1、January 2010DEUTSCHE NORM English price group 12No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 21.200!$V“1565195www.d
2、in.deDDIN ISO 14635-2Gears FZG test procedures Part 2: FZG step load test A10/16, 6R/120 for relative scuffingload-carrying capacity of high EP oils (ISO 14635-2:2004)English version of DIN ISO 14635-2:2010-01Zahnrder FZG-Prfverfahren Teil 2: FZG-Prfverfahren A10/16, 6R/120 zur Bestimmung der relati
3、venFresstragfhigkeit von hoch EP-legierten Schmierlen (ISO 14635-2:2004)Englische Fassung DIN ISO 14635-2:2010-01www.beuth.deDocument comprises pages24DIN ISO 14635-2:2010-01 Contents Page National Foreword . 3 Introduction 5 1 Scope 6 2 Normative references . 6 3 Terms and definitions. 7 4 Failure
4、criteria . 7 5 Brief description of method . 9 5.1 General principle. 9 5.2 Precision 9 6 Test materials 9 6.1 Test gears 9 6.2 Cleaning fluid 9 7 Apparatus. 9 7.1 FZG spur-gear test rig 9 7.2 Heating device. 11 7.3 Revolution counter . 11 7.4 Balance. 11 8 Preparation of apparatus 13 9 Test procedu
5、re 13 10 Reporting of results 15 Annex A (informative) FZG A10-type gear tooth face changes (flank damages). 16 Annex B (informative) Typical FZG test report sheet . 18 Annex C (informative) Checklist for maintenance of FZG gear test rig 19 Bibliography . 24 2National Annex NA (informative) Bibliogr
6、aphy . . 4 DIN ISO 14635-2:2010-01 National foreword This standard has been prepared by Technical Committee ISO/TC 60 “Gears” (Secretariat: ANSI, USA), Subcommittee SC 2 “Gear capacity calculation”. The responsible German body involved in its preparation was the Normenausschuss Maschinenbau (Mechani
7、cal Engineering Standards Committee), Working Committee NAM 234-19 Zahnradschmierung und Schmierstoffe of Section Antriebstechnik. The text of ISO 14635-2:2004 has been adopted without any modifications. Attention is drawn to the possibility that some of the elements of this document may be the subj
8、ect of patent rights. DIN shall not be held responsible for identifying any or all such patent rights. DIN ISO 14635 consists of the following parts, under the general title Gears FZG test procedures: Part 1: FZG test method A/8,3/90 for relative scuffing load-carrying capacity of oils Part 2: FZG s
9、tep load test A10/16, 6R/120 for relative scuffing load-carrying capacity of high EP oils Part 3: FZG test method A/2, 8/50 for relative scuffing load-carrying capacity and wear characteristics of semifluid gear greases The International Standards referred to in clause 2 of this document have been p
10、ublished as the corresponding DIN EN ISO or DIN ISO Standards with the same number, except for those below, which correspond as follows: ISO 1122-1 DIN 868, DIN 3998-1 bis DIN 3998-4 ISO 1328-1 DIN 3961, DIN 3962-1, DIN 3962-2, DIN 3963 ISO 4964 (withdrawn 2005-07) there is no national standard avai
11、lable ISO/TR 10064-4 DIN 3961 ISO 10825 DIN 3979 ISO 12925-1 there is no national standard available ISO/TR 13989-1 DIN 3990-4 ISO/TR 13989-2 DIN 3990-4 ASTM D 235 there is no national standard available For the European publications referred to in the Bibliography, there are no national documents a
12、vailable. 3DIN ISO 14635-2:2010-01 National Annex NA (informative) Bibliography DIN 868, General definitions and specification factors for gears, gear pairs and gear trains DIN 3961, Tolerances for cylindrical gear teeth Bases DIN 3962-1, Tolerances for cylindrical gear teeth Tolerances for deviatio
13、ns of individual parameters DIN 3962-2, Tolerances for cylindrical gear teeth Tolerances for tooth trace deviations DIN 3963, Tolerances for cylindrical gear teeth Tolerances for working deviations DIN 3979, Tooth Damage on Gear Trains Designation, characteristics, causes DIN 3990-4, Tragfhigkeitsbe
14、rechnung von Stirnrdern Berechnung der Fresstragfhigkeit DIN 3998-1, Denominations on gears and gear pairs General definitions DIN 3998-2, Denominations on gears and gear pairs Cylindrical gears and gear pairs DIN 3998-3, Denominations on gears and gear pairs Bevel and hypoid gears and gear pairs DI
15、N 3998-4, Denominations on gears and gear pairs Worm gear pairs 4Introduction The types of gear failures which may be influenced by the lubricant in use are scuffing, low-speed wear and the gear-surface fatigue phenomena known as micropitting and pitting. In the gear design process, these gear damag
16、es are taken into consideration by the use of specific lubricant and service-related characteristic values. For an accurate, field-related selection of these values, adequate lubricant test procedures are required. The FZG test procedures specified in this and the other parts of ISO 14635 can be reg
17、arded as tools for the determination of the lubricant-related characteristic values to be introduced into the load-carrying capacity calculation of gears. FZG test method A/8,3/90 for the relative scuffing load-carrying capacity of oils described in ISO 14635-1 is typical for the majority of applica
