• Product information

    Bosch glow plugs: over 90 years of experience

    Start of development of the first Bosch glow plug for heavy oil engines with a 1-pin, mica-insulated plug. This was an open nickel wire coil with 2 turns. The electrical values were 1.7 V and approx. 37 A.

    Start of series production of the Bosch glow plug with mica-insulating material – i.e. even before the diesel truck (1924) or diesel passenger car (1936) came on the market.

    Production of the first 2-pin Bosch glow wire plug. Normal preheating time up to 180 seconds.

    The first single coil glow plug generation with sheathed element instead of glow wire was able to reduce the preheating time to as little as 45 seconds.

    20 years later, the first double-coil glow plug followed, called Rasant® (RSK). This was a breakthrough: preheating time < 15 seconds.

    The Super-Rasant® (S-RSK), with a preheating time of < 8 seconds, came onto the market.

    Duraterm®, the Bosch-patented glow plug, with its fast preheating time and long post-glow time, revolutionized the diesel world:
    • Preheating time ≈ 4 seconds
    • Post-glow time of up to 180 seconds
    Without this invention, diesel engine development would have been much slower.

    Bosch drastically streamlined the glow plug range, but without any loss of vehicle coverage. Wherever possible, the standard glow plugs were replaced with Duraterm®. Owners of earlier vehicle generations benefited from the short Duraterm® preheating time ≈ 4 seconds as well as a 40 % longer service life (without post-glow function).

    While retaining the earlier technical specifications, the Super-Rasant® plugs were adapted to Duraterm® technology.