Special points of interest: Two centrifuge manufacturers that produce machines with similar special features that distinguish them from the other brands that are present today on the North-American market. Features like the open scroll and the independent scraper have proven their advantages in the past. FEATURES COMPARED (Click on item in the left column to go to details) PIERALISI DRYCAKE/CBB Replace sludge discharge bushings 1-2 days Hardened steel Minutes Silicon carbide Replace sludge scraper mechanism 1-2 days 1 hour Access to liquids weir plates Difficult access Easy access Scroll feed inlet Open scroll construction Hard surfacing Standard: No protection Hollow steel structure Narrow slots Castolin Eutalloy CPS 1229 Standard: Tungsten carbide spray Solid bar steel Wide slots Tungsten carbide flame sprayed by hand G-FORCE High G machine up to 18.5 diameter 25.5 diameter Removing the rotating assembly 1/2 day 1 hour
SLUDGE DISCHARGE BUSHINGS Pieralisi Bushing CBB Bushing Replacing the sludge discharge bushings The sludge discharge ports are usually the first affected by wear of the decanter. All dehydrated solids are removed through these bushings. PIERALISI: The bushing have to be removed from the inside In order to replace the bushings, the scroll has to be removed from the drum. Consequently because of this operation, it is advisable to replace the seals and eventually even the bearings. Replacing the bushings represents almost the same labor as an overhaul, takes several hours and requires other parts to be re-placed. CBB: The parts are kept in place with an external mounting that can be replaced without special tools and only takes minutes MATERIALS OF CONSTRUCTION Pieralisi hardened steel CBB Standard: Silicon carbide
SLUDGE DISCHARGE BUSHINGS
SCRAPER MECHANISM Driven by a chain running around a copper bushing in order to replace the complete machine has to be disassembled Mechanism with gears and roller bearing. The slow moving bearings have unlimited life span. Limited lifespan because of wear of the soft bushing
SCRAPER MECHANISM
FEED INTAKE Hollow sheet metal Full bar sheet Pieralisi: Standard: no extra protection. The scroll is built around 4 hollow sheet metal that are welded together. When perforated, re-welding is virtually impossible. For larger models (jumbo and larger) a protection plate can be welded in. However, when this plate gets removed because of wear on the welds, extreme damage can be done to both the scroll and the drum interior. Because the pipes are hollow, the opening or solids intake with is reduced CBB: The scroll is built around 4 bar steel metal pipes that welded together. Even after extreme wear, it can always be repaired.
LIQUID WEIR PLATES
SCROLL Open scroll construction: Because of the open scroll construction, the feed pipe can be adjusted with an optimal precision. This can be done while the machine is in full operation Pieralisi: The scroll is built around 4 hollow sheet metal pipes that are welded together. When perforated, re-welding is virtually impossible. Slots are narrow, not leaving a lot of space for hardsurfacing. Standard: AISI304 CBB: The scroll is built around 4 full bars metal pipes that are welded together. The solid plate has a much longer life span and can always be built up by welding. Slots are wide for all models Standard: AISI 304
HARDSURFACING Castolin Eutalloy CPS 1229 Tungsten carbide flame sprayed
G-Force and dimensions Model Main motor power (kw) Drum revolution max rpm Centrifugal force max x g Slenderness ratio L/D Length Drum diameter inches Drum diameter (mm) Hydraulic capacity L/H Pieralisi Baby 1 5.5 5200 3500 2.43 564 9.1 232 2500 Pieralisi Baby 2 7.5 5200 3500 3.33 773 9.1 232 4000 Pieralisi Baby 3 7.5 5200 3500 4.20 974 9.1 232 5000 Pieralisi FP 600 / M 11 4100 3300 2.62 925 13.9 353 6000 Pieralisi FP 600 RS / 11 4100 3300 3.48 1228 13.9 353 9000 M Pieralisi FP 600 2RS / 15 4100 3300 4.32 1525 13.9 353 12000 M Pieralisi Jumbo 1 30 3350 2950 2.51 1180 18.5 470 25000 Pieralisi Jumbo 2 37 3350 2950 3.38 1589 18.5 470 35000 Pieralisi Jumbo 3 45 3350 2950 4.25 1998 18.5 470 45000 Pieralisi Jumbo 4 45 3350 2950 5.12 2406 18.5 470 55000 Pieralisi Mammoth 2 45-47 2700 2350 3.92 2234 22.4 570 65000 Pieralisi Mammoth 3 55-90 2700 2350 5.10 2907 22.4 570 85000 Pieralisi Giant 2 75-110 2000 1570 3.59 2513 27.6 700 110000 CBB CD 25 5.5 6000 4400 3.64 800 8.7 220 5000 CBB CD 30 S 7.5 6000 5800 3.45 1000 11.4 290 7000 CBB CD 30 SI 11 6000 5800 3.45 1000 11.4 290 9000 CBB CD 30 11 6000 5800 4.48 1300 11.4 290 10000 CBB CD 30I 11 6000 5800 4.48 1300 11.4 290 12000 CBB CD 40 S 15-18,5 4200 3724 3.42 1300 15.0 380 15000 CBB CD 40 SI 15-18,5 4200 3724 3.42 1300 15.0 380 18000 CBB CD 40 18,5-22 4000 3378 4.34 1650 15.0 380 20000 CBB CD 40 I 18,5-22 4000 3378 4.34 1650 15.0 380 25000 CBB CD 50 S 45 3500 3437 3.37 1700 19.9 505 40000 CBB CD 50 SI 45 3500 3437 3.37 1700 19.9 505 45000 CBB CD 50 55 3500 3437 4.26 2150 19.9 505 53000 CBB CD 50I 55 3500 3437 4.26 2150 19.9 505 55000 CBB CD 65 S 75 2800 2831 3.31 2150 25.6 650 65000 CBB CD 65 SI 75 2800 2831 3.31 2150 25.6 650 70000 CBB CD 65 90 2800 2831 4.08 2650 25.6 650 75000 CBB CD 65 I 90 2800 2831 4.08 2650 25.6 650 85000 CBB CD 80 160 2100 1948 3.96 3150 31.3 795 100000 CBB CD 80 I 160 2100 1948 3.96 3150 31.3 795 120000
REMOVING THE ROTATING ASSEMBLY