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Design and Manufacturing of Disc Refiner

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Design and Manufacturing of Disc Refiner International Journal of Emerging Technology in Computer Science & Electronics (IJETCSE) ISSN: 0976-1353 Volume 21 Issue 3 – APRIL 2016. DESIGN AND MANUFACTURING OF DISC REFINER S.Hanish Anand[1], P.Manigandan [2]J.Satish Kumar[3], J.Evan Cephas Jeffrey[4], Assistant Professor, Mechanical, Kings Engineering College, Chennai, India 1 Assistant Professor, Mechanical, Kings Engineering College, Chennai, India 2 Student, Mechanical,Kings Engineering College ,Chennai, India 3 Student, Mechanical, Kings Engineering College, Chennai, India 4 important aspect of the process, as it is here that the Abstract— Refining or beating of chemical pulps is the mechanical characteristics of the cellulose fibres and the composition of the treatment and modification of fibres so that they can be formed into papermaking furnish that comprise paper are determined, which paper or board of the desired properties. It is one of the most affect how the fibres bind with each other during the formation important unit operations when preparing papermaking fibres for high-quality papers or paperboards.For which various instrument of the paper web and what the various optical, structural, and were used of which first beater commonly called as Hollander chemical properties of the paper will be good. beater in which various problems are occurred. But various refiners have now replaced beaters and the term "refining" is 2.1HOLLANDER BEATER widely used. In fact, both terms are synonymously used, but here There are two basic methods for pulp refining. The the term "refining" is used to describe the work accomplished with refiners on the fibres.The mostly used is disc refiner, the common first, an older batch system, uses an oval tank called a beater. advantage is lees labour, area and more efficiency is achieved. In The beater is equipped with rotating metal bars that squeeze the general disc refiner produced in the industry uses 30-40 HP motor fibres between stationary metal bars. The water-suspended fibres to produce 7 tonnes per day but in our project we introduce are repeatedly passed through the rotating bars, the end result of concept of using 5 HP motor to produce 6 tonnes per day. which is that the fibres become frayed, shortened lengthwise, swollen in diameter and softened. Their surface area is increased Index Terms— Refining, fibres, to facilitate the binding of fibres in subsequent stages of the papermaking process. Loading, or the addition of non-fibrous .INTRODUCTION additives such asfillers, can take place at this point. The furnish Refining is a fundamental operation in the manufacture is sent to a conical refiner (also called a jordan) for further of paper considering its importance on the final paper properties. refining. The furnish enters at the smaller end of the conical It is the only operation that modifies pulp fibre morphology, refiner, is swirled between a rotating plug and stationary metal shaping the paper with the desired optical, physical and printing bars and is ejected out the larger end. In larger papermills, the properties. At the present time, with paper machines running at beater/refiner batch system has been replaced by continuousdisk 2000 m/min, it is of greatest importance that refining should be a refiners, which are rotating disks having serrated or otherwise fully known and controlled process, so as not to adversely affect contoured surfaces. One disk rotates clockwise, while the other machine productivity or exceed planned output costs. Refining rotates counterclockwise, or is stationary. The furnish is pumped can be described as an operation which, through transmission of through the center of one of the disks and as centrifugal force mechanical energy from the refining plant, irreversibly changes throws the furnish toward the perimeter of the disks, it is the structural morphology of pulp fibres. This is done by passing sandwiched between them. The action of the rotating disks rubs, an aqueous suspension of fibres through the gap between two rolls, cuts, frays, and softens the fibres. The space between the slotted surfaces, one of which is stationary (stator) and the other disks can be adjusted, depending on the degree of refining moving at high velocity (rotor), with a minimum distance desired. In continuous refining systems, the type of pulp, the between them, so that energy of friction is transmitted providing degree of refining, and the type and quantity of fillers can be the necessary rubbing to refine the fibre. Despite various altered easily depending on the type of paper that is to be experimental publications, very few have attempted to produced. understand the physical nature of refining. The mechanical treatment of paper pulp fibres to impart to them the appropriate characteristics for papermaking. A part of the stock preparation phase of papermaking, refining is the most 79 International Journal of Emerging Technology in Computer Science & Electronics (IJETCSE) ISSN: 0976-1353 Volume 21 Issue 3 – APRIL 2016. 