fiberglass mats According to the glass composition can be divided into
The roving is made of parallel raw wire or parallel monofilament. Twist roving according to the glass composition can be divided into: alkali-free glass roving and alkali glass roving. Production of glass roving used in glass fiber diameter from 12 ~ 23μm. The number of rovings is from 150 to 9600 (tex). The roving can be used directly in certain composite material forming methods, such as winding and pultrusion processes, which can also be woven into a roving fabric due to their uniform tension, and further chopped rovings for some applications The
(1) Twistless roving for jetting The roving for use in FRP injection molding has the following properties: (1) good cutting property, and less static electricity during continuous high speed cutting; (2) roving after twisting High efficiency, that is, high beam splitting rate, usually require more than 90%; ③ chopped after the original wire with excellent cover, can cover the mold in every corner; ④ resin soaked fast, easy to roll by roller Easy to drive out the bubble; ⑤ original barrel to improve the performance, uniform density of roving, suitable for a variety of spray gun and fiber delivery system. Spraying with roving is made of multiple strands of the original system, each strand of raw silk with 200 glass monofilament.
(2) SMC with roving SMC that is chip molding compound, mainly used for pressing automotive parts, bathtub, water tank board, cleaning tank, all kinds of seats
Wait. SMC with roving in the manufacture of SMC sheet cut into lin (25mm) length, dispersed in the resin paste, so the requirements of the roving for SMC with twist is good, less wool, antistatic excellent , The chopped wire does not adhere to the knife roll during cutting. For colored SMC, the roving is impregnated with resin in a high pigment content resin paste. Usually SMC roving is generally 2400tex, a few cases also useful 4800tex.
(3) winding with roving winding method for the manufacture of various caliber of the glass pipe, tanks and so on. The number of twistless rovings is from 1200 to 9600, and the large pipes and tanks are mostly inclined to direct roving, such as 4800tex direct roving. The requirements for twisting roving are as follows: ① into a good band, was flat ribbon; ② roving easy to solve the good, in the bobbin from the release when not off, do not form a "nest" ③ uniform tension, no overhanging phenomenon; ④ linear density uniformity, generally less than ± 7%; ⑤ roving penetration of good, from the resin tank through the resin when easy to wet and soaked. (4) pultrusion with roving shrinkage for the manufacture of cross-section consistent with the various profiles, which is characterized by high glass fiber content, one-way strength. Pultruded roving can be multi-stranded wire can also be a direct combination of roving, the linear density range of 1100 to 4400. A variety of performance requirements and winding twist roving roughly the same.
(5) An important use of roving for roving yarnless weaving is to weave all kinds of square or unidirectional roving fabrics of coarse thickness, which are mostly used in hand-made FRP molding processes. Strong roving used for the use of non-twist roving: ① good wear resistance; ② good banding; ③ weaving roving in the weaving before the need for forced drying; ④ twist yarn tension uniform, Meet a certain standard; ⑤ twist roving easy to improve; ⑥ twist roving permeability is good.
(6) Tensile ropes in preforms In a preform process, the roving is routed and sprayed onto a predetermined shape of the web while spraying a small amount of resin to form the web and then forming the fibrous web Metal mold, into the resin hot forming, that is, products. The performance requirements for the roving of this process are essentially the same as those for jetting roving.