Continuous glass

Polyurethane, PVC, and extruded polystyrene provide the bulk of the cellular plastics used for low and cryogenic temperature appHcations. In some cases, eg, the insulation of Hquid hydrogen tanks on space systems, foams have been reinforced with continuous glass fibers throughout the matrix. This improves strength without affecting thermal performance significantly. 

AH forms and compositions of reinforcements, ie, mats, woven roving, glass, carbon, and aramid, are commonly used with these processes. Special continuous glass strand mats with a thermoplastic binder aHow preforms to be made using thermoforming techniques. These processes are used for tmck and autobody components, medical equipment cabinets, transportation seating, and other parts needed in the intermediate volume range (1,000—10,000 parts/yr). 

In commercial practice, chlorination may be carried out either in batches or continuously. Glass-lined or nickel reactors may be used. Because certain metallic impurities such as iron catalyze ring chlorination and self-condensation, their presence must be avoided. The cmde product is purged of dissolved... 

A reinforced plastic sheet is to be made from a matrix with a tensile strength of 60 MN/m and continuous glass fibres with a modulus of 76 GN/m. If the resin ratio by volume is 70% and the modular ratio of the composite is 25, estimate the tensile strength and modulus of the composite. 

A filament wound composite cylindrical pressure vessel has a diameter of 1200 mm and a wall thickness of 3 mm. It is made up of 10 plies of continuous glass fibres in a polyester resin. The anangement of the plies is [O3/6O/ — 60],. Calculate the axial and hoop strain in the cylinder when an internal pressure of 3 MN/m is applied. The properties of the individual plies are... 

A polyester matrix is reinforced with continuous glass fibres. A 15 mm wide beam made from this material is to be simply supported over a 300 mm length and have a point load at midspan. For a fixed beam weight of 90 g/m investigate how the stiffness of the beam changes with the volume fraction of glass and state the optimum volume fraction, (p/ = 2560 kg/m. p , = 1210 kg/m Ef = 76 GN/m = 3 GN/m ). 

Electrodes - continued glass, 555, 557 glassy carbon, 613 graphite, 613... 

Different methods are used for manufacturing SMC. A few will be reviewed. Figure 8-59 shows continuous glass-filament rovings going through a chopper (where the length... 

Mat and continuous glass fibre reinforcements theoretically all the thermoplastics are usable in these forms, but up to now developments have concentrated on polypropylenes (PP), polyamides (PA) and thermoplastic polyesters (PET) fibre-reinforced PEEK, polyetherimide (PEI) and polyphenylene sulfide (PPS) are used for high-performance applications. They are presented in a range of forms from stampable sheets to pellets, prepregs, ribbons, impregnated or coated continuous fibre rods. More rarely (as in the case of PA 12, for example), the thermoplastic is provided in liquid form. 

The mat and continuous glass fibre reinforced grades have specific uses ... 

Technical advantage/function Basalt rock wool is used for noise insulation in automotive exhaust units for the purposes of noise absorption. Vital technical requirements are temperature resistance, noise absorption behaviour, corrosion resistance and mechanical stability. Now textile continuous glass fibres and biosoluble mineral wools are also used for this application in exhaust units. 

Loewenstein, K. L. (1973). The Manufacturing Technology of Continuous Glass Eibers. Elsevier, New York. 

Loewenstein KL (1993) The Manufacturing Technology of Continuous Glass Fibers, 3rd edn., Elsevier, Amsterdam... 

The major reinforcing phase is typically continuous glass roving, which is a bundle composed of 1000 or more individual filaments. The most common glass roving used... 

Spray-Up. Instead of hand lay-up, continuous glass roving and liquid resin are fed into a gun, which chops the glass fiber, mixes it with the resin, and sprays it into the mold. This can be automated for lower labor cost and greater uniformity. Spraying is often followed by hand-rolling to expel air and density the assembly. Then it is allowed to stand until cured. Products are similar to those from simple hand lay-up. 

A new technology, based on impregnating continuous glass fibres with an extruded low viscosity PVC melt and subsequent application via the extrusion die of a standard PVC extrudate, has given PVC profiles with a 500% increase in stiffness (201). 

M.N. Bureau, J. Denault, Fatigue resistance of continuous glass fiber/polypropylene composites consolidation dependence, Composites Science and Technology 64 (2004), pp. 1785-1794. 

Calculate (a) the modulus of elasticity, (b) the tensile strength, and (c) the fraction of the load carried by the fibers for a continuous glass fiber-reinforced epoxy resin, with 60% by volume E-glass fiber, stressed under isostrain conditions. The tensile strength and modulus of the fibers are 1800 MPa and 76 GPa, respectively, and the values of these quantities for the matrix are 60 MPa and 2.4 GPa, respectively. 

A unidirectional laminate consists of continuous glass fibers in an epoxy matrix and has a 60% fiber volume fraction. Calculate the strains (a) when a tensile stress of 100 MPa is applied in the fiber direction and (b) when a stress of 20 MPa is applied in the direction transverse to the fibers. The tensile moduli and Poisson s ratios for the glass and epoxy are Ef = 80 GPa, Em = 2.5 GPa, Vf = 0.2 and = 0.35, respectively. 

The off-gas from melting of mixtures of salt cake with either basalt and B2O3 or sand and lime consists mainly of NO and CO2 from decomposition of nitrate, nitrite, and carbonate salts. The off-gas will also contain water vapor and, possibly, traces of SO2. Not unexpectedly, some radio-cesium also volatilizes when salt cake is converted to glass at 1100°-1200°C. Our laboratory-scale tests suggest, however, that of the order of 5%, or less, of the radio-cesium will volatilize when salt cake is converted to glass in a conventional continuous glass melter. 

Another example of the two-dimensionally reinforced foamed composite was developed by Celotex Corp., USA. The production process consists of the use of continuous-glass-strand mat and a horizontal conveyer process. Continuous-strand mat is supplied on a moving horizontal conveyer. The foaming mixture is then applied onto the glass mat through the mixing head of a dispensing machine (35). 

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