3.2EFFECTS OF REFINING During refining, the primary and secondary walls of the fibre break and are partially removed. The penetration of the water to the inside is therefore possible, causing swelling. It also permits the release of internal fibrils which separate and produce a formation of finer micro fibrils on the surface of the fibre. 2.2CONICAL REFINER It is the second oldest refiner. In the group of the conical refiners, the first machine was a Jordan-type shallow angle conical refiner with a thoroughgoing shaft. Cone angle of these refiners is approximately 10°and, as fillings often are quite coarse, these refiners are considered to give fibre cutting refining result. However, when fillings (plug and shell) with narrow bars are used, these refiners do excellent fibre development and are suitable for all kinds of fibres. Due to the difficult change of fillings and long low-capacity machine, the number of these machines in use is decreasing. The next conical-type refiner is a Claflin-type wide angle refiner Owing to all these effects, the fibre becomes more .Basically the construction is close to a Jordan-type refiner, with flexible and softer, at the same time increasing its surface and the only differences being shorter fillings with a wider 30°cone specific volume. All these effects can be grouped into three: angle. Hydration Fibrillation Trimming 3.REFINING 3.1REFINING PROCESS Refining and stock preparation are some of the most critical phases, prior to actual paper making. The whole paper making potential of the raw materials should be taken into use with minimum amount of energy consumed 3.3FORCES CREATED DURING THE REFINING The refining stage in stock preparation plays an important role There are many forces created during the refiner. Although in developing the properties of stock for paper production. energy being an easier and a more common variable to handle in Appropriate fibre treatment in the refiner greatly affects the run the paper mills, force is the prime variable in low consistency ability of the paper machine and quality of the end product. On refining. It is largely accepted that are three the forces acting in the Figure was presented mechanical treatment of fibres inside refining: normal force, shear force and corner or edge force, disc refiner. which are shown in the following diag 80 International Journal of Emerging Technology in Computer Science & Electronics (IJETCSE) ISSN: 0976-1353 Volume 21 Issue 3 – APRIL 2016. Max. speed 3600 rpm Nominal torque 16.2 N-m Max. torque 487 N-m Moment of inertia 0.01811kgm2 Torsional stiffness 41 N-m/0 Tyre gap 3mm Fig. FORCES ON REFININ 4.DESIGN AND CALCULATION 4.1.CALCULATION OF BEARING Diameter of the shaft - 43.5mm Speed - 960 rpm Radial load - 500 N Thrust load - 1000N For this shaft diameter and for our requirement ,we selected 4.3.BENDING MOMENT OF SHAFT “self aligning bearing” Transmitting torque : From PSGDB 4.16 “SKF2207”is selected Mt = p × 60 / 2 For dia 45mm Mt = 3710 × 60 / 2π × 960 3 Static load capacity -10200 N Mt = 36.90 × 10 N-mm Dynamic load capacity -18000 N From PSGDB 4.4 W = Mt / 60 = 36900/60 = 615 N e = 0.37 Reactions on the shaft : X = 0.65 , Y = 2.6 RB × 635 = ( 200 × 2.45 ) + ( 220 ×2.45 ) S = 1.2 ( for rotary machine ) RB = 1.620 N P = 3510 N RA = 3.280 N Bending moment at A & B = 0 From PSGDB 4.6 for 960 rpm and 2000 hours B.M at C = 721.6 N c/p = 4.93 B.M at D = 656 N C = 4.93 x 3510 = 17304.3 N Equivalent twisting moment = 948.12 N since the dynamic load is less than the required 4.4TORQUE FOR SHAFT dynamic load capacity Power = 5hp 1hp = 746watts 18000 N > 17304.3 N 5hp = 746 × 5 = 3730watts Design is safe Motor speed = 480rpm To calculate torque P = 2πNT/60 T = {60×3730}/{2×π×480} = 74.24 N-m Motor torque T = 37.10 N-m ADVANTAGE OF DISC REFINER 4.2.TYRE COUPLING Type of bearing F type It is used for reduction of time From the size of the bore we have selected F70 size It gives better perfomance when compared to Power rating for 960 rpm 16.30 Kw hollander beater,conical refiner. It gives more efficiency 81 International Journal of Emerging Technology in Computer Science & Electronics (IJETCSE) ISSN: 0976-1353 Volume 21 Issue 3 – APRIL 2016. Maintenance will be less [5] Hietanen, S., Ebeling, K., Fundamental aspects of the refining process, PaperijaPuu – Paper and Timber, Vol. 72, No 2, 1990, p. 158-170. Easy to manufacture [6] Fahey, M. D. (1970). Mechanical treatment of chemicals pulps, Tappi J. Easy serviceability 53(11), 2050-2064 5.2.APPLICATIONS [1] It is mostly used small scale industries.
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