Used Kasto Kastowa C 7 for sale (126)

Condition: used, Year of construction: 2001, Technical details: saw blade diameter: 250/285 mm cutting diameter: 50-70 mm total power requirement: 5,5 kW weight of the machine ca.: 1 t Blsdpfewvbk Ajx Adqsk Saw type: circular saws Cutting direction: straight cut Automation: automatic Material type: structural steels, stainless steels, tool steels Material width: 60 mm Material height: 70 mm *

Condition: refurbished (used), Year of construction: 2024, Overhauled: 2024 Saw band 250-285 mm Motor power 5.5 KW Cutting speed 35-160 m/min Working range square max.: 15 - 60 mm Working range round max.: 15 - 70 mm Saw feed 2 - 100 mm/s infinitely adjustable Cutting length 5-250 mm Feed speed max. 1000 mm/s Weight (saw)approx.: 1500 kg (magazine)approx.: 800 kg Dimensions LxWxH (saw)approx.: 1100mm x 1600mm x 2300mm (magazine)approx.: 7500mm x 1400mm x 1600mm The machine is suitable for mass cutting of steel due to its equipment and construction and is the predecessor of the KASTOwa C7 and KASTOspeed C9. The machine will be in mint condition after a general overhaul (retrofit), which is guaranteed by our company. The machine will be generally overhauled in our company at the customer's request. Among other things, the following points will be renewed: - New PLC control Siemens S7 - Conversion to Siemens HMI - Conversion to fully electronic section length selection (optional) - New electrical components - New pneumatic lines - Overhaul or replacement of all pneumatic components - New hydraulic lines - Overhaul or replacement of all hydraulic components - Overhaul of Menzel minimum lubrication system - Replacement of general wear parts - Overhaul of the loading magazine - Extension of the safety concept The machine also has: - a slide-off magazine for 6m bars - Hydraulic material feed unit Warranty: Bedeuizlcjpfx Adqolk Unless otherwise agreed, we provide a 6-month guarantee on all parts overhauled or replaced by us. Working time and wearing parts are excluded from the guarantee. Optional: - Conversion to spindle extraction - Conversion to trapezoidal spindle stop manual 0-800mm - Conversion to fully electronic ball screw stop 0-800mm - Conversion of main saw drive to 18 KW - Delivery and installation on your premises - Training of your employees

Condition: excellent (used), Year of construction: 2005, saw blade diameter 360 / 400 / 425 mm cutting diameter 10 - 140 mm cutting speed 8 - 150 m/min required cooling water max. 40 l/min height of material-table 950 mm max. travel between columns 680 mm control Siemens Simatic Bodpfjvzt Eqjx Adqslk total power requirement 28 kW weight of the machine ca. 4,2 t dimensions of the machine ca. 2,8 x 1,8 x 2,2 m

Condition: ready for operation (used), Year of construction: 2008, Circular Metal Saw manufactured in 2008. This KASTO KASTOspeed C 9 is designed for sawing steel and non-ferrous metals, featuring a cutting range of round ø15-90 mm or 15x15-80x80. It includes a powerful 11 kW saw unit drive motor, enabling cutting speeds of 50-700 m/min. If you are looking to get high-quality sawing capabilities, consider the KASTO KASTOspeed C 9 machine we have for sale. Contact us for further details. • For sawing: Steel and non-ferrous metals • Condition: Test machine, used very little • Cutting direction: 90° • Saw blade diameters: 250 / 285 / 315 mm • Cutting range: round Ø15–90 mm; square 15×15–80×80 mm • Saw unit drive motor: 11 kW (optional equipment); enables cutting speeds of 50–700 m/min • Lubrication: 2 separate and independently selectable minimum-quantity lubrication tanks Additional equipment • Angled magazine, loading length 6000 mm • Material cart with drawbar • Gantry crane, maximum load 1000 kg • Oil mist extraction system • Chip conveyor • Tilting chip container with casters Bodpfxozha R Nj Adqelk

