Used Bed-Type Cnc Milling Machine for sale (89,314)

Condition: used, Year of construction: 1980, functionality: limited functionality, machine/vehicle number: 4119, travel distance X-axis: 1,450 mm, travel distance Y-axis: 365 mm, travel distance Z-axis: 415 mm, total width: 3,400 mm, total length: 4,200 mm, overall weight: 3,500 kg, Last major overhaul in 2006 Swiveling spindle head, 360° Control: Digital display Clamping area: 1800 x 400 mm Table load: 1000 kg Travel in the longitudinal direction: 1450 mm Gsdpfx Aez Nfbzongouh Travel in the transverse direction: 365 mm Travel in the vertical direction: 415 mm Spindle connection: SK40 Spindle speed: 31.5-45-63-90-125-180-250-355-500-710-1000-1400 rpm Feed rate in the longitudinal direction: 8-1200 mm/min Feed rate in the transverse direction: 8-1200 mm/min Feed rate in the vertical direction: 4-600 mm/min Spindle drive: 7.5 kW Feed motor: 3.2 kW Coolant pump: 0.18 kW Hydraulic system: 0.37 kW Total connected load: 12 kVA Weight, approx.: 3500 kg Space requirement, approx. (L x W): 4200 x 3400 mm Technical data subject to change without notice. Errors and prior sale excepted.

Year of construction: 1975, condition: ready for operation (used), travel distance X-axis: 8,000 mm, travel distance Y-axis: 950 mm, travel distance Z-axis: 1,150 mm, overall weight: 20,000 kg, spindle motor power: 11,000 W, number of axes: 3, General Data Machine weight 20000 kg Main Drive Number of axis 3 Spindle motor power 11 kW Tool taper ISO 50 Movement X-Axis Movement 8000 mm Z-Axis Movement 1150 mm Y-Axis Movement 950 mm This 3-axis Butler CS10 Bed Type Milling Machine was manufactured in 1975. It features a large 10,000 mm table length, 1030 mm table width, and a robust ISO 50 spindle taper. The main motor power is 11 kW, ensuring heavy-duty machining capability. It also includes original Elgamill guides for precise column travel. Consider the opportunity to buy this Butler CS10 Bed Type Milling Machine. Contact us for more information about this machine. Application Types Gedox D Dq Eepfx Angsuh Milling

Condition: like new (used), Year of construction: 2015, functionality: fully functional, travel distance X-axis: 3,000 mm, travel distance Y-axis: 1,200 mm, travel distance Z-axis: 1,500 mm, rapid traverse X-axis: 20,000 m/min, rapid traverse Y-axis: 20,000 m/min, rapid traverse Z-axis: 20,000 m/min, position of the milling head: 0.001, spindle speed (max.): 3,500 rpm, table width: 1,500 mm, table load: 10,000 kg, table length: 1,500 mm, type of input current: three-phase, workpiece weight (max.): 10,000 kg, overall weight: 26,000 kg, input voltage: 400 V, LAGUN GORATU GTM 3 MILLING MACHINE (TYPE T) TECHNICAL SPECIFICATIONS Gedpfx Anjy T Sffjgouh Brand: Lagun Model: GTM3 Year: 2016 CNC: Heidenhain iTNC 530 Table: 1500 x 1500 mm X: 3000 mm Y: 1200 mm Z: 1500 mm V (Column cross travel: 1000 mm Automatic milling head - ISO 50 Spindle speed: 4,000 rpm Rotary table (capacity 10 tons) Internal coolant system: 40 Bar Spindle power: 28/34.5 Kw Coolant filter PRICE AND FURTHER INFORMATION AVAILABLE UPON REQUEST (CNC, SIEMENS, HASS, LAGUN, FAGOR, CINCINNATI, HEIDENHAIN, MACHINING, PINACHO, MORISEIKI, MILLING MACHINE, LATHE, GRINDER, BORING MACHINE, PRESS, LASER, SHEAR, PRESS BRAKE)

