Framing camera

VasU ev (Ref 36) impacted various explosives with steel plates and followed events with a framing camera. PA at 1,59g/cc impacted with a 3-mm thick steel plate at 430m/sec showed only deflagration and no expins. Initially the burning rate was low but reached 600m/sec in about 65 microseconds after impact C. Potential Hazards. The main danger of accidental expln of PA appears to be in fires. There appears to be uncertainty if explns result if PA bums out of contact with metals. On p 494, Urbanski (Ref 35) states ... 

A complete framing camera sequence of the initiation and growth of expln in NG/EGDN mixts is shown in Fig 19 of the report. Figs 20-28 give more detailed photographs of the same phenomenon (pp 7-13 of Ref 12b). They are not reproduced here... 

TNT , 50% fine 50% coarse (-6+8 mesh) of density 1.12 and chge diam 4.8 mm, initiated with "Knotted Primacord" had initial vel of 2070 at the distance from initiator of 5.0 cm, then at the distance of 7.4 cm the vel was 3190 and after this a stable regime was established with vel 5150m/sec. The three-regime transient phenomena are also illustrated by framing-camera results for cast TNT shown in Fig 3.13, p 55. Here... 

Observations of initiation were conducted at the BurMines using a high-speed framing camera. The procedure was the same as described here in the section "Detonation (and Explosion), Development (Transition) from Burning (Combustion or Deflagration. Drawing of a test vessel used for initiation and growth studies in liquid expls is in Fig 18 of the report... 

R.E. Duff, JScilnstr 26, 256-60(1955) (Preci-. sion measurement of deton and strong shock vel in gases) 57) R.T. Keyes, "Framing Camera Studies of Phenomena Associated with. the Detonation of High.Explosives , Univ of Utah,-... 

Prior to World War 11, Dr. C. N. Hickman of Bell Labs invented the ribbon-frame camera using the inexpensive 122 size (post-... 

Frequently it is as necessary to cut off the illumination as quickly and precisely as it is to turn it on. Internal electro-shuttering, such as accomplished with the Faraday and Kerr cells, can be synchronized with the camera and event exactly as needed (Ref 17). However, as mentioned1 above, cameras such as the Beckman/ Whitley framing camera as well as most continuously writing streak cameras, run the risk of incurring double exposures (Ref 13). 

Ionization in a Detonation Wave. Hay et al (Ref 9) obtained high-speed framing camera pictures and time-resolved spectrograms of the... 

Chaudri et al (Ref 21) claim to have observed an unexpectedly high detonation velocity of about 8km/sec for single crystals of cr-lead azide of 2 x 2mm cross-section. They used a framing camera at a framing rate of 5 x 106 sec 1 for their measurements. Frequently it is difficult to obtain reliable quantitative data by this method... 

Deton velocities were confirmed using high vel framing cameras. The author concludes that the w content conditions of the test prevail in expl mfg plants after expl washing and filtering. He recommends that these expls be assigned a safety classification of Class 9 at this step in their processing... 

The sensitivity of dextrinated and PVA lead azides to shocks of short duration (about 0.1 psec) was determined by impacting samples with a thin plate, observing the impact with a fast-framing camera, and measuring the transmitted stresses with a quartz gauge [46] (Figure 26). 

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