strip material.

You want to harden and temper special strips, e.g. punched strips, shaver foils or other thin metal strips?

We will find a solution for you! Please contact us.

Process

The continuous process of hardening and tempering stainless steel blade strips

The hardening and tempering of blade strips consists of hardening and subsequent one-time tempering.
The crystal structure of the blade strip is transformed.

In the following, this will be explained briefly and in a very simplified way using the example of martensitic stainless steel.

  • Hardening
    Heating and soaking for austenitizing the blade strip at approx. 1,100°C in the hardening furnace. Conversion of ferrite into austenite; contained carbides are partially dissolved, thereby increasing the content of carbon and chromium in the matrix. Subsequent quenching to room temperature in the quench unit. Conversion of most of the austenite into martensite.
  • Deep-freezing
    of the blade strip in deep-freezing unit to approx. -80°C. Further, permanent transformation of austenite into martensite. Depending on the freezing temperature, approx. 15% retained austenite remains in the microstructure.
  • Tempering
    at approx. 200 °C without soaking time in the tempering furnace. Reduction of brittleness and increase of toughness; achievement of additional hardness. Subsequent cooling to room temperature in the cooling unit.
Plant engineering

Our furnaces for continuous hardening and tempering of blade strips are of modular design and designed for continuous operation. Through the sensible selection of standardised plant components, we configure the plant according to your requirements.

We will be pleased to consider your special requirements beyond our standards.

  • 1 A Abwickler

    Flexible design

    • for flat coils
    • for 1 to 8 strips
    • single or double coilers
    • up to 100 kg coil weight
    • up to 1,200 mm coil diameter
    • 5 to 30 mm strip width
    • traverse winder available
  • 1 B Bandreinigung

    Effective and indispensable
    for thorough removal of grease and punching residues from the blade strip

    • for up to 8 strips
    • cleaning - rinsing - drying
    • fluid tanks for quick change
    • temperature controlled liquids
    • completely made of stainless steel
  • 1 C Bandabzug Schlaufe

    Compact and robust

    for pulling-off the strips from the unwinder

    • for up to 8 strips
    • different types of drives available
    • standardised design
    • loop control for constant band speed in the furnaces
  • With excellent insulation

    • 1 to 4 muffles
    • nominal temperature 1,150 °C
    • heated electrically
    • heated length approx. 7.4 m
    • muffle atmosphere: flammable gases
    • standardized parts
    • excellent thermal insulation
    • sophisticated security concept
  • For wrinkle-free blade strips

    for quenching the blade strips behind the hardening furnace

    • water-cooled
    • indirect cooling
    • protective gas atmosphere for spotless blades
    • modular design
    • standardised unit
  • Low temperature for best quality 
    for minimizing retained austenite in the metal structure after hardening

    • two types available: cooling with liquid nitrogen or compressor cooling
    • nominal temperature depending on Type
      -140 °C or -80 °C
    • indirect cooling
  • For tough and hard blades

    • 1 to 4 muffles
    • 2 versions available
    • heated length approx. 1.2 m or 4.5 m
    • nominal temperature 400 °C or 350 °C
    • heated electrically
    • muffle atmosphere: flammable or non-flammable gases
    • excellent thermal insulation
  • Cool blades for safe handling
    Cooling unit behind the tempering furnace 

    • water-cooled
    • indirect cooling
    • protective gas atmosphere for spotless blades
    • modular design
    • standardised parts
  • 1 I Banddurchzug

    Compact and robust
    for pulling the bands through the furnace

    • for up to 8 strips
    • different types of drives available
    • standardised design
  • 1 J Aufwickler

    Flexible design

    • for flat coils
    • for 1 to 8 strips
    • single or double coilers
    • up to 100 kg coil weight
    • up to 1,200 mm coil diameter
    • 5 to 30 mm Band width
    • traverse winder available
  • Clearly arranged instruments

    to supply the furnace system with the required media

    • process gas
    • protective gas
    • cooling water
  • For operation and control of the furnace system

    • Siemens touch panel
    • storage of measurements, set points and error prompts
    • different password protected user levels
    • monitoring of plant safety
    • Remote Control
    • energy supply for the furnace plant
Main technical data (using the example of a hardening and tempering plant for 4 blade strips)

Plant dimensions (without control cabinet)approx. 25.8 x 1.8 x 2.5 m (L x W x H)
Typical throughputapprox. 91,500 blades per hour (razor blade for safety razor)
Blade strip dimensionsup to approx. 30 x 0.5 mm (width x thickness)
Our services

Same blade – different furnace system

Just because every customer has special requirements

Together with you, we will work out the optimal solution for your request.

  • definition of the scope of supply
  • design of the system based on your specifications
  • configuration of the system from standardised components, customer-specific adaptations
  • presentation of the plant concept
  • preparation of the offer
  • design, production and testing of the system in our factory
  • shipping, assembly, commissioning and acceptance of the plant at your location - around the globe
  • preparation of the plant documentation and the EU declaration of conformity
  • production support
  • services: plant maintenance, spare parts, repairs, measurements
  • network to adjacent processes

We are looking forward to your request, contact us today!

3 14 Leistungen Produktinformationsblatt 630x695
References

Selected references

Satisfied customers - the best proof of successful cooperation

„We want to express our satisfaction with the results of the project, and we sincerely hope that this interaction between our companies was not the last.“
Mr. Hatem Allam, Operation Director at Silver Edge Tech
Furnace plant for the hardening and tempering of razor blade strips

Dates & Facts

  • customer: Silver Edge Technology, Egypt
  • product: blade strips for wet shavers
  • plant: coil-to-coil furnace plant for continuous hardening and tempering of razor blade strips
  • year of construction: 2016
  • scope of supply: engineering, design, construction, shipping, installation and commissioning at the customer, training of operators, after sales services
Furnace plant for the hardening and tempering of razor blade strips

Dates & Facts

  • customer: Feintechnik GmbH Eisfeld
  • product: blade strip for system razors
  • plant: coil-to-coil furnace plant for continuous hardening and tempering of razor blade strips
  • year of construction: 2014/2015
  • scope of supply: plant design, engineering, construction of the furnace plant, shipping, installation at the customer's site, commissioning, operator training, after-sales
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More than 120 years experience in industrial furnace construction

Martin Wiese Key Account Manager +49 551 820 830 - 710 hardening@onejoon.de
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