Condition: used, Year of construction: 2008, functionality: fully functional, saw blade diameter: 460 mm, cutting range round steel at 90°: 152 mm, Circular saw – automatic (used) Manufacturer: KASTO Model: VARIOSPEED C15 Year of manufacture: approx. 2008 Control: CNC control KASTO TECHNICAL DATA Saw blade diameter max. 460 mm Cutting range, round 152 mm Cutting range, square 135 mm Saw blade feed, continuously adjustable from 8 mm/min Saw blade feed, continuously adjustable up to 1000 mm/min Cutting speed 150 m/min Hydraulic clamping device: yes ELECTRICAL CONNECTION DATA Power consumption (total) 28 kW Connection voltage 400 V Mains frequency 50 Hz Bledpfozd A Rqjx Adqek DIMENSIONS / WEIGHTS Space requirement – left/right – 10600 mm Space requirement – front/rear – 4500 mm Overall height 2340 mm Total weight approx. 3900 kg Very good condition Serviced twice a year by the manufacturer Kasto

Condition: good (used), Year of construction: 2008, functionality: fully functional, saw blade diameter: 460 mm, cutting range round steel at 90°: 152 mm, total height: 2,340 mm, total width: 4,500 mm, cutting speed: 150 mm/min, overall weight: 3,900 kg, Circular saw – automatic (used) Bodozd A Ntepfx Adqslk Manufacturer: KASTO Model: VARIOSPEED C15 Year of manufacture: approx. 2008 Control: CNC control KASTO TECHNICAL DATA Saw blade diameter max.: 460 mm Cutting range, round: 152 mm Cutting range, square: 135 mm Saw blade feed, continuously adjustable from: 8 mm/min Saw blade feed, continuously adjustable up to: 1000 mm/min Cutting speed: 150 m/min Hydraulic clamping device: yes ELECTRICAL CONNECTION DATA Power consumption (total): 28 kW Connection voltage: 400 V Mains frequency: 50 Hz DIMENSIONS / WEIGHTS Space requirement – left/right: 10600 mm Space requirement – front/rear: 4500 mm Overall height: 2340 mm Total weight approx.: 3900 kg Very good condition Serviced twice a year by the manufacturer Kasto Includes robot and other expensive machine accessories

Condition: used, Year of construction: 2016, saw blade diameter 360 mm Bljdpfsv Nq Rmex Adqjk cutting width at round material 15 - 100 mm cutting width at rectangle material 15 - 80 mm cutting speed 17 - 175 m/min Control Easy Control KASTO total power requirement 21 kW weight of the machine ca. 3,4 t dimensions of the machine ca. 3,3 x 1,6 x 2,2 m The saw blade drive gearbox was renewed in 03/2023 by the manufacturer Material feed Material discharge Chip conveyor

Condition: used, Year of construction: 2004, saw blade diameter 360 / 425 / 460 mm cutting diameter 10 - 140 mm cutting speed 25 - 160 m/min total power requirement 35 kW weight of the machine ca. 4,2 t dimensions of the machine ca. 2,8 x 1,8 x 2,2 m Bsdsv Nq Rtspfx Adqslk

Condition: used, Heavy-duty, high-performance automatic band saw with a horizontally, parallel-traveling saw band, built 2005, for cutting round, square and flat material as well as tubes and profiles in all grades — especially tool steels and hard-to-machine materials (titanium, Hastelloy, Inconel, etc.). Cutting range: round ø430 mm, square/flat H×W 430×430 mm, clamping range 0–430 mm. Saw unit in steel-mineral-cast composite construction with KASTO TrumGuides vibration damping. Saw drive 15.0 kW (14.0 kW at the wheel), connected load 25.0 kW, stepless cutting speed 30–300 m/min, saw feed 0.5–300 mm/min. Automatic NC material feed via ball-screw drive, hydraulic clamping vises on both sides, hydraulically actuated and electronically monitored band tension, self-adjusting chip removal brush, automatic cutting-gap widening and automatic zero-positioning of the first cut. Fitted with a plate belt conveyor and KASTO EasyControl. Delivered WITHOUT infeed magazine — sold without the existing chain magazine. Bedpezpb Eqsfx Adqjlk

