Heat tests

This test is conducted to quickly obtain data indicating deterioration and is used instead of the vacuum stability test when the effect of polymers on the stability of highly sensitive explosives is to be studied. A 0.6 g explosive mixed with 0.6 g polymer and also explosive and polymer separately are heated for two cycles, each of 48-h period at 100 °C. A 5% loss during the two cycles, each of 48-h period, or an explosion within 100 hours indicates excessive deterioration. 

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Miscellaneous Fastness Tests. The fastness to hot pressiag, ISO 10S-X1 /, test is similar to the fastness to dry heat test except that the time of pressing is 15 s (again at 150, 180, and 210°C), and the test can either be carried out dry when a damp cotton fabric containing its own weight of water is placed on top of the dry test fabric, or wet when the test fabric also contains its own weight of water. 

If it is variable, set the outside air intake quantity to the winter value. Set the desired temperature up to a maximum, leaving the humidity setting alone. It will be appreciated that as the room temperature rises during the heating test the rh tends to fall. However, since the humidity setting remains unaltered the humidifying system will be called upon to operate until at one condition it is working at peak winter rate. Due to the faster characteristic of heaters, the rh will be found to fall but absolute moisture should be found to steadily rise. The duration of the test is normally about 3 h and final conditions should be held for half an hour to prove the moisture source. 

Cyclic heating tests on electrically heated nickel-chromium and nickel-chromium-iron wires in nitrogenshowed that the lives to burn-out were at least as good as those obtained in air. The same was true in ammonia at 1 050°C, but at 1 150°C and above the life was less in ammonia than in air (Table 7.30) indicating, as would be expected, that it is atomic nitrogen which is most effectively absorbed. 

Table 7.30 Results of cyclic heating tests in various atmospheres...

There are different heat tests, some being specific to a product environment. There are those for temperature and also humidity. With certain materials, humidity combined with elevated temperatures has a significant effect on the material s behavior. This effect would not be evident in the conventional heat distortion test (HDT). 

Specific Volume of Gases Formed on Explosion. 723ml/g (NG 712ml) (Ref 46) Stabilization. Chromatographically pure Mannitol Hexanitrate was mixed with varying percentages of 22 stabilizers and the mixts tested for stability in the 100° heat test best results were obtained with a mixt of 96% MHN, 2% Amm oxalate, and 2% dicyandiamide (4.07% wt loss after 48 hours, 5.74% after 96 hours) (Ref 56). The use of ethylene oxide as a stabilizer is reported in Ref 27 Thermal Decomposition. Slow heating causes decompn at 150° with evolution of red fumes (Ref 20, p 249)... 

Heat Tests, Effect of heat at 300° NMe has a half-life of 30 days, at 350° it decomposes slowly, at 350—400° it decomposes slowly and completely, above 400° an autocatalytic decompn sets in resulting in deton however, it may detonate unexpectedly at any temp above 300° (Ref 16)... 

PA. Rifle bullet impact in welded cans gave 4/4 high order detonations. Thermal stability at 135°, acid in 15—30 minutes at 82.2° heat test, 10 minutes at 82.2°. This material and its homologs from other aliphatic nitro compounds and aldehydes have been suggested as substitutes for NG... 

Impact Sensitivity. > 100cm with 2kg weight or less sensitive than TNT Thermal Stability. Unsatisfactory (about 6 minutes in the 82.2° Heat Test)... 

KI test, comparable to NG and in 15—30 minutes in 135° Heat Test no explosion in 300 minutes... 

Stability. In 100° Heat Test loses 2.5% wt in first 48 hours and 1.8% in second 48 hours no expl in 100 hours. In 100° Vacuum Stability Test, evolves 1.9cc of gas per g in 40 hours not considered very satisfactory Volatility. At 60°, loses 24mgs/cm2 in 1 hour... 

Heat Tests. International heat test at 75° resulted in a 0.05% wt loss. It is not appreciably affected by storage after one year at 50° (Refs 14, 19 20). Vacuum stability test at 120° -... 

Expln temp is above 360°. Impact sensy is 50cm using a BM machine. Hygry test at 90% RH showed gain of 0.88%, and at 100% RH a gain of 1.61% was demonstrated. The International Heat Test at 75° showed a 1.1% loss of wt. Stability testing at 135° for 300 mins showed no acidity or expln. Vacuum stability a 5g sample yielded 12cc of gas in 48 hrs (Ref 3)... 

Heat Test. Loss 1st 48 hrs 0,07% loss 2nd 48 hrs 0.00% explosion in 100 hrs none Hygroscopicity. % wt gain at 30°, 90% RH trace Vacuum Stability Test, cc/40 hrs at 90° none 100° none 120° 0.11 Sand Bomb Test (200g). 16.3 g sand Sensitivity to Initiation. Minimum detonating charge, g LA 0.20 Tetryl 0.25 Solubility. g/lOOcc solvent in water at 100° 0.10 NB at 150°, <15. Sol in acet ac, nitric acid, caustic potash v sol in dimethyl form-amide insol in ethyl ale, benz, butyl acetate, CC14 ethyl ether (Ref 6)... 

KI Heat Test 2 minutes Specification minimum 15 minutes... 

KI Heat Test Gelatinizing action on Nitrocellulose Toxicity... 

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