Used Technica Rotary Transfer Machine for sale (67,423)

Condition: good (used), functionality: fully functional, machine/vehicle number: C7154, Powtek - gericke rotary sieve housing: steel rotor: steel Bodpfevz Smmsx Aihewp inlet: stainless steel Ø300mm outlet: stainless steel Ø300mm transition sieve deck: nylon sieve deck 2mm coarse outlet: adjustable

Condition: refurbished (used), Year of construction: 2001, functionality: fully functional, Machining diameter: 4,000 mm Machining height: 850 mm Bwsdpfxjzfma Ej Aihep Control system: SIEMENS Tool holder: Grinding segments

Condition: used, Year of construction: 2009, CNC grinding machine Type/Model: Ri 8-4 Year of manufacture: 2009 Operating hours: 25,726 h Technical data Round table diameter: 800 mm Bwedpezh Hrtjfx Aihep Grinding diameter max.: 1100 mm Workpiece diameter max.: 1120 mm Workpiece height max.: 550 (700) mm Plunge depth max.: 300 mm Table load max.: 1500 kg Round table (C-axis) & guide Bearing: Hydrostatic guides in the X and C axes for maximum damping and wear-free operation Table drive: Direct drive Speed range: 0.01 to 200 rpm Positional accuracy: ± 1.5 arc seconds (smallest increment: 0.0001°) Tool holder & spindle (turret head) Number of spindle positions: up to 4 grinding spindles/tool positions in the automatically swiveling turret head CNC control & axis drives Standard control: Siemens Sinumerik 840D with extended Kehren application software X-axis: Linear drive Travel ranges (approximate values) X-axis (horizontal): approx. 1,200 mm Z-axis (vertical): approx. 700 mm Dimensions & weight Machine weight: approx. 20,000 kg + peripherals Equipment: - Coolant lifting unit Knoll FHA/300 - Emulsion mist separator Handte EM-DS - Platform with motor-adjustable platform for tool changes

Condition: used, Year of construction: 1995, rotary table diameter 600 mm Bedpfx Asy Nfdajihjwp boring diameter 600 mm grinding height 450 mm control Siemens Sinumerik 840 C total power requirement 30 kW weight of the machine ca. 14,5 t

Year of construction: 2009, condition: ready for operation (used), Equipment: height-adjustable conveyor, lid sorting and feeding system, conveyor belt with infeed and outfeed section, stainless steel construction, safety enclosure with interlocked safety doors, integrated electrical control cabinet and operator panel, the machine is designed to process Pano TO 100mm PP HOmao closures without liners. Inspection on site is possible. Bwjdpfozhw Tnjx Aihjp

Condition: good (used), Year of construction: 2010, Rotary table Fabr.WEISS Type: TC 220T Year: 2010. Bedpfx Aexr Dh Heihewp

Condition: used, Year of construction: 1969, rotary table diameter 1000 mm grinding height 500 mm grinding head - power requirement 15/5,5 kW total power requirement 30 kW weight of the machine ca. 18 t dimensions of the machine ca. m S I E L E M A N N (Germany) Hydraulic Rotary Table Internal and Face Grinding Machine with two grinding heads and with horizontal workpiece clamping Model RFsB 100 Year 1969 / fully reconditioned by the manufacturer in 1990 _____ Max workpiece Ø 1,000 mm Max. height of workpiece, approx. 400 mm Mounting height under grinding spindles approx. 500 mm Grindable Bore Ø, approx. 50 – 900 mm Max. Workpiece weight approx.. 900 kg Distance between Table bore and column 1.150 mm Table Ø / Face plate Ø, approx. 1,000 mm Table speeds, hydraulic, infinitely variable, right/left 5 – 60 rpm Table/workpiece infeed, 5 steps 0.0025 – 0.025 mm/stroke Table stroke approx. 500 mm Distance between grinding spindle and machine body 600 mm Surface Grinding Head Ø (Segmented wheel) 450 mm Grinding slides stroke, max. 500 mm Grinding slide speeds, infinitely variable 0.2 – 1 m/m Max. Internal Grinding spindle Ø 140/100 mm Grinding cup wheel Ø, up to approx. 200 mm Motor for Surface Grinding 15 kW / Motor for Internal Grinding Spindle 5,5 kW Total electrical load, approx. 30 kW - 380 V - 50 Hz Weight, approx. 18,000 kg Accessories / Special Features • The rotary table carries the workpiece and is also actuating the automatic grinding infeed • The relevant Grinding head can be swivelled in by turning the Column Bsdpfxsu Su Aps Aihjwp (hydraulic lift) so the workpieces can be ground in one setting with exact angles. • Built-on magnetic face plate, Ø approx. 1,000 mm, with 5 T-slots and stepless adjustment for the magnetism • Automatic workpiece infeed, with automatic depth stop. • Separate Height adjustment of internal grinding head, Grinding spindle Ø 100 mm. • Dressing devices mounted on each grinding head, Separate Switch Cabinet and hydraulic unit, • No Coolant Device available This machine is ideal for grinding bulky and heavy workpieces like housings, gears (!) bearing rings, cylindrical knives, etc. Condition: Good. Machine can be inspected soon under power Delivery : Ex stock as inspected. Payment : Net, after conclusion of contract.