Condition: used, Year of construction: 1996, cutting diameter 460 mm saw band length 8350 x 41 x 1,3 mm mm cutting width 1660 mm total power requirement 30 kW weight of the machine ca. 21.900 kg KASTO BBS 460/1660 2 identical machines (same photos; the other machine was built in 1998) Manufacturer: KASTO Maschinenbau GmbH & Co. KG Address: Industriestr. 14, D-77856 Achern-Gamshurst, Germany Type: BBS 460/1660 (Block Band Saw / Horizontal Bandsaw) Series: 101 Machine No.: 63191010041 Year of Manufacture: 1996 DIMENSIONS & WEIGHT Weight: 21.900 kg (data card) / approx. 17,700 kg (foundation plan) Material Support Height: 1,550 mm Machine Footprint (L x W x H): approx. 1.24 × 3.28 × 3.49 m Minimum Installation Space (with accessories/options): approx. 20.19 × 10.67 × 3.95 m Cutting Range (at 90°) Bledpfx Adszmy S Roqok Round Material: Ø 460 mm Flat / Block Material: 1,660 × 460 mm SAW BLADE Standard Sizes: 8,350 × 54 × 1.3 mm or 8,350 × 41 × 1.3 mm Alternative (per data card): 8,350 × 54 × 1.3 mm Kerf Width (Set): approx. 2.4 mm Band Wheels: 3 × Ø 350 mm Recommended Quality: Super Bi-Metal Saw Blades (M42) for mild steels, high-alloy tool steels, and stainless steels For extremely hard materials: Carbide-tipped blades PERFORMANCE DATA Band Speed: infinitely variable 14 – 75 m/min Feed Rate (Step Feed): infinitely variable 0.7 – 220 m/min Electrical Connection: 400 V / 50 Hz / 30 kW (total connected load) Coolant Capacity: 6.5 l Noise Level: 73 dB(A) Function Manufacturer Type Power (kW) / Current (A) Speed (rpm) ----- Saw Motor Sieber VM6-1054/750/4 7.5 kW / 15.6 A 1500 Hydraulic Motor BauKnecht DT90-S4F 1.1 kW / 3.0 A 1500 Hydraulic Power Unit Rexroth UL 205S2016294/1 2.2 kW / 5.6 A 1500 Roller Track Motor SEW KG 35 1.2/4.8 kW / 4.6/10 A 750/3000 Band Speed Motor SEW KE66 DT 80 N 612 0.12/0.48 kW / 0.69/1.32 A 750/3000 Rapid Traverse (Eilgang) SEW KE66 DT 80 N 612 0.12/0.48 kW / 0.69/1.32 A 750/3000 Adjustment Motor Sieber DE26.18 kW / 0.6 A 3000 Coolant Pump Brinkmann TS12/190-65 0.27 kW / 0.63 A 3000 Coolant Pump Brinkmann TB 100/270 0.24 kW / 0.44 A 3000 Chip Conveyor Pump Huber + Moser 693/8F 0.08 kW / 0.65 A 750 Chip Conveyor SEW SA 42 DT 71 DB 0.12 kW / 0.69 A 750

Condition: used, Year of construction: 1996, cutting diameter 460 mm saw band length 8350 x 41 x 1,3 mm mm cutting width 1660 mm total power requirement 30 kW weight of the machine ca. 21.900 kg KASTO BBS 460/1660 2 identical machines (same photos; the other machine was built in 1996) Manufacturer: KASTO Maschinenbau GmbH & Co. KG Address: Industriestr. 14, D-77856 Achern-Gamshurst, Germany Type: BBS 460/1660 (Block Band Saw / Horizontal Bandsaw) Series: 101 Machine No.: 6319 101 004 Year of Manufacture: 1996 DIMENSIONS & WEIGHT Weight: 21.900 kg (data card) / approx. 17,700 kg (foundation plan) Material Support Height: 1,550 mm Blsdpfozmy Sqex Adqok Machine Footprint (L x W x H): approx. 1.24 × 3.28 × 3.49 m Minimum Installation Space (with accessories/options): approx. 20.19 × 10.67 × 3.95 m Cutting Range (at 90°) Round Material: Ø 460 mm Flat / Block Material: 1,660 × 460 mm SAW BLADE Standard Sizes: 8,350 × 54 × 1.3 mm or 8,350 × 41 × 1.3 mm Alternative (per data card): 8,350 × 54 × 1.3 mm Kerf Width (Set): approx. 2.4 mm Band Wheels: 3 × Ø 350 mm Recommended Quality: Super Bi-Metal Saw Blades (M42) for mild steels, high-alloy tool steels, and stainless steels For extremely hard materials: Carbide-tipped blades PERFORMANCE DATA Band Speed: infinitely variable 14 – 75 m/min Feed Rate (Step Feed): infinitely variable 0.7 – 220 m/min Electrical Connection: 400 V / 50 Hz / 30 kW (total connected load) Coolant Capacity: 6.5 l Noise Level: 73 dB(A) Function Manufacturer Type Power (kW) / Current (A) Speed (rpm) ----- Saw Motor Sieber VM6-1054/750/4 7.5 kW / 15.6 A 1500 Hydraulic Motor BauKnecht DT90-S4F 1.1 kW / 3.0 A 1500 Hydraulic Power Unit Rexroth UL 205S2016294/1 2.2 kW / 5.6 A 1500 Roller Track Motor SEW KG 35 1.2/4.8 kW / 4.6/10 A 750/3000 Band Speed Motor SEW KE66 DT 80 N 612 0.12/0.48 kW / 0.69/1.32 A 750/3000 Rapid Traverse (Eilgang) SEW KE66 DT 80 N 612 0.12/0.48 kW / 0.69/1.32 A 750/3000 Adjustment Motor Sieber DE26.18 kW / 0.6 A 3000 Coolant Pump Brinkmann TS12/190-65 0.27 kW / 0.63 A 3000 Coolant Pump Brinkmann TB 100/270 0.24 kW / 0.44 A 3000 Chip Conveyor Pump Huber + Moser 693/8F 0.08 kW / 0.65 A 750 Chip Conveyor SEW SA 42 DT 71 DB 0.12 kW / 0.69 A 750

