Transcript
Ho n es te k B eltin g (Xia m e n) C o ., Ltd . TEL: +86-592-5164780,
5164217 FAX : +86-592-5164708
A DD : No. 50, S im ing Industrial Zone , M eixidao , Tongan D istrict , X iam en, C hina 361100 B E T T E R
S O L U T I O N S
I N
P R O G R E S S
www.honestek.com
Transport and Storage Keep material from: ---direct sunlight ---high temperatures in conjunction with high humidity ---low temperatures or other extreme conditions. When rolled up,do not place material upright on its edge,but ---hang it on a pipe inserted in the packaging core ---or set it flat on a shelf or pallet. Material is avoided to creased or damaged by sharp edges when transporting.And tip the belt on its edges is also not an admissable way. The advisable method is,on a carrying rod, insert through the packing core, relying on fork lift,with lifting sling,handcart or similar device.Only remove packaging at fitting site rather than unroll or pull belt on dirty or uneven floor. Material can be kept in a cool and dry location, major fluctuations out of a standard and ideal environment of 20℃/50% humidity, may change resistance of surface materials. Before fitting, allow material to acclimate to ambient termperature. Splicing Methods The splice durability is a key to the belt life. Which splice is the best way is to rely on the flexibility and the splicing difficulty. The hot splice is the most durable and flexible type of splice. ①Z-splice The most stringent requirements for uniformity of thickness is mostly handled with Zsplice. Suitable for knife-edge belts, this method is a standard belt splice of mono-layer and two fabric plies. ②Stepped Z-splice In the harsh operating conditions(e.g.dirty drums), the joints also keep up with the operation. Same properties as the Z-splice, further used in two and three fabric plies types. ③Wedge splice Splice way used for solid-woven belts and NOVO types. ④Overlap splice Especially suitable for two and three fabric plies belts with duroplastic coating. Cold-press method This method is possible for fitting and repairing on-site, but the splice strength and flexibility must be paid attention to.
利用 pdfFactory Pro 测试版本创建的PDF文档 www.pdffactory.com
Machanical fasteners Machanical fasteners make it possible as follows: ---install rapidly dispensed with dismantling the conveyor or machine ---repair by inserting the same material only when damaged section ---joint speedily and easily Advisable fastners: ⑤—hook fasteners ⑥—clamp fasteners ⑦—plastic fasteners Fasteners can be inserted or hot spliced into the belt coating.
Calculation Method
The following factors to effect the tension of conveyor belts: ---The approximate amount of elongation of the belt owing to belt load. ---The belt length tolerance. ---The temperature,stop-and-go operation,etc. which may externally necessitate a higher elongation or tension than justify the allowance of a tension take-up reserve normally. Normally, an elongation at fitting in the range of approx. 0.1 – 1% is available to load, so that a tension take-up range of 1% belt length is adequate. And the tensioning weight must make sure of moving freely. To attain sufficient grip by the belt on the drive drum,the tensioning weight must achieve the minimum belt pull with gravity-operated take-up systems. The take-up unit can be allowable to install after the drive unit. And it’s now a wise use for a reversible conveyor by such a design.
When belt and pulley transmits the effective pull, the Frictional force would occur by the flat belt drives.Several shafts may be driven in opposite directions at one or the same time through the simple and inexpensive drives. Meantime, the following features of flat belt drives are also the theoretical considerations: 1. favorable elastic (dampening) quality 2. low running noise 3. highly precise and uniform running performance 4. high degree of efficiency (98-99%) 5. feasible speeds of 100 m/s or more 6. transmitted up to 60 kW/cm Definitions and description 2
利用 pdfFactory Pro 测试版本创建的PDF文档 www.pdffactory.com
In a standard conveyor,the belt runs over two ends drums of terminals in the light material handling sector. And the drive drum closely links up to the discharge end of the conveyor in the preferred configuration, which named a head drive. Under this configuration,the forces are utilized better, instead of that with a tail drive design. But for a large working load, the way of reducing the effective pull is to use the support rollers with long conveyor lines rather than skid plates.
Drums The following factors must be valued for the minimum admissible and large enough drum diameter: ---the effective pull to be transmitted ---the flexural properties of the belt type used ---the flexural properties of the lateral and longitudinal proiles welded onto the belt If the drums with too small a diameter but wide conveyors, the unwanted belt would exclude large deflection as a result of creasing and mistracking. It’s a recommendation that,for the cylindrical section with tapered edges of the drive drum, the length is b/2. And the proportions of the drive drum is determined where belt width is considerably less than the drum length. Take-up devices How the contact pressure of the belt on the drive drum to transmit the effective pull, it’s elongating the belt with a tension take-up. The end drum can serve as a tensioning drum if it is stalled such that it can be moved by screw tension take-ups while remaining parallel to the drive drum. A fixed tension take-up does not allow any length compensation,which results from variations in elongation when start-up or with fluctuating loads or temperatures. On very long,heavily loaded conveyor, and to compensate immediately for elongations in the upper strand when working, the tensioning unit must be positioned close to the drive drum.
Belt support Both skid plate and roller design can be used for supporting belt. Skid plates with chamfered edges should be set approx.2-3mm lower than the belt. And aslo, skid plates must be aligned precisely since they have a profound effect on belt tracking as a result of sliding friction. Skid plates necessitate thoroughly clean ahead of the conveyor start-up, in case that remnants of protective lacquer coatings or other types of contamination cause considerable difficulties. 3
利用 pdfFactory Pro 测试版本创建的PDF文档 www.pdffactory.com
Exclusively, support roller bearings are almost used on the condition of low seal friction, because of the low rotational resistance and balanced running of support rollers. In order to keep a low centrifugal momentum, support rollers are usually consisted of precision steel tubing or steam tubing.
Knife edges Energy consumption by the belt rised when it runs over knife edges. In the meantime, due to friction in the knifeedge zone,belts running at high speed can be subjected to a substantial temperature goes up. In consequence, the arc of contact should be maintained up to a minimum. With a movable roller, the frictional force at the knife edge is substantially reduced.
Belt tracking and adjustment Make sure the conveyor and belt can work together well, the fundamentals are important as follows: ---The conveyor must not be distorted by the forces exerted by the belt, just as rigid as it should be. ---All the drums and rollers,especially the drive drum,must be clean. ---Knife edges,drive and end drums and support rollers should be aligned and parallel. ---Goods ought to be always loaded onto the centre of the belt in the direction of travel. A conveyor belt is tracked to the centre of the conveyor by a tapered or cylindrical drum. The higher the belt speed with the larger the drum diameter,the greater the centring effect.
4
利用 pdfFactory Pro 测试版本创建的PDF文档 www.pdffactory.com
Cleaning devices The effctiveness of how to clean the belts depends mostly on the particular circumstances. One or more scrapers with plastic or rubber blades will suffice in many instances, which mounted in a frame of flat or profile-section steel set at right angles to the direction of belt moving. ---The belt scraper should be possibly set close to the belt or touch it lightly. ---Plough-type scrapers are always places next to the end drum on the return side. ---Steel scrapers can be used to keep unlagged drums clean.
5
利用 pdfFactory Pro 测试版本创建的PDF文档 www.pdffactory.com
