ISO 7578 pdf download.Road vehicles — Sheath-type glow-plugs — General requirements and test methods
1 Scope
This International Standard specifies general requirements and bench test methods for sheath-type glow-plugs. It is applicable to those sheath-type glow-plugs conforming with ISO 6550-1 , ISO 6550-2 and ISO 6550-3, used in diesel (compression ignition) engines of vehicles equipped with 1 2 V or 24 V nominal voltage supply systems.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 6550-1 , Road vehicles — Sheath-type glow-plugs with conical seating and their cylinder head housing — Part1: M14 x 1,25glow-plugs ISO 6550-2, Road vehicles — Sheath-type glow-plugs with conical seating and their cylinder head housing — Part2: M12 x 1,25glow-plugs ISO 6550-3, Road vehicles — Sheath-type glow-plugs with conical seating and their cylinder head housing — Part3: M10 glow-plugs IEC 60068-2-6, Environmentaltesting — Part 2: Tests — TestFc: Vibration (sinusoidal)
3 Test methods and requirements
3.1 General The tests shall be carried out at an ambient temperature of (23 ± 5) ° C, unless otherwise specified. 3.2 Gas tightness 3.2.1 Test Mount the sample on a test device with the tightening torque specified in the relevant part of ISO 6550. Subject the sample to a pressure of 4 MPa [40 bar 1 ) ] above ambient air pressure on the sheath end for a duration of 1 5 s. Use air, nitrogen, carbon dioxide or any other detection gas.NOTE At the time of publication, the pressure value of 4 MPa (40 bar) was under study, the intention being to increase it. 3.2.2 Requirements The measured total leakage shall not exceed 2 cm 3 /min. If neither air nor nitrogen is used, the leakage rate shall be converted to that of air using the specific volume of the detection gas. 3.3 Thermal characteristic 3.3.1 Test sample preparation Before the test, pre-heat the sample to oxidation at the nominal voltage of the glow-plug and then allow it to cool to ambient temperature. The time for oxidation shall be either as agreed between the glow-plug manufacturer and the engine manufacturer, or 3 min. 3.3.2 Test Carry out the test using a test installation in accordance with Figure 1 (see Table 1 ), equipped with a cooling device by which the temperature can be maintained below 30 °C, measured at the seating of the glow-plug housing. If the thermal behaviour is measured according to a specific application, this shall be by agreement between the glow-plug manufacturer and the engine manufacturer. Carry out the test at the nominal voltage of the glow-plug. A tolerance of ± 0,1 V is permitted. Temperature measurements shall be made without direct contact.
3.3.3 Requirements
3.3.3.1 Normal sheath-type glow-plugs The hottest point of a normal glow-plug shall be found within the measuring zone, C 3 , shown in Figure 1 and given in Table 1 as 8 mm. At this hottest point, the sheath shall have reached a temperature of 850 °C within 20 s and 1 000 °C within 60 s. 3.3.3.2 Fast warm-up sheath-type glow-plugs The hottest point of a fast warm-up glow-plug shall be found within the measuring zone, C 3 , shown in Figure 1 and given in Table 1 as 5 mm. At this hottest point, the sheath shall have reached a temperature of 850 °C within 1 0 s. During the following 50 s the temperature shall not drop below 800 °C. 3.3.3.3 Systems with electronic control For systems with electronic control, the glow-plug manufacturer and the engine manufacturer shall agree on system performance.