Condition: excellent (used), Year of construction: 2017, functionality: fully functional, Kasto KASTOwin pro AC 5.6 fully automatic band saw for metals (2017) Manufacturer: Kasto Type: KASTOwin pro AC 5.6 Year of manufacture: 2017 Condition: used, operational Operating hours: see photos. Scope of delivery: Bjdpjzl Tfhefx Adqslk - Documentation

Condition: used, Year of construction: 2005, Technical Data: Cutting capacity: 90° round: 260 mm 90° flat: 300 x 260 mm 90° square: 260 x 260 mm +45° round: 200 mm +45° flat: 200 x 240 mm +45° square: 200 x 200 mm +60° round: 165 mm +60° flat: 160 x 120 mm +60° square: 150 x 150 mm -45° round: 200 mm -45° flat: 200 x 240 mm -45° square: 200 x 200 mm Shortest residual piece length: 35 mm Total connected load: 2.0 kW Saw motor, frequency-controlled: 1.5 kW Bledpfxjx Irx Is Adqjk Infinitely variable cutting speed (frequency-controlled): 20 - 110 m/min Saw band dimensions: 2910 x 27 x 0.9 mm Dimensions and weight: Length, approx.: 1020 mm Width, approx.: 1830 mm Height, upper part lowered, approx.: 1460 mm Height, upper part fully raised: 1900 mm Material support height: 950 mm Total weight, approx.: 510 kg Features: - Infinitely variable cutting speed - Saw band guides made of carbide, replaceable - Hydraulic saw feed - Mechanical saw band tensioning - Machine light - Saw band cleaning via freely rotating, easily replaceable wire brush - Coolant supply via 1 coolant nozzle and 1 coolant hose, coolant tank capacity approx. 45 l, pump capacity 16 l/min - Minimum quantity lubrication - Infeed roller conveyor (1000 mm) and outfeed roller conveyor (2000 mm) with scale and length stop

Condition: good (used), Hacksaw, hacksaw machine -Hoop saw: electric, with coolant system -Type: unfortunately no type designation -Power: 0.55 / 0.75 kW -Max. cutting height: approx. 145 mm -Max. cutting width: approx. 180 mm -Saw blade: Length approx. 325 mm -Machine dimensions: 800/700/H1520 mm Blodpfx Adsg R Tffoqek -Weight: 224 kg

Condition: good (used), Year of construction: 2001, Cutting 90°: 330 Cutting flat 90°: 330 x 330mm Cutting speed Vario:12 - 120 Circle blade size: 6830 x 41 x 1,3mm Power: 7.5kW Bledpeu R R Acsfx Adqek Length: 4600mm Width: 2150mm Height: 2310mm Weight: 4300kg Please Note: The information on this page has been obtained to the best of our ability and belief, and from the manufacturers where possible. It is given in good faith, but its accuracy can not be guaranteed. Accordingly, it will not form a representation or constitute contractual terms. We advise you to check any vital details!