Condition: used, Year of construction: 2011, controller manufacturer: Fanuc, controller model: 30i, _____ Description: Year of manuf. : 2011 Control : Fanuc 30i In General: Year of manufacture:2011 Control system:Fanuc 30i Maximum table load:100 kg Travel range X/Y/Z:300/300/370 mm Installation weight:approx. 33,000 kg Machining station I (X/Y/Z/B): Technology:1 x vertical spindle Speed:8,000 rpm Tool holder:HSK-A 63 Power:31 kW Torque:197 Nm Tool changer:12 stations B-axis:0.001°, pneumatic indexing, clamping force Tool diameter/length:125/250 mm Machining station II (X/Y/Z/B): Technology:1 x vertical spindle + 1 x horizontal spindle Speed:8,000 rpm Tool holder:HSK-A 63 Power:31 kW Torque:197 Nm Tool changer:12 stations B-axis:0.001°, pneumatic indexing, clamping force Tool diameter/length:125/250 mm Machining station III (X/Y/Z/B): Technology:1 x vertical spindle Speed:8,000 rpm Tool holder:HSK-A 63 Power:31 kW Torque:197 Nm Bwsdszfu Rfopfx Aihjp Tool changer:12 stations B-axis:0.001°, pneumatic indexing, clamping force Tool diameter/length:125/250 mm Machining station IV (X/Y/Z/B): Technology:1 x vertical spindle + 1 x horizontal spindle Speed:8,000 rpm Tool holder:HSK-A 63 Power:31 kW Torque:197 Nm Tool changer:12 stations B-axis:0.001°, pneumatic indexing, clamping force Tool diameter/length:125/250 mm Loading station: Numbers:2 pieces (front and rear) Equipment: Position measurement systems:Direct on all axes Chip removal:Chip conveyor Coolant supply:IKZ system, 30 bar Tool breakage monitoring:Artis, type CTM V5 Zero-point clamping system:Erowa Emulsion mist separator:Reven

Condition: excellent (used), Year of construction: 2017, operating hours: 15,200 h, functionality: fully functional, machine/vehicle number: P172ZH357, travel distance X-axis: 700 mm, travel distance Y-axis: 400 mm, travel distance Z-axis: 330 mm, nominal power (apparent): 11 kVA, overall weight: 2,200 kg, spindle speed (max.): 24,000 rpm, coolant supply: 40 bar, number of spindles: 1, number of slots in tool magazine: 21, Equipment: documentation/manual, Equipment: - FANUC DDR-T 4th axis digital rotary table with tailstock - high-pressure through-spindle coolant, 24,000 rpm - 200L chip conveyor with high-pressure pump - automated side door for robotic loading - machine under annual FANUC maintenance contract - optional extra: integrated Fanuc M20iA12L robot already mounted on the machine Bwedpfjzhi R Sox Aihjp

Condition: ready for operation (used), Year of construction: 2011, DELTA LC 500 - Rotary table grinding machine -CE marking -Magnetic table - rotary table, 500mm -Max. grinding diameter 500mm -Grinding height (distance table - grinding wheel) approx. 230mm -Grinding wheel dimensions (standard) 200x80x78mm -Speed - grinding spindle approx. 2850 rpm -Fine feed 0.01mm -Distance / column - grinding spindle axis approx. 320mm -Spindle motor 3 kW -Coolant system -Machine enclosure -Documentation Bjdjzflxaopfx Aihewp Dimensions: L x W x H 1.3 x 0.8 x 1.8 meters / (00 kg Errors and omissions excepted.