Condition: like new (used), Year of construction: 2007, functionality: fully functional, travel distance X-axis: 7,000 mm, travel distance Y-axis: 1,210 mm, travel distance Z-axis: 1,850 mm, Manufacturer: FPT Year: 2007 CNC Control: HEIDENHAIN Axis Travels X-axis: 7,000 mm Y-axis: 1,210 mm Z-axis: 1,850 mm Milling Head / Rotary Axes A-axis: 270° B-axis: -180° / +180° C-axis: 360° Gsdpfx Anozznupsgeuh The machine is currently installed at our factory in Istanbul, Türkiye and is in working condition. The machine can be inspected under power at our facility. Further technical information, photos and videos can be provided upon request.

Condition: good (used), Mikron WF31D Precision Milling and Drilling Machine Machine with chip and splash guard enclosure Equipped with a Heidenhain TNC355 control system Technical Specifications The WF 31 D is a precision milling and drilling machine for series production and CNC training. Drive via an automatically switchable stepped gearbox and Poly-V belt. Vertical spindle can be extended by 90 mm; conversion from vertical to horizontal machining is possible. Ball screws with DC drives enable simultaneous feed movements. Guides are protected against dust, chips and coolant. Technical Data Manufacturer: Mikron Type WF31D Control system: Heidenhain TNC 355 Longitudinal movement (X): 560 mm Transverse movement (Y): 500 mm Vertical movement (Z): 400 mm Drive power: 3.3/4.0 kW Speed range: 40-4000 rpm Feed rate: 2-3000 mm/min Rapid traverse rate X/Y: 6000 mm/min, Z: 5000 mm/min Electrical Equipment Total installed rated power: 10.0 kW Installed useful power: 7.3 kW Operating voltage: 3 x 380 V - 50/60 Hz Protection class: IP 54 Max. permissible ambient temperature: +35 °C Relative humidity: 75 %. Dimensions and Weights Width: 2450 mm Length: 2800 mm Height: 2000 mm Net weight of the machine: approx. 2570 kg. Heidenhain TNC355 Operating Manual Heidenhain TNC355 Programming Examples Heidenhain TNC 355 Service Manual Gjdpfx Aewiucfsngouh More items - new and used - can be found in our shop! International shipping costs available upon request!

Condition: used, CNC universal tool milling machine DECKEL, type FP 4 ME - DEFECTIVE Machine No. 2205, Year of manufacture 1989 CNC path control: GRUNDIG Contur 3 - Control system does not boot up Travel ranges: X: 485 mm, Y: 385 mm, Z: 380 mm Table size: 800 x 460 mm Spindle mount: ISO 40 Spindle speed: 63 - 3150 rpm, 22 steps Feed rate range: 2 - 3000 mm/min, stepless Quill movement: Horizontal and Vertical Main spindle drive: 3.7 / 4.4 kW - Hydraulic tool clamping - Swiveling control panel - Electronic handwheel - Fixed angular table - Coolant system in the machine base Gjdpfxsz Ebvre Angeuh - Control cabinet located next to the machine, dimensions L x W x H: 800 x 750 x 1150 mm Space requirement L x W x H: 2000 x 2000 x 2000 mm Weight approx.: 2400 kg Good condition - control system does not boot up.