Condition: good (used), Year of construction: 2001, Manufacturer: KASTO Type: KASTOtec A4 Year of construction: 2001 Specifications: Metric Metric US Standard Sawing capacity round 90 430 Sawing capacity flat 90 430 x 430 mm Feed range 0 - 600 mm Multi-feed range 0 - 9999 mm Min, saw length 35 mm Max. Sawing speed 12 - 120 Saw blade dimensions 6830 x 41 x 1.3 mm Saw power 7.5 kW Dimensions (estimate) length 4800 mm width 2200 mm Bsdou R R Avepfx Adqslk Height 2200 mm weight 5200 kg Please note: The information on this page is given in good faith and to the best of our knowledge, and where possible, has been obtained from the manufacturer, but accuracy cannot be guaranteed. Accordingly, it does not constitute a representation or contract and we recommend that you check all relevant details.

Condition: excellent (used), Year of construction: 2010, Kasto Functional A horizontal band saw Year: 2010 Technical details: max cutting diameter 260 mm saw band length 3830 x 29 x 0,9 mm cutting speed 19-100 m/min total power requirement 2,2 kW weight of the machine ca. 860 kg dimensions of the machine ca. 1550 x 1700 x 1480 mm vice opening 300 mm angle cutting left/rigt: 45degree/60degree Bedpfjy Urz Nex Adqolk Kasto Compact Control - colour touchpad screen Frequency controlled saw drive Infinitely adjustable cutting feed Hydraulic clamping vice Material feed Coolant system Speed control c/w roller conveyor, saw blades, documentations

Year of construction: 2020, condition: as good as new (ex-display), Bandsaw machine Manufacturer: KASTO Model: micut P 2.6 Year of manufacture: 2020 - Demonstration machine Machine no.: 6151 101 006 Bodpfx Adedur E Aeqolk With warranty Standard equipment includes: - Stepless cutting speed 20 - 110 m/min - Horizontal clamping device, manual tensioning - Stepless miter adjustment (-45° to +60°) - Stepless saw blade arm adjustment - Adjustable saw feed via self-weight - Cutting guide as material support - Automatic shutdown after cut completion - Coolant system - Operating manual With the following options: - Drip oiler

Condition: excellent (used), Frietsch SAWMILL MACHINERY Buying and selling KASTO sawing machines Dear Sir or Madam, Bjdpsfh Hukefx Adqelk We buy, sell, overhaul, repair, and repaint KASTO sawing machines. We have over 40 years of experience with KASTO sawing machines and have specialized in overhauling these machines. We can also handle KASTO control systems! The machines are overhauled by trained personnel according to KASTO factory standards. We also source KASTO sawing machines according to your specifications for machine overhauls. Excellent price-performance ratio thanks to professional machine overhauls.

Condition: excellent (used), Year of construction: 2003, functionality: fully functional, KASTOtec AC 4 Cutting Capacity Round: 430 mm Cutting Capacity Square H x W: 430 x 430 mm Cutting Capacity Flat H x W: 430 x 430 mm Clamping Range: 0 – 430 mm Smallest Workpiece Dimension: 10 x 10 mm Minimum Cut-off Length: 6 mm Shortest Remainder Length in Automatic Operation (only for geometrically flawless surfaces): 35 mm Shortest Remainder Length in Single Cut: 10 mm Dimensions and Weights: Length approx.: 2,140 mm Width incl. chip conveyor: 4,610 mm Height (saw frame lowered) approx.: 2,195 mm Height (saw frame at highest position) approx.: 2,410 mm Material Support Height: 700 mm Total Weight: 4,300 kg Year of Manufacture: 2003 Performance Data: Blsdpfey Dckmsx Adqek Total Connected Load: 25 kW Saw Motor Power: 15 kW Drive Power at Flywheel: 14 kW Cutting Speed—stepless, 50/60 Hz version: 12 - 120 m/min Automatic Material Feed Length Single: 600 mm Saw Blade Dimensions: 6,830 x 41 x 1.3 mm Coolant Tank Capacity: 150 l KASTOtec AC 4 Fully hydraulic high-performance band saw in heavy-duty design Suitable for cutting round, square, flat material as well as tubes and profiles in all grades, especially for tool steels and difficult-to-machine materials such as titanium, Hastelloy, Inconel, etc. Machine Base Torsion-resistant welded construction Saw Unit of steel-mineral composite construction Saw Unit Guidance High-performance sawing technology requires backlash-free and low-maintenance guidance systems. Two vertical square guide columns, one linear guide unit with backlash-free set carriages, as well as two preloaded and adjustable rollers on a guide rail ensure high rigidity and cutting accuracy. Greater machining performance, shorter cutting times, higher blade life, and maintenance-free guide systems with high availability characterize the new KASTOtec. Saw Blade Guidance Side guides by hydraulically preloaded carbide slide guides with quick lift feature for fast blade changes. Back guide by oscillating carbide slide guides. Automatic adjustment of the movable blade guide according to the width of the material to be cut. Material Lift Device After cutting in automatic cycle, the workpiece is moved approx. 2 mm away from the blade on the feed side using the material lift device while clamped (increases blade life). Options for the Machine - Carbide package - Coolant monitoring - Blade tracking - Speed monitoring - Machine lamp - Roller conveyor - CNC control - Special chip conveyor - Carbide package Discharge Roller Conveyor for the KASTOtec AC 4 available in stock, dimensions: 1200 mm long, 500 mm support width, 6 transport rollers