Condition: good (used), machine/vehicle number: RTT HAU T3, Used rotary table polishing machine Manufacturer: Hau Rotary table with 6 working spindles and 3 polishing stations with high-pressure nozzles, 5.5 kW motors, Bjdpfx Aeh Ug Uljihowp control cabinet.

Condition: used, Year of construction: 1976, We are selling a used rotary indexing table with four polishing stations. This rotary table is also equipped with four rotary unions. The polishing stations are designed for polishing wheels with a maximum diameter of 500 mm. The stations feature automatic feed. The drive power of the polishing stations is 5.5 kW. Bodpsxxv D Hofx Aihewp If you have any further questions, please feel free to contact us!

Condition: good (used), Used rotary indexing table polishing machine Manufacturer: Hau Rotary indexing table with 6 work spindles and 3 polishing stations with oscillation and high-pressure guns, Bodpfx Aoqmfv Sjihewp 5.5 kW motors, gripper clamping system, switch cabinet

Condition: used, machine/vehicle number: HR6-1200, Used rotary indexing table polishing machine HR6-1200 Manufacturer: Hau Bwedpfoyntrhox Aihop Rotary indexing table with 6 working spindles and 3 polishing stations equipped with high-pressure guns, 5.5 kW motors, Pneumatic clamping with Schunk PZN 100 clamping grippers, Schunk distributor. Control cabinet. Three rotary table polishing machines are available.

Condition: ready for operation (used), A Nagel + Hermann transfer and placement machine for transfer motifs (rhinestone, hotfix or similar) is available. Colors: unlimited, shapes: unlimited, production capacity: 5000elements/h, max. motif dimensions X/Y: 300mm/300mm, machine dimensions X/Y/Z: approx. 820mm/650mm/650mm, weight: approx. 120kg. Including PC notebook, CAD software, 4x conveyor plates, 2x mounting plates as well as various spare parts and tools. Documentation available. An on-site inspection is possible. Bsdpjzdul Tjfx Aihswp

Condition: good (used), Year of construction: 2017, 5-Axis CNC Machining Center MAKA DC 7 2 units of MAKA DC 7 for sale. High-performance CNC machining center for 5-axis machining of composite, GRP, and CFRP components, designed with a fixed portal structure. The machining unit is horizontal, and the table is arranged vertically. Machine type: MAKA DC7 Year of construction: 2017 Number of tables: 1 x rotary table for tandem operation Bsdpfxezgtyhj Aihewp Technical data: Travel distances: X-axis: approx. 3,900 mm Y-axis: approx. 1,300 mm Z-axis: approx. 900 mm A-axis: 270° C-axis: 540° Speed: X- / Y- / Z-axis: 60 m/min. A- / B-axis: 10,000°/min. Acceleration: X- / Y- / Z-axis: 3 m/sec² Cube dimensions (working area): X-axis: 2,000 mm Y-axis: 1,000 mm Z-axis: 500 mm Working area (cube dimensions) with a total tool length of 160 mm and a tool diameter of 160 mm. Table design: 1 x steel frame rotary table with dimensions: 1,000 x 2,000 mm. Max. table rotation time: 3 sec. Rotary table with center partition. While one side is being machined, the second side can be loaded or unloaded. 8 units of zero-point clamping systems, 4 units per table side, for quick fixture changes. Vacuum supply: 2 vacuum clamping circuits per table, with vacuum distribution unit, quick-release couplings on the table. 2 vacuum pumps, 1 per table, frequency-controlled, suction capacity approx. 100 m³/h, vacuum tank 250 liters, including frame. Universal head for 5-axis milling with a 90° head and tool change milling spindle C-axis (rotary axis) 540° (+/- 270°) A-axis (swivel axis) 270° (+/- 135°) Speed: 10,000°/min 1 milling spindle HSD Asynchronous motor, water-cooled for tool holder HSK-F63 max. power 12 kW (S1) / 15 kW (S6) max. speed 24,000 1/min Torque support with air supply for angle heads. 1 compressed air nozzle on the milling head, controllable via M-function. Tool changer: 1 carousel tool magazine with 12 positions, mounted on the side. 6 x positions: for tools up to 60 mm in diameter 5 x positions for angle heads and probing system 1 x position for saw blade up to Ø 350 mm. Control system: 1 machine control system Siemens SINUMERIK 840D SL User memory: CNC 3 MB Control panel with 15" display with graphic color LCD, foil keyboard, and mouse. Drives: Rack and pinion drives in the X and Y axes, ball screw drive in the Z axis, A/C axis with hollow shaft drive. Safety: 1 soundproof cabin, with maintenance door, including interior lighting. 1 automatic high-speed roller shutter door. Accessories: Chip guide plates inside the protective enclosure. Extraction system in the working area, to be connected to the extraction system. Receiver for 3D measuring probe. Tool breakage monitoring system. Both machines are assembled and ready for operation and can be inspected. An extraction system from Keller Absaugtechnik, including complete piping, is available. This extraction system was designed for 2 x MAKA DC 7 and is also for sale. We would be happy to prepare an offer for you!