Condition: good (used), Year of construction: 2001, travel distance X-axis: 3,200 mm, travel distance Y-axis: 1,200 mm, travel distance Z-axis: 1,460 mm, table length: 3,800 mm, table width: 1,000 mm, table load: 30,000 kg, Chip conveyor Guodjxc Hh Depfx Angsh Double doors front side Chain Tool chnager 30 positions Central lubrication IKZ 16 Bar and 2,2 kW Flow 16L/Min Tool blocking power 1968 daN Full set books and 1e owner machine X-Axis: 3200mm Y-Axis: 1200mm Z-Axis: 1460mm Table Length: 3800mm Table Width: 1000mm Table load: 30000 Power on spindle: 41kW Spindle speeds: 3000Rpm Spindle Taper: 50ISO/Bt/Mk Feed rate X-Axis: 10000mm/min. Feed rate Y-Axis: 10000mm/min. Feed rate Z-Axis: 10000mm/min. Millinghead auto-index:2.5 x 2.5° Working hours: 10659H Length: 8820mm Width: 6250mm Height: 3910mm Weight: 33000kg 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: like new (used), Year of construction: 1996, Retrofitted: 2026 Numerical control: NUEVO/NEW HEIDENHAIN TNC-320 Gedpfx Aoyf Rr Tsngeuh Technical features Dimensions Table dimensions: 6000 x 2000 mmNumber of T slots: 13T slots dimensions: 22 mm Traverses of axis X axis traverse: 6000 mmY axis traverse: 3800 mmZ axis traverse: 1000 mmVertical capacity (VC): 500 / 1500 mm (direct exit)Distance between columns: 3100 mm Milling head Universal head UM40 (Body B: manual / Body C: 3º auto-indexing) Direct spindleTool clamping system: HydraulicTaper nose: ISO50 (DIN-69871)  /  Pull stud: DIN-69872Speed range: 3000 rpmSpindle power: 30 kW Feedrates Rapid feedrate (X / Y,Z): 7000 / 12000 mm/min Weight and dimensions Maximum weight on table: 15000 kgMachine weight approximate: 50000 KgMachine dimensions approximate: 14740 x 5330 x 5050 mm Accessories Guarding: 2 sliding doors with a new perimetral wire-mesh safety fenceHead changer: automatic with lateral hinge/support in columnChip conveyor: 2 longitudinal palletsElectronic handwheel: New HR-510Coolant: External Internal high pressure through spindle (internal only with direct exit head) Sale conditions Warranty: 6 months mechanical spare partsPrice and sale conditions: On request View all technical features

Condition: good (used), Year of construction: 1989, Universal head (U-25) Coolant system Hydraulic tool clamping X-Axis: 5000mm Y-Axis: 1200mm Z-Axis: 1500mm Table Length: 5000mm Table Width: 1000mm Table load: 7000 Power on spindle:19kW Spindle speeds: 14 - 2500Rpm Spindle Taper: 50ISO/Bt/Mk Feed rate X-Axis:5000mm/min. Feed rate Y-Axis:7000mm/min. Length: 11225mm Width: 4100mm Height: 3200mm Guodpfjwq Rkuox Angjh Weight: 19000kg

Condition: used, Year of construction: 2002, Tiger TFA 5 RT CNC Bed Milling Machine Manufacturer: Tiger S.p.A. (Italy) Model: TFA 5 RT Machine Type: CNC Bed Milling Machine with Rotary Table Year of Manufacture: 2002 Serial Number: 4211 Order No.: 2507 Working Area X-axis travel: 1,500 mm Y-axis travel: 800 mm Z-axis travel: 1,300 mm Rotary Table Guedpfx Ajzqcy Sengsh Table size: 1,020 × 1,200 mm T-slot width: 22 mm (H7 reference slot) Number of T-slots: 7 T-slot spacing: 140 mm Maximum table load: 5,500 kg Feed Rates Working feed: 0–4,000 mm/min Rapid traverse: 12,000 mm/min Axis Drive Torque X-axis: 18–33 Nm Y-axis: 14 Nm Z-axis: 27–33 Nm Spindle Spindle taper: ISO 50 Tool clamping force: 15,000 N Spindle motor power: 20 kW Maximum spindle speed: 2,500 rpm Number of speed ranges: 2 Spindle Speed Ranges Constant torque Range I: 10–272 rpm Range II: 10–658 rpm Constant power Range I: 272–518 rpm Range II: 658–2,500 rpm Accuracy Ballscrew precision class: IT5 (ISO 3408/3) Electrical Specifications Supply voltage: 400 V Power supply: 3-phase Frequency: 50 Hz Installed power: 30 kW Maximum installed power (nameplate): 50 kW Rated current: 40 A Maximum current: 80 A Control voltage: 24 V DC Auxiliary voltage: 220 V Electrical protection: IP54 Motor protection: IP54 Pneumatics Air consumption (6 bar): 600 Nl/min General Machine weight: 12,000 kg Documentation reference weight: 12,500 kg

