Drum friction test

The standard series DIN 22 109 is devoted to canvas-lined conveyor belts. Test methods prescribed by DIN 22 109 Teil 6, 1984 (E) are quite similar to the drum friction test and to the propane burner tests of BS 3289 1982. 

B. Matecki and J. Wachowicz in Problems Involved in the Application of the Drum Friction Test for Evaluating Fire Resistant Rubber Conveyor Belts in the Mining Industry, Przegl d Gorniczy, Poland, 1992, 10, 10. 

A major area of negotiation in the development of the specification concerned the Drum Friction Test. This is a test which simulates a stalled belt. The NCB test in force had evolved after the Creswell Colliery disaster of 1953. A stalled rubber belt had remained in contact with its drive drum which continued to run for several hours. The frictional heat caused a fire which resulted in several fatalities. The drum friction test to emerge afterwards stipulated that the belt shall break, in addition to drum temperature and belt flow limitations. In effect this meant a textile-reinforced PVC belt in which the frictional heat melts the PVC and then melt-breaks the synthetic-fibre fabric as it makes contact with the drum. Such a belt meets the drum friction requirements and the NCB used this type of belt for many years. The steel-cable reinforced rubber-belt needed for the single-belt installation, first at Cadley Hill, and then at... 

To meet this specification a special cover compound was designed at BTR. It is a carbon-black filled polychloroprene rubber, which forms a smooth, carbonized, glazed surface during the drum friction test, and usually gives a maximum temperature of 200-250 C. 

The Drum Friction Test is a type-approval test, and not a routine quality-control test. Such a test is used in the establishment of a satisfactory manufacturing specification. 

Negri et al. [301] have applied TG-DTA to the characterisation of different types of carbon-black in NR vulcanisates. The method allowed determination of the overall CB content, but where combinations of different blacks were present it was not possible to determine the proportion of each type. TG-DTA has also been used to correlate TGA in airflow and N2 gas flow and some other micro-scale flammability tests i.e., oxygen index, hot-plate ignition and drum friction tests) on covers of different flame-resistant and non flame-resistant rubber conveyer belts [302]. The minimum temperatures at which rapid weight loss of each sample began to appear were determined and compared with the results from the micro-scale flammability tests. 

In another elongational rheometer (264), the specimen is suspended on the end of a flexible tape, which is wound onto a wheel turned by a servo-controlled torque motor. This design is the basis for the Gottfert Rheostrain instrument. One device for melts and solids is an add-on fixture for rotational rheometers. The SER testing platform (267) incorporates dual wind-up drums and can be used for tensile, tear, peel, and friction testing as well as for elongational viscosity measurements. 

In order to define the extent of emissions from automotive brakes and clutches, a study was carried out in which specially designed wear debris collectors were built for the drum brake, the disk brake, and the clutch of a popular U.S. vehicle (1). The vehicle was driven through various test cycles to determine the extent and type of brake emissions generated under all driving conditions. Typical original equipment and aftermarket friction materials were evaluated. Brake relines were made to simulate consumer practices. The wear debris was analyzed by a combination of optical and electron microscopy to ascertain the asbestos content and its particle size distribution. It was found that more than 99.7% of the asbestos was converted to a nonfibrous form and... 

A further attempt to better simulate the wear conditions for tyres resulted in the FKK wear tester66. An abrasive belt is run over two drums and it is claimed that the same friction conditions as service are achieved. The test... 

Chase machine Friction sample ( - 25.4 mm square pad) rubbing against the inner diameter of a rotating drum Used to conduct SAE J661 tests for friction edge code determination... 

Table 1 provides the basic data used to describe the materials, ropes, and machine characteristics in the model. The values in Table 1 are based on existing steel ropes and an equivalent synthetic rope as well as the existing hoists at LKAB. Future bend-over-sheave testing of ropes will determine whether or not an increased diameter is feasible. Maximum friction coefficient used in all cases is the maximum value allowed by the Swedish standards for mining hoists (BRAGS). While the friction values can be considered high, it is assumed that apphcation specific drum hning materials can be developed to be used with synthetic ropes. 

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