Burns. Mark

MPX functionality is arranged into three modules, the first of which is the Setup Xpert, a module that allows users to perform a variety of injection-velocity- and pressure-phase-related setup routines to fix certain defects, such as short shots, flash, burn marks, sink marks, etc. The objective of Setup Xpert is to achieve one good molded part with no defects. The basic process is that a user molds a part, then provides feedback to the MPX system regarding molded part quality. The MPX system then processes this feedback along with data being collected from the machine and (if necessary) determines a process change that will improve the result. 

Figure 1. Photograph of the Shroud showing examples of the various types of marks and images. Key A, body-only image B, blood image C, burn mark D, scorch mark E, water-stain mark F, clear area G, patches and H, Holland cloth. (Reproduced with permission. Copyright 1978, Vernon Miller.)...

Hung, Shang-Chen Wong, Chi-Huey, Tetrahedron Lett., 37 (28), 4903-4906(1996). Parry, Ronald J. Burns, Mark R. Jiralerspong, Sao Alemany, Lawrence, Tetrahedron, 53(21), 7077- 7088 (1997). 

Manquat relates the following Hayem tried phenic acid as a counterirritant. A brush is dipped in a solution of 9 parts crystallized phenic acid [phenol] to 1 part 90% alcohol and is painted on evenly and without letting the solution run. After these applications, the skin often becomes pigmented and retains the burn marks indefinitely. ... 

A low shear heat screw is recommended, with L/D = 18 to 22 and a compression ratio from 2.0 to 2.6. The screw should be protected against corrosion and wear, by either plating or nitrating. If any scratch is observed on the surface of the barrel, screw, or nozzle, it must be repaired immediately, otherwise owing to resin retention, it may cause burn marks or black spots on the moldings. The resin temperature may be checked with a few air shots. Due to thermal degradation, temperatures above 210°C may cause burn marks, black spots or mold-rust. 

Brittleness Burn Marks Discoloration Flashing Sink marks Short shots Splay Sticking roughness long term Remedial action... 

As fast injection speeds are used for PS, burn marks appear on the molding, as a result of inadequate venting, so the position and size of the vents play an important part in... 

Venting is essential with HIPS in order to prevent moldings possessing burn marks or, shading on their surfaces. Typical vent sizes of 0.025 to 0.05mm (0.001 to 0.002in) deep by 4 to 6mm (0.157 to 0.236in) wide are used. 

Burn mark n. Any visual sign of burning or charring at a particular spot on a part. In injection molding with poorly vented molds, burn marks can be caused by severe compression-heating of the air trapped in the mold cavity and consequent ignition of the molten plastic in contact with the hot air pocket (dieseling). 

Fig. 9. An initially aligned sample of rigid rod microtubule biopolymers in solution after it has been hit by radiation. The sample is viewed between crossed polarizers. The burn mark is centrally placed. The alternating dark and light bands are domains that have a different orientation. The transition from uniform alignment to domains with different orientation takes place in seconds after the sample is irradiated. The burn mark has dimensions of roughly 0.5 x 3 mm. The shift of the domains with respect to each other is approximately 0.5 mm as witnessed by the distortions of the bum mark.

The mass spectrometer was equipped with a 20-Hz N2 laser. The laser irradiation energy was adjusted by a neutral density filter and the beam size was adjusted to 35 xm with an adjustable pinhole placed close to the laser entrance window. The actual laser beam size was obtained by increasing laser fluence till a burn mark was left behind to allow off-line measurements of the laser beam footprint (rrrNote 6). 

Corrosion, One or more broken wires of the strand, Worn spots, and Burn marks. 

Recordkeeping Buckling at the ground line, Unusual angle to the ground, Cracks, Holes, Shell rot and decay, Knots, Depth of setting, Soft, wet, or loose soil, and Burn marks. A hammer and/or rocking test may also need to be conducted. None required. 

While cleaning melamine tableware is not tough, once it gets discoloured with frequent use and washing, it loses its appeal. Since scratches and burn marks cannot be removed from it, perhaps the best solution is to throw out the damaged pieces. 

Avoid free-standing ribs to minimize (a) air trapping in the blind hole and (b) the resulting burn marks and short shot. 

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