Condition: used, Year of construction: 2007, functionality: fully functional, Travel ranges: X 7,500 mm Y 1,400 mm Z 1,000 mm Control system: Heidenhain iTNC 530 Milling head: Automatically pivoting diagonal milling head with 2.5° x 2.5° indexing Speed 4,000 rpm, tool holder SK50 Platen table 8,000 x 1,500 mm Mounted NC rotary table 1,000 x 1,000 mm Internal coolant supply Tool changer with 40 positions Gjdpfxez R Surs Angouh Chip conveyor in the X-axis direction 3-sided splash guard enclosure

Condition: used, Year of construction: 1988, x-travel 1800 mm y-travel 700 mm z-travel 1200 mm Gedpezf Nuxjfx Angouh ja 2 control Heidenhain 155 table: 700-2000 mm documentation ja dismantled ja weight of the machine ca. 12,5 t

Condition: like new (used), Year of construction: 2010, Retrofitted: 2026 Numerical control: HEIDENHAIN TNC-i530 Technical features Dimensions Table dimensions: 8500 x 2500 mmNumber of T slots: 17T slots dimensions: 22 mm Traverses of axis X axis traverse: 8000 mmY axis traverse: 3800 mmZ axis traverse: 1500 mmVertical capacity (VC): 168 / 1668 mmDistance between columns: 3100 mm Milling head Auto-indexing differential head (UAD - 0,02º)Tool clamping system: HydraulicTaper nose: ISO50 (DIN69871) / Pull stud: DIN69872Speed range: 6000 rpmSpindle power: 30 kW Feedrates Rapid feedrate (X / Y,Z): 7200 / 12000 mm/min Weight and dimensions Maximum weight on table: 35000 kgMachine weight approximate: 79000 KgMachine dimensions approximate: 22700 x 7660 x 6800 mm Accessories Guarding: 2 sliding doors with a new perimetral wire-mesh fenceAutomatic tool changer: ATC-60Chip conveyor: 2longitudinal hinge typeElectronic handwheel: New HR-510Coolant: External internal high pressure through spindle Sale conditions Warranty: 6 months mechanical spare partsPrice and sale conditions: On request View all technical features Gsdpfx Asz Alwqsngjuh

Year of construction: 1985, condition: ready for operation (used), Travel X/Y/Z: 1300mm/900mm/1000mm, table dimensions X/Y: 2000mm/750mm, max. table load: 5000kg, rapid traverse: 6m/min. Machine dimensions X/Y/Z: approx. 3650mm/2700mm/2700mm, weight: approx. 9000kg, control: Heidenhain TNC 150. Documentation available. An on-site inspection is possible. Godpfx Anow Duuqsgouh

Condition: excellent (used), functionality: fully functional, feed length X-axis: 700 mm, feed length Y-axis: 550 mm, feed length Z-axis: 550 mm, travel distance X-axis: 700 mm, travel distance Y-axis: 550 mm, travel distance Z-axis: 550 mm, HERMLE UWF 1001 CNC milling machine With CNC control, HEIDENHAIN / Type: TNC 155 Machine probe / coolant system Enclosure / cabin / control cabinet: 1260 x 500 x 1700 mm Gsdpfx Asz Dum Usngouh Travel ranges 700 x 550 x 550 mm / Clamping area, table surface: 1000 x 490 mm

Condition: excellent (used), Year of construction: 2012, XYZ SMX 4000 ProtoTRAK CNC Bed Milling Machine ProtoTRAK SMX Control Year of Manufacture 2012 Spindle: 7.5Hp – Programmable 70 – 5000rpm ISO40 Quill Dia 105mm Table: 1474 x 355mm Max load 850kgs Travel: X – 1,060mm Y – 596mm Z – 520mm Dims without travels: W - 2370mm D – 2485mm Guedpfsyzf Naex Angeh H – 2660mm Weight - 3100Kgs For Sale with Jet Machinery Ltd Jet Machinery Stock No: #79167 Machine Serial Number: 10836 Cost: £22,500.00 + VAT Whilst every effort has been made to ensure that the above information is accurate it is not guaranteed. We advise prospective purchasers to check any vital details. Health and Safety At Work Act 1974: It is not reasonably practical for ourselves as suppliers to ensure that for your application the goods comply with requirements of the Act with respect to guarding etc. Prospective purchasers should ensure that a guarding specialist inspect the goods prior to use.