18、tions in industrial and marine gears. This part of ISO 14635 is related to the relative scuffing load-carrying capacity of oils of very high EP properties, as used for the lubrication of automotive driveline components. Other FZG test procedures for the determination of low-speed wear, micropitting
19、and pitting load-carrying capacity of gears are already in a late state of development. They may be added later to ISO 14635 as further parts. DIN ISO 14635-2:2010-01 5Gears FZG test procedures Part 2: FZG step load test A10/16, 6R/120 for relative scuffing load-carrying capacity of high EP oils 1 S
20、cope This part of ISO 14635 specifies a test method based on an FZG1)four-square test machine to determine the relative load-carrying capacity of high EP oils defined by the gear surface damage known as scuffing. This test method is useful for evaluating the scuffing load capacity potential of oils
21、typically used with highly stressed cylindrical gearing found in many vehicle and stationary applications. It is not suitable for establishing the scuffing load capacity potential of oils used in highly loaded hypoid bevel gearing applications, for which purpose other methods are available in the in
22、dustry. NOTE This method is technically equivalent to CEC L-84-02. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced docu
23、ment (including any amendments) applies. ISO 1328-1, Cylindrical gears ISO system of accuracy Part 1: Definitions and allowable values of deviations relevant to corresponding flanks of gear teeth ISO 4287, Geometrical Product Specifications (GPS) Surface texture: Profile method Terms, definitions an
24、d surface texture parameters ISO 4964, Steel Hardness conversions ISO 5725-2, Accuracy (trueness and precision) of measurement methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method ISO 14635-1, Gears FZG test procedures P
25、art 1: FZG test method A/8,3/90 for relative scuffing load-carrying capacity of oils ASTM D 235, Standard Specification for Mineral Spirits (Petroleum Spirits) (Hydrocarbon Dry Cleaning Solvent) 1)FZG = Forschungsstelle fr Zahnrder und Getriebebau, Technische Universitt Mnchen (Gear Research Centre,
26、 Technical University, Munich), Boltzmannstrae 15, D-85748 Garching, Germany. DIN ISO 14635-2:2010-01 63 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 scuffing particularly severe form of gear tooth surface damage in which seizure or welding
27、together of areas of tooth surface occur, owing to the absence or breakdown of a lubricant film between the contacting tooth flanks of mating gears, typically caused by high temperature and high pressure NOTE Scuffing is most likely when surface velocities are high. It can also occur at relatively l
28、ow sliding velocities when tooth surface pressures are high enough either generally or, because of uneven surface geometry and loading, in discrete areas. 3.2 scuffing load-carrying capacity of a lubricant maximum load which can be sustained under a defined set of conditions NOTE It is the minimum l
29、oad stage at which the failure criteria given in Clause 4 is reached. See Table 1. 3.3 FZG test condition A10/16,6R/120 test condition where A10 is the particular tooth form of the test gears, according to Tables 2 and 3, 16,6 is the speed at the pitch circle, in metres per second, “R” indicates the
30、 reverse direction of rotation (wheel drives pinion) and 120 is the initial oil temperature in degrees Celsius, from load stage 4 onward in the oil sump 3.4 failure load stage load stage reached when the sum of the damage to the 16 pinion teeth exceeds 100 mm2in total area damaged NOTE See Clause 4
31、and Table 1. 3.5 high EP oils lubricants containing chemical additives appropriate for improving their scuffing load capacity NOTE 1 EP = extreme pressure. NOTE 2 These oils typically exceed the limits of the FZG test according to ISO 14635-1. 4 Failure criteria Risk of scuffing damage varies with t
32、he properties of gear materials, the lubricant used, the surface roughness of tooth flanks, the sliding velocities and the load. Consequences of scuffing include a tendency to high levels of dynamic loading owing to an increase of vibrations, which usually leads to further damage by scuffing, pittin
33、g or tooth breakage. Because of the particular gear design and test loads used, an interference area typically results at the tip of the pinion and root of the mating wheel. This area is usually about 1 mm in length (profile direction) on the pinion and across the entire face width. Examples of vari
34、ous levels of distress occurring with this test are shown in Annex A. The effect of the surface distress in these two regions is addressed as follows. a) For the purpose of the visual rating for scuffing, the top 1 mm near the tip of the pinion is not included in the assessment until the damage exte