Year of construction: 1988, condition: used, machine/vehicle number: 103.071.3156.78192, disk of circular saw-Ø: 400 u. 425 mm cutting area at 90° round: 130 mm cutting area at 90° square: 120 x 120 mm cutting area in mitre at 45° round: 130 mm cutting area in mitre at 45° square: 110 x 110 mm cutting speeds: 11 u. 22 m/min Bledpfx Ajz N Amedqjk forward feed speeds: 670 mm/min cutting length: m. automat. Vorschub bis 1200 mm electrical connection: 380 V, ca. 4 kVA V sawing drive: 1,6/2,5 kW space needed: 1800 x 3800 x 2000 mm weight: ca. 1800 kg

Condition: used, Year of construction: 1988, 370 mm rund ja möglich Bljdpfxsupmwre Adqok

Condition: used, Year of construction: 2011, functionality: fully functional, machine/vehicle number: 3515 104 114, saw blade diameter: 350 mm, cutting range round steel at 45°: 100 mm, cutting range round steel at 90°: 100 mm, total length: 800 mm, total width: 1,250 mm, overall weight: 350 kg, cutting range square steel at 90°: 90 mm, The KASTOdisc U 10 is a robust semi-automatic vertical cold circular saw, suitable for precise metal cutting in workshops and medium series. Featuring two speeds and an adjustable feeder, it offers flexibility and high-quality cuts, while the pneumatic clamp stabilizes the material. Blsdpewxcuzefx Adqsk

Year of construction: 2004, condition: good (used), A used, well-maintained double miter cold circular sawing machine from KASTO, model: “KASTOdisc A10” - Fully automatic operation - Single cut - Hydraulic clamping cylinders - Central lubrication for saw guides - Coolant system - Documentation Saw blade diameter 350 mm Cutting range: Round 90°/45° 100/100 mm Bjdpekfvhkefx Adqelk Square 90°/45° 100x100/100x100 mm Rectangle 90°/45° 170x100/130x100 Shortest remaining piece length in single cut at 90°: 30 mm Shortest remaining piece length in automatic operation at 90°: 260 mm Working height 950 mm Dimensions (W x D x H) 1530x1348x1890 mm Weight 980 kg Further technical data can be found in the PDF document. Technical data and dimensions: Subject to change.

Condition: good (used), Year of construction: 2003, Manufacturer: KASTO | Model: Funktional A | Serial Number: 6420 102 076 | Year of Manufacture: 2003 | Motor Power: 2.5 kW | Automatic metal band saw | Electric main drive | Hydraulic clamping and feed system | Integrated material feed with roller conveyor | Roller conveyors on both sides | Hydraulic material vise | Saw band guide with coolant supply | Control panel with controls and emergency stop | Suitable for bar and profile material | Dimensions: approx. 1700 mm x 1550 mm x 3600 mm (W x H x L) | approx. 890 kg | The stated dimensions are approximate. All other information without guarantee.| Grey | Steel Bodpsyicg Isfx Adqslk