1、PDF外文：http:/ and fabrication of low cost filament winding machine F.H. Abdalla, S.A. Mutasher, Y.A. Khalid, S.M. Sapuan *, A.M.S. Hamouda, B.B. Sahari, M.M. Hamdan B. Abstract In general, the composite pipes are fabricated using glass fiber and polyester resin matrix by hand lay-up and also by 2-axi
2、s filament winding machine. In this work, a filament winding machine was designed and developed for the fabrication of pipes and round shape specimens. A lathe-type machine and a wet winding method were used in the design of the machine. It provides a capability for producing pipe specimens with an
3、internal diameter up to 100 mm and lengths up to 1000 mm. The range of the winding angle, or the fiber orientation angle, starts from 20 to 90 depending on the mandrel diameter used. Mandrel speed is kept constant as 13.6 revolutions per minute (rpm) while the speed of screw of delivery
4、unit varies from 0 rpm to a maximum of 250 rpm. In the filament winding process used, a single glass roving is drawn through a bath of pre-catalyzed resin which is mounted on the lead screw by the rotating mandrel. A control unit was used to control the whole process and achieve regular winding and
5、good surface finish. Tube samples and other circular specimens of different dimensions were produced using this machine for the different mechanical tests and applications. Keywords: Filament winding； Composite tube； Glass fiber； Matrix； Fiber orientation angle 1. Introduction Filament winding has e
6、merged as the primary process for composite cylindrical structures fabrication at low cost. In this process, composite layers are successively wound on a rotating mandrel, as presented in Fig. 1. The layers may be wrapped at different angles varying from hoop layers, which are perpendicular to the c
7、ylinder axis, to helical layers which are at an angle to the cylinder axis. The construction of composite cylinder by filament winding consists of three major steps 1, the first is the design, which includes the selection of materials, geometry, and fiber orientations while the second is fiber place
8、ment, the mechanical means by which the fibers are placed in their proper positions. Finally, the third is the selection and control of conditions which must be maintained during the Fig. 1. Schematic of the wet filament winding process 1. manufacturing process. A process for fabricating a co
9、mposite structure in which continuous reinforcements (filament, wire, yarn, tape, or other), either previously impregnated with a matrix material or impregnated during the winding, are placed over a rotating and removable form or mandrel in a prescribed way to meet certain stress conditions. The rei
10、nforced fibers are usually made of glass, Kevlar or carbon. Owing to simplicity of process, the hardware configuration is quite standard, and generally involves two main sub-systems； the rotary assembly and the delivery system.The rotary assembly consists of two structural blocks；one fixed and the o
11、ther linearly movable unit in which a 2-axis mechanically driven mandrel is mounted onto its holders. On the fixed end, the holder is connected to a rotating shaft, which is coupled to either a gear or a chain or belt reduction system, or directly to the motor unit. Generally, an AC or servo-motor i
12、s used because of its greater torque capabilities and accuracy when operating under conditions of heavy loading. For delivery system, rolls of continuous fibers are fed into a resin bath which is mounted onto the carriage rails that are commonly placed overhead to provide greater workroom. Generally
13、, the shape is a surface of revolution and may or may not include end closures. When the required number of layers is applied, the wound form is cured and the mandrel removed. The material properties in each layer are constant but may vary from layer to layer. The mandrel is represented by a hollow
14、cylinder with uniform effective wall thickness. The mandrel and the cylinder are of equal length and are axisymmetrical, so that neither the geometry nor the properties vary in the circumferential direction. Filament winding is defined as 2 a technique which produces highstrength and lightweight pro
15、ducts； consists basically of two ingredients； namely, a filament or tape type reinforcement and a matrix or resin. The concept of filament winding process had been introduced in early 1940s and the first attempt was made to develop filament-winding equipment. The equipment that was designed in 1950s
16、 was very basic； performing thesimplest tasks using only two axes of motion (spindle rotation and horizontal carriage). By mid-1970s, machine design once again made a dramatic shift. This time the advancement of servo technology entered the realm of the machine design. High-speed computers allowed f
17、or rapid data processing, resulting in smoother motion and greater fiber placement accuracy. The 1980s and 1990s saw the increased use of computer technology. Computers and motion control cards became the essential pieces of hardware that were included in almost every machine. Machine speed control
18、was greatly improved； computer control systems could track position and velocity with increased accuracy. Additional axes of motions were also incorporated into machine design；allowing for four, five and even six axes of controlled motion. 2. Manufacturing techniques The properties of a composite pr
19、oduct are not only dependent on the properties of fiber and resin matrix, but are also dependent on theway by which they are processed. There are a variety of processing techniques for fabricatingcomposite parts/structure； resin transfer moulding, autoclave moulding, pultrusion and filament wi
20、nding. Out of these processes, filament winding involves low cost and is the fastest technique for manufacturing of fiber reinforced cylindrical components as high-pressure pipes and tanks. 3. Winding methods There are two different winding methods: (I) wet winding, in which the fibers are passed th
21、rough a resin bath and wound onto a rotating mandrel (II) prepreg winding, in which the preimpregnated fiber tows are placed on the rotating mandrel. Among these winding methods, wet winding is more common and widely used for manufacturing fiber reinforced thermosetting matrix composite cylinders. C
22、ompared with prepreg winding,wet winding has several advantages: low material cost； short winding time； and the resin formulation which can be easily varied to meet specific requirements. 3.1. Winding patterns In filament winding process, the winding tension can easily be controlled. Winding tension
23、, winding angle and/or resin content in each layer of reinforcement can be varied until the desired thickness and strength of the composite are achieved. The properties of the finished composite can be varied by the type of winding pattern selected. In general, there are three basic filament winding patterns which are as follows. 3.1.1. Hoop winding It is known as the girth or circumferential winding. In hoop winding, a high-angle helical winding approaches an angle of 90 . Each full rotation of the mandrel advances the band delivery by one full bandwidth as shown in Fig. 2.