35、nds below that level. The rated damage region is then expressed as the total area scuffed over all 16 pinion teeth (see Figure 1). The failure load stage is reached when the sum of the damage to the 16 pinion teeth exceeds 100 mm2in total area damaged. DIN ISO 14635-2:2010-01 7b) For a valid test, t
36、he wheel shall be visually checked for signs of excessive wear after each pass load stage, as this could alter the results of the test. If there is evidence of wear in the dedendum of the wheel, then the gear shall be weighed to the nearest milligram (0,001 g) see Annex A, d). The test may be consid
37、ered valid only if the loss in mass of the wheel is u 20 mg: if the loss in mass of the wheel exceeds 20 mg, the test shall not be considered valid. See Table 1. Table 1 Test criteria Pinion failure area Amm2Wheel wear m mg Result u 100 u 20 PASS u 100 20 INVALID a 100 Not required FAIL aNo statemen
38、t on the scuffing load is possible. Area in square millimetres Key 1 exclusion zone (1 mm) Figure 1 Schematic of distress rating for pinion DIN ISO 14635-2:2010-01 85 Brief description of method 5.1 General principle A set of test gears as defined in Tables 2 and 3 is run with the test lubricant at
39、constant speed for a fixed number of revolutions using dip-lubrication mode. Loading of the gear teeth is increased in steps outlined in Table 4. Beginning with load stage 4, the initial oil temperature is controlled between 117 C and 123 C. During the test run of each load stage, the oil temperatur
40、e is allowed to rise freely. After load stage 5, the pinion tooth flanks are inspected for surface damage at the end of each load stage and any changes in appearance are noted. A test is considered complete when either the failure criteria have been met or when load stage 10 has been completed witho
41、ut having been met the failure criteria having been met. It is the responsibility of the operator to ensure that all local legislative and statutory requirements are met. NOTE It has been assumed by the compilers of this test method that anyone using the method will either be fully trained and famil
42、iar with all normal engineering and laboratory practice, or will be under the direct supervision of such a person. WARNING When the rig is running, there are long loaded shafts and highly stressed test gears turning at high speed and precaution shall be taken to protect personnel. Protection from no
43、ise is also highly recommended. 5.2 Precision The precision of the method has been evaluated according to ISO 5725-2 with two reference oils. The failure load stage of these oils covered the range 5 to 10 inclusive for the step load test. Values of repeatability (r) and reproducibility (R), as defin
44、ed in ISO 5725-2, for this test procedures are r = 1 load stage, R = 2 load stages. 6 Test materials 6.1 Test gears A pair of type “A10” test gears with a specification according to Tables 2 and 3 shall be used for testing. Each pair of test gears may be used twice for testing, utilizing both tooth
45、flanks as load-carrying flanks. 6.2 Cleaning fluid Petroleum spirit conforming to ASTM D 235. 7 Apparatus 7.1 FZG spur-gear test rig 7.1.1 The FZG spur-gear test machine utilizes a recirculating power loop principle, also known as a four-square configuration, to provide a fixed torque (load) to a pa
46、ir of precision test gears. A schematic view of the test rig is shown in Figures 2 and 3. The slave gearbox and the test gearbox are connected through two torsional shafts. Shaft 1 contains a load coupling used to apply the torque through the use of known weights, defined in Table 4, hung on the loa
47、ding arm. DIN ISO 14635-2:2010-01 97.1.2 The test gearbox contains heating elements to maintain and control the minimum temperature of the oil. A temperature sensor located in the side of the test gearbox is used to control the heating system as required by the test operating conditions. 7.1.3 The t
48、est machine is powered by an electric motor of minimum 7,4 kW at a speed of approximately 2 900 r/min. The direction of drive is reversed (anticlockwise when looking on the motor shaft), i.e. wheel drives pinion, as shown in Figure 3. This is the opposite direction of rotation to that of ISO 14635-1
49、. Table 2 Details of FZG test gears type A10 Dimension Symbol Numerical value Unit Shaft centre distance a 91,5 mm Effective face width pinion b110 mm wheel b220 mm Working pitch diameter pinion dw173,2 mm wheel dw2109,8 mm Tip diameter pinion da188,77 mm wheel da2112,5 mm Module m 4,5 mm Number of teeth pinion z116 wheel z224 Profile shift coefficient pinion x10,853 2 wheel x2 0,50 Pressure angle 20 Degrees Working pressure angle w22,5 Degrees Pitch diameter circumferential speed vw16,6 m/s Addendum
