Scraper slag conveyor
Scraper Slag Conveyor (SSC)
1 General Introduction
Based on the advantages of the traditional slag conveyor, we have improved our company’s slag conveyor after years development and research to make it have good performance and quality, which make the machine has a leading position in the industry. It has a good reputation among the users and highly praised by them.
2 Technical Characteristics
2.1 Rectangular Scraper instead of Triangular Scraper
The traditional slag conveyor scraper in triangular shape has disadvantages as that the wearing strip of the scraper will be abraded very soon to cause the abrasion of the scraper, resulting in the falling off of the sealing plate, and the performance of the replaced welded wear strip is poor, all that has limit the service life of the scraper. The using of the rectangular scraper has solved the short service life problem.
The rectangular scraper has the same advantages with the triangular scraper, such as good rigidity, big bearing capacity, not easy to deform, and high return slag cleaning rate especially at the rear tension roller position. Meanwhile, it has improved the wear resistance performance and perfected the repeated repairing performance.
2.2 Forged Hinge Pin
The hinge pin of the old type slag conveyor is fabricated by casting, which has deficiencies that may influence the safe operation, such as shrinking and loosening, air hole and sand hole, and easy to break. While the forged hinge pin is fabricated by the precision die forging forming technology, the structure is compact and strength is high, which has no the deficiencies of the casting hinge pin. The material of the forged hinge pin is CrMnTi alloy steel, taking carburizing and quenching to improve the wear resistance. In order to avoid the falling of pin shaft, the anti-rotating structure is used to connect the pin shaft and the hinge pin.
2.3 Hydraulic Tension Device with Non-return Mechanism
The chain tension device of the slag conveyor is the new hydraulic automatic tension device equipped with single direction mechanical non-return mechanism. The working chain and return chain are sliding operating mechanism, forming a reliable tension device. It can keep a constant tension force, absorb the increment of the abraded drive chain, ensure the chain and scraper in full tight condition during working, make the slag conveyor operate stably, reduce the friction resistance between the scraper and the bottom plate, avoid falling off of chain and jamming of chain, help to take off the chain, and lower the working strength of the workers. It can achieve remote monitoring, and the tension stroke is 400mm – 600mm.
The tension device has equipped with single direction mechanical non-return mechanism, which can avoid the tension block falling back due to increasing load of slag conveying, and prevent the tension shaft falling down caused by sudden pressure loss or leaking of the hydraulic system. The oil cylinder adopts double-sleeve structure and has manual pressure pump. The interlayer of the two sleeves is the oil accumulating cavity. Under normal working condition, the electric oil pump of hydraulic station will supply pressure oil to the oil cylinder, and the accumulator will keep the pressure for a certain period and supplement pressure oil. When the hydraulic station system has malfunction, the oil supply loop can be switched to the manual pressure pump to force the rear tension wheel directly. The tension support of the new tension device has been strengthened to prevent the deformation.
2.4 Characteristics of Composite Structure Guide Chain Gear
The steering wheels, including inner guide wheel, tension wheel, and rear guide wheel, of the old-type slag conveyor are whole set casting component, and the wheel rim is always being abraded very soon, sometimes even causes shut down of the slag conveyor. For this issue, our company has adopted composite type steering wheels, which has obtained a good result.
The size and specification of the composite type steering chain wheel is the same to the original one and changeable. The steering chain wheel body adopts split heat charging structure, the guide wheel body uses cast steel, the wheel rim connecting with the chain and scraper uses wear resisting steel, the service life of the wheel body has improved by 2 -3 times.
2.5 External Bearing Type Inner Guide Wheel
Different to the normal internal bearing type inner guide wheel, the slag conveyor of our company adopts external bearing type inner guide wheel. The bearing chamber is set at the outside of the casing, isolating from the dirty water inside of the casing, which has ensured that the water do not directly contact with the bearing so that can guarantee the service life of the bearing, extend the inner guide wheel, and improve the reliability of the guide wheel.
2.6 Forged Tooth Type Drive Chain Gear
The drive chain gear of the normal slag conveyor adopts casting technique and do not take hardening treatment, having the shortcomings as low bearing capacity, easy to have tooth break, poor accuracy of the tooth, not resistant to wearing, short service life, and not reliable fixing. In order to solve those shortcomings, our company has changed the drive chain gear to forged concave tooth chain gear as shown below.
The gear is formed by precision die forging, using good qualified alloy steel and taking hardening treatment, which makes it have advantages as high bearing capacity, high accuracy of tooth, stable transmission, wearing resistance, long service life, and firm fixing.
2.7 High Performance Wear-resistant Cast Stone Liner Plate
The tank bottom plate of the slag conveyor adopts basalt cast stone liner made according to “anti-broken and anti-falling off lining technology”, which has characteristics as anti-wearing, anti-impact, anti-corrosion, and long service life. Compared with the metal liner, the 400mm thick basalt cast stone can bear more heavy impact, having more excellent anti-friction and anti-corrosion feature, and lower friction resistance, which is conducive to improve the service life of the scraper. The service life is no shorter than 100,000 hours.
Install fall-off preventing framework (orifice plate) to the bottom plate of the slag conveyor before the installation of cast stone. The upper surface of the orifice plate should be flush with the upper surface of the cast stone. The connecting holes of the orifice plate will be full of cast stone slurry while grouting the arranged cast stone, which will have the anchor function to enhance the connection between the cast stone. Another function of the orifice plate is that when some of the cast stone fall off, the plate will work as framework to ensure the operation plane surface of scraper and chain keep above the cast stone surface and will not cause large area falling-off of the cast stone.
The wear resistant cast stone is arranged at a direction that forming a certain angle with the running direction of the scraper of the slag conveyor, which can not only guarantee the firmness of the arrangement for cast stone but also the uniformity of the wearing for scraper.