Condition: excellent (used), For sale: CNC rotary table from the renowned brand Fadal Engineering (USA), model VH65. Professional 4th axis designed for machining centers, especially Fadal VMC, but integration with other CNC machines is also possible using the appropriate controller. Technical specifications: • Model: VH65 • Table diameter: 165 mm (6.5”) • Gear ratio: 90:1 • Pneumatic brake (M60 ON / M61 OFF) • Industrial multipin connector • Serial no.: 4630298 Condition: used, mechanically functional, normal signs of operation. Solid and heavy construction – ideal for precise 4-axis machining. Bwedpfx Aiow R St Nehop

Condition: ready for operation (used), Four identical Nagel + Hermann transfer and placement machines for transfer motifs (rhinestone, hotfix or similar) are available. Colors: 6, shapes: 2, production capacity: 5000elements/h, machine dimensions X/Y/Z: approx. 2000mm/1050mm/1750mm, weight: approx. 320kg. Including PC, CAD software, 12x conveyor plates as well as various spare parts and tools. Documentation available. An on-site inspection is possible. Bsdpfxszdkp Uj Aihewp

Condition: ready for operation (used), Three identical Nagel + Hermann transfer and placement machines for transfer motifs (rhinestone, hotfix or similar) are available. Production capacity: 7000elements/h, round element diameter: 2mm/3mm/4mm/5mm/6mm/8mm. Including laptop, CAD software, feed plate, various tools and spare parts. Documentation available. An on-site inspection is possible. Bwsdpfx Aiezdkpzjhjp

Condition: ready for operation (used), Two identical Nagel + Hermann transfer and setting machines for transfer motifs (rhinestone, hotfix, or similar) are available. Colors: 6, shapes: 2, production output (2-color): 8000elements/h, feed bowl diameter: 200mm. Machine dimensions X/Y/Z: approx. 2450mm/1100mm/1800mm, weight: approx. 400kg. Including PC, CAD program, 8x feed plates, 22 feed bowls, 4 rotary tables, as well as various spare parts and tools. Documentation available. An on-site inspection is possible. Bwsdpfx Aiozdkp Ijhsp

Condition: used, TECHNICAL DETAILS - Number of axes : 27 - Number of posts : 12 - Number of machining stations : 9 - Indexing time : 2 [sec] MACHINING UNIT - Designation : UV151-3 - Number of units : 1 - Travels on X/Y/Z axes : 110 / 150 /100 [mm] - Rapid traverse rate : 6500 [mm/min] - Resolution : 0.001 [mm] MACHINING UNIT - Designation : UV50-3 - Number of units : 8 - Travels on X/Y/Z axes : 40 / 120/ 100 [mm] - Rapid traverse rate : 6500 [mm/min] - Resolution : 0.001 [mm] SPINDLES - Spindle type : Electrobroche Ø38 * Number of spindles : 14 * Tool holder type : ISO10 * Spindle speeds : 18 000 [rpm] * Spindle power : 0.25 [kW] - Spindle type : Electrobroche Ø38 * Number of spindles : 4 * Tool holder type : ISO10 * Spindle speeds : 9000 [rpm] * Spindle power : 0.25 [kW] * Spindle type : Electrobroche Ø120 - Number of spindles : 1 - Tool holder type : HSK40 * Spindle speeds : 8710 [rpm] * Spindle power : 3.8 [kW] * Spindle type : Electrobroche Ø38 - Number of spindles : 2 - Tool holder type : ISO10 * Spindle speeds : 9000 [rpm] * Spindle power : 0.25 [kW] POWER SUPPLY - Supply voltage : 400 [V] - Total installed power : 10 [kW] WEIGHT & DIMENSIONS - Machine floor space : 4600 x 3600 [mm] - Machine height : 3200 [mm] - Machine weight : 13500 [kg] - Equipment EQUIPMENT - CNC : Siemens - Cooling unit - Coolant tank * with high-pressure pump - Chips conveyor Bjdow Huhcspfx Aihewp - Oil mist extractor : ELBARON RON/A 120 - Loader - Fire-fighting device - Fitting

