Charcoal filters in a respirator will remove the vapors for a period of time If

Charcoal filters in a respirator will remove the

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Charcoal filters in a respirator will remove the vapors for a period of time. If you can smell the resin vapor safer placing the mask back on after a break, replace the filters immediately. Some times ,charcoal filters last less than 4 hours. Store the respirator in a sealed bag when not in use. If working with toxic materials for an extended period of time, a supplied air mask and hood are recommended. Avoid skin contact with the fibers and other particles by wearing long pants and long sleeves along with gloves or barrier creams. The eyes must be protected using leak-proof goggles (no vent holes) when working with resins or solvents because chemical damage to the eyes is usually irreversible Aluminium 7075 was also considered for low stress areas. High strees areas required materials such as fiber based composite with either a thermoplastic or thermosettings matrix.the wing of the aircraft needs very high strength components , so varies of composite is consider for spar are listed below. The skin is made out of HEXCEL with a high temp thermoplastic matrix with honeycomb core. The thermoplastic CELAZOLE(R) POLYBENZIMIDAZOLE OR PBI is used as the matrix material in high heat areas because it can withstand 580 0 F for over 20000 hrs before degrading. The material properties can be seen below. The wing use spectra 1000 as the fiber as it has as higher strength compared to hexel. The matrix material for spectra 1000 parts is RIP3000, A low temp matrix matrial that has a mould temperature below the critical temp of 147 0 C of spectra 1000. The spars also contain a honeycomb core to prevent buckling of the load carrying spectra by increasing the stiffness of the panel and up to 37 times the stiffness, if the core is 4 times the plate’s thickness. The honeycomb used in aluminium based material because it has highest strength to weight ratio.
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Other areas that are used composite are longerons and control surfaces. The forward fuselage longerons are the made of spectra fibers and the rear longerons are made of HEXCEL. The HEXCEL is required for rear longerons as they undergo the heat produced by the engine. The control surface are made of HEXCEL based skin, thermoplastic flanges will be attached to the bulkheads. The thermoplastic of flange and adjoining piece can then be heated locally to bond the flange and adjoining piece together. COMPOSITE COMPARISONS MATERIAL DENSITY MAX STRENGTH MAX TEMP HEXCEL CARBON FIBER AS4C 15 0.0643 lb/in^3 602000psi HONEYWELL SPECTRA 1000 14 0.035 lb/in^3 4350000psi 147 0 C DUPONT KEVALAR 14 0.052 lb/in^3 4350000psi 149 0 C THORNEL T-300 PAN 14 0.0636 lb/in^3 529000psi SGL SIGRAFIL C S009 14 0.065 lb/in^3 522000psi THERMOPLASTIC USED AND THEIR PROPERTIES MATRIX MATERIAL DENSITY MAX STRENGTH MOLD TEMP MAX TEMP Celazoile(R) Polybenzimidazole PBI 14 0.047 lb/in^3 23200psi 310 0 C RTP 3000 14 0.0303 lb/in^3 3500psi 93.3 0 C 250 0 C METALS: METALS such as aluminium are a staple in aircraft structures. Aluminium is a material with strength to weight ratio better than steel and is a very high strength material and has very good high temp properties,so it will be used around the engine to shield the composite longerons from the extreme engine heat . aluminium lithium is lighter than typically 7075
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