Free fall test

Experimental results from thermobalance or free-fall tests conducted at IGT indicate that the assumption of a constant volatile carbon fraction is valid for coal heat-up rates as high as 200°F/sec. However, other studies conducted with extremely rapid heat-up rates (104 to 107oF/sec)... 

Impact Resistance. Tests for impact resistance of porcelain enamels include falling weight tests such as a free-falling ball or a pendulum... 

ISO 7765-2, Plastics film and sheeting - Determination of impact resistance by the free-falling dart method - Part 2 Instrumented puncture test, 1994. 

Free Fall Drop. The packages with fuzes shall be dropped free fall 36 inches onto a rigid horizontal surface 6 times, 1 drop on each of 4 diagonally opposed corners, plus one flat drop on bottom and one flat drop on one end. If the container is of the drum type, the top and bottom are quartered and the above test is applied to each of the quartered sections. Photographic view of drop apparatus is given in Fig 225, p 381 of Ref 9... 

X) Velocity Impact Slingshot Test. The purpose of this test is to determine the operating characteristics of fuzes at impact velocities up to ca 300 fps. The test fuze is propelled from a tube downward and is guided to a point ca 3 ft above the target after which it free falls and strikes the target. The velocity is electronically recorded. Only detonators and leads are loaded in the fuze (p IIB-30 of Ref 39)... 

The first bombs developed by the US Navy, CBU-55, were used in Vietnam, and tests to perfect an advanced version of the weapons system have continued. The CBU-55B air-to-surface free-fall cluster bombs were developed for helicopter.and siow-speed fixed-wing aircraft delivery to clear helicopter landing zones of mines booby traps. This FAE bomb was designed to disperse a mixt of vaporized fuel (ethylene oxide, propylene oxide, m e thy lacetylene/propa diene/pro pane and others) in a cloud 50 ft in dram and approx 8 ft thick. It has three 100-lb individual canisters 13.6 inches in diam by 21 inches long, each containing ca 72 lbs of fuel. The canisters separate from the dispenser after... 

Typical performance data are summarized in Table 9.13. In practice air velocities are 10-30 m/scc. The minimum upward velocity should be 2.5-3 m/sec greater than the free fall velocity of the largest particles. Particles in the range of 1-2 mm correspond to an air velocity of 25 m/sec. Since agglomerates may exist under drying conditions, the safest design is that based on pilot plant tests or prior experience. 

Self-Test 6.1A Calculate the work needed for a person of mass 65 kg to go between the two floors of a house, a difference in height of 3.5 m. The difference in potential energy of the person will be mgh, where m is the mass, g is the acceleration of free fall (9.81 m-s 2), and h is the height climbed. 

Method A is a free-fall package-drop test. Method B is a shock... 

The usual method for obtaining samples at significant depths below the surface is to push or drive a pipe or tube into undisturbed soil at the bottom of a drill hole. Of course, this process disturbs the soil, particularly when the pipe is heavy walled. Many different kinds and sizes of samplers are used, and the most common is shown in Figure 1.1. This sampler is commonly called a split spoon. When used with the dimensions shown, and hammered into the soil by a free falling, 140 pound weight, dropping 30 inches, this is the Standard Penetration Test (see ASTM Standard D.1586,... 

Preparation of the Test Samples. Hot mixture is placed in cylindrical molds, having a diameter of 101.6 mm and is compacted by a 4.536 kg hammer descending in free fall from a height of 457 mm onto a metal base which has the same diameter as the mold and is placed on top of the mixture. The Marshall compacting process corresponds to 50 blows on each face. It can be complemented by compacting at 25, 75, and 100 blows/face. The mold must be placed on a wooden pedestal, and the 50 blows should be applied within about 55 sec. 

Typical results of the hydrogasification tests are shown in Tables I, II, and III. Reported coal residence times are based on measured bulk densities of the reactor residues and the coal bed volume. Time in free fall was negligible compared with that in the bed. Feed gas residence... 

ISO 7765-2 1994. Plastics Film and Sheeting - Determination of Impact Resistance by the Free-Falling Dart Method - Part 2 Instrumented Puncture Test. 

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