Condition: used, TECHNICAL DETAILS - Number of axes : 27 - Number of posts : 12 - Number of machining stations : 9 - Indexing time : 2 [sec] MACHINING UNIT - Designation : UV151-3 - Number of units : 1 - Travels on X/Y/Z axes : 110 / 150 / 135 [mm] - Rapid traverse rate : 6500 [mm/min] - Resolution : 0.001 [mm] MACHINING UNIT - Designation : UV50-3 - Number of units : 8 - Travels on X/Y/Z axes : 40 / 120 / 100 [mm] - Rapid traverse rate : 6500 [mm/min] - Resolution : 0.001 [mm] SPINDLES - Spindle type : Electrospindle Ø38 * Number of spindles : 14 * Tool holder type : ISO10 * Spindle speeds : 18.000 [rpm] * Spindle power : 0.25 [kW] - Spindle type : Electrospindle Ø38 * Number of spindles : 4 * Tool holder type : ISO10 * Spindle speeds : 9.000 [rpm] * Spindle power : 0.25 [kW] - Spindle type : Electrospindle Ø120 * Number of spindles : 1 * Tool holder type : HSK40 * Spindle speeds : 8.710 [rpm] * Spindle power : 3.8 [kW] - Spindle type : Electrospindle with gear reducer Ø38 Bwedpfx Aev Rgy Hsihsp * Number of spindles : 2 * Tool holder type : ISO10 * Spindle speeds : 9.000 [rpm] * Spindle power : 0.25 [kW] POWER SUPPLY - Supply voltage : 400 [V] - Total installed power : 10 [kW] WEIGHT & DIMENSIONS - Machine floor space : 4600 x 3600 [mm] - Machine height : 3200 [mm] - Machine weight : 13500 [kg] EQUIPMENT - CNC : Siemens - Cooling unit - Coolant tank * with high-pressure pump - Chips conveyor - Oil mist extractor : ELBARON RON/A 120

Condition: used, TECHNICAL DETAILS - Number of axes : 27 - Number of posts : 12 - Number of machining stations : 9 - Indexing time : 2 [sec] MACHINING UNIT - Designation : UV151-3 - Number of units : 1 - Travels on X/Y/Z axes : 110 / 150 / 135 [mm] - Rapid traverse rate : 6500 [mm/min] - Resolution : 0.001 [mm] MACHINING UNIT - Designation : UV50-3 - Number of units : 8 - Travels on X/Y/Z axes : 40 / 120 / 100 [mm] - Rapid traverse rate : 6500 [mm/min] - Resolution : 0.001 [mm] SPINDLES - Spindle type : Electrospindle Ø38 * Number of spindles : 14 * Tool holder type : ISO10 * Spindle speeds : 18.000 [rpm] * Spindle power : 0.25 [kW] - Spindle type : Electrospindle Ø38 * Number of spindles : 4 * Tool holder type : ISO10 * Spindle speeds : 9.000 [rpm] * Spindle power : 0.25 [kW] - Spindle type : Electrospindle Ø120 * Number of spindles : 1 Bwedpfx Ajv Rgyysihop * Tool holder type : HSK40 * Spindle speeds : 8.710 [rpm] * Spindle power : 3.8 [kW] - Spindle type : Electrospindle with gear reducer Ø38 * Number of spindles : 2 * Tool holder type : ISO10 * Spindle speeds : 9.000 [rpm] * Spindle power : 0.25 [kW] POWER SUPPLY - Supply voltage : 400 [V] - Total installed power : 10 [kW] WEIGHT & DIMENSIONS - Machine floor space : 4600 x 3600 [mm] - Machine height : 3200 [mm] - Machine weight : 13500 [kg] EQUIPMENT - CNC : Siemens - Cooling unit - Coolant tank * with high-pressure pump - Chips conveyor - Oil mist extractor : ELBARON RON/A 120

Condition: used, TECHNICAL DETAILS - Number of axes : 48 - Number of posts : 16 - Number of units : - Number of possible horizontal units : 16 - Number of possible vertical units : 7 - Max. diameter : 45 [mm] - Max. part width : 150 [mm] - Basis unit GM50/150 : * Stroke Z : 150 [mm] * Spindle power : 5 [kW] * Spindle speed : 0 - 8000 [Rpm] Bedpfxou N Ivqs Aihowp - Slide X/Y : * Strokes X : +/- 40 [mm] * Strokes Y : +/- 20 [mm] - Dimensions : 14000 x 4800 x 3000 [mm] - Weight : 13 [t] - Number of hours : 4283 [h] EQUIPMENT - Control CNC Bosch Rexroth INDRAMOTION MTX-L85 - Post 1 : * sawing unit 52/100 3 axes - Post 2 : * slide 50/150 (manual adjustment) ref. 22.10.002-1 * unit 50/150 ref 22.42.001-6 (1 axis) * coolant through spindle - Post 3 : * slide 50/150 (manual adjustment) ref. 22.10.002-1 * unit 50/150 ref 22.42.001-6 (1 axis) * coolant through spindle - Post 4 : * slide 50/150 (manual adjustment) ref. 22.10.002-1 * unit 50/150 ref 22.42.001-6 (1 axis) * coolant through spindle - Post 5 : * slide CNC 50/150 ref 22.10.001-4 (2 axes) * unit CNC 50/150 ref 22.42.001-6 (with CNC turning function) * coolant through spindle - Post 6 : * slide CNC 50/150 ref 22.10.001-4 (2 axes) * unit CNC 50/150 ref 22.42.001-6 (with CNC turning function) * coolant through spindle - Post 7 : * slide 50/150 manual adjustment ref 22.10.002.1 * unit recessing ref 22.42.041.1 - Post 8 : * slide CNC 50/150 ref 22.10.001.4 (2001) * unit CNC 50/150 ref 22.42.001.6 (with CNC turning function) - Post 9 : * slide CNC 50/150 ref 22.10.001.4 * recessing unit ref 22.42.039.2 - Post 10 : * slide 50/150 manual adjustment ref 22.10.002.1 * recessing unit ref 22.42.039.8 - Post 11 : * slide CNC 50/150 ref 22.10.001.4 * unit 50/150 ref 22.42.001.6 (CNC turning function) - Post 12 : * slide 50/150 ref 22.10.002.1 * recessing unit ref 22.42.041.1 - Post 13 : * slide CNC 50/150 ref 22.10.001.4 * recessing unit ref 22.42.041.1 - Post 14 : * slide CNC 50/150 ref 22.10.001.4 * unit CNC 50/150 ref 22.42.001.6 (turning function) - Post 15 : * slide CNC 50/150 ref 22.10.001.4 * unit CNC 50/150 ref 22.42.001.6 (turning function) * coolant through spindle - Post 16 : * slide CNC 50/150 ref 22.10.001.4 * unit CNC 50/150 ref 22.42.001.6 (turning function) * coolant through spindle - Bar feeder length 4 m - Coolant tank KNOLL (2000 Liters) with HP pump 60 [bars] - Chips conveyor

Condition: used, TECHNICAL DETAILS - Posts number : 16 - Indexing time : 0,7 [s] - Max. bar diameter : 32 [mm] - Clamping type : collet VB 32 - Max. part length : 150 [mm] - Max. number of horizontal units : 16 - Max. number of vertical units : 24 - Max. number of all units : 24 - Electrical supply : 400 [V] - Installed power : 40 [kW] - Dimensions : 9,8 x 4 x 2,9 [m] - Weight : 6 500 [kg] EQUIPMENT - CNC SIEMENS Sinumerik 805 Bwedpfxjuhbwis Aihep - Bar feeder HYDROMAT - 2 turning units CNC 2 axes - Band part conveyor - Chip conveyor - Lubricating tank - Filtration