Condition: excellent (used), Year of construction: 1984, functionality: fully functional, travel distance X-axis: 760 mm, travel distance Y-axis: 370 mm, travel distance Z-axis: 335 mm, rapid traverse X-axis: 5 m/min, rapid traverse Y-axis: 5 m/min, table width: 420 mm, table length: 1,200 mm, spindle mount: MK 4, total height: 2,310 mm, total width: 1,900 mm, total length: 2,650 mm, type of input current: three-phase, rotational speed (max.): 4,000 rpm, rotational speed (min.): 40 rpm, workpiece weight (max.): 405 kg, quill travel distance: 150 mm, power: 6 kW (8.16 HP), Equipment: rotational speed infinitely variable, Type control: Heidenhein 150 Gjdpfxounhy Sj Angeuh System resolution: 0,001 mm Documentation for machine

Condition: used, Year of construction: 1999, x-travel 4000 mm y-travel 1000 mm z-travel 1500 mm Control Heidenhain 355 weight max. 10 t ja more pictures available Guodpfxexzuz No Angjh

Condition: ready for operation (used), Year of construction: 2000, operating hours: 22,000 h, functionality: fully functional, machine/vehicle number: 28217, travel distance X-axis: 2,700 mm, travel distance Y-axis: 1,200 mm, travel distance Z-axis: 1,500 mm, spindle speed (max.): 6,000 rpm, overall weight: 18,500 kg, The combination of the Zayer 20 KF 3000 machine, the Heidenhain TNC 426 control system, and a swivel universal head (Huron type) transforms this milling machine into a versatile and powerful production hub. The swivel head completely eliminates the biggest drawback of large machines – the need to constantly reposition and re-clamp heavy workpieces for machining at different angles. Here’s how precisely this head works with the Heidenhain system and what possibilities it offers. Kinematics and capabilities of the swivel head. The head in ZAYER machines consists of two inclined dividing planes that rotate relative to each other. This design allows for: Transition from vertical to horizontal: In a few moments, you can change the machine from a vertical machining center to a horizontal milling machine. This makes it possible, for example, to simultaneously machine the top of a workpiece and, a moment later, mill its sides. Milling at any angle: The head allows you to position the spindle in space at unusual angles, which is crucial for machining inclined surfaces, chamfering large plates, or creating converging pockets. Enormous rigidity: Although the head is movable, its design locks with tremendous force (mechanically or hydraulically). The machine does not lose any of its ability to perform heavy rough machining (so-called “hogging” with a large chip). Cycle 19 and PLANE in Heidenhain TNC 426 – The magic of software. The biggest challenge with a swivel head is the mathematics – when you tilt the tool, the zero points in the X, Y, and Z axes change. Heidenhain TNC 426 solves this automatically using dedicated geometric functions: Cycle 19 (Machining Plane): You inform the control system of the angle at which you have physically rotated the head. The computer immediately recalculates the entire coordinate system. The tool moves in the axis at an angle, and you program as if you were working on a flat surface. Coordinate transformation: You don't have to manually calculate the tool offset after rotating the head. The controller knows the exact dimensions of the machine's kinematics and automatically corrects the position of the X, Y, and Z axes. Angular drilling: After calling Cycle 19, the standard drilling cycle (e.g., deep drilling) automatically performs the feed movement in the inclined axis – the operator writes the program in the Z axis, and the machine physically moves with a combination of the X, Y, and Z axes. Production benefits in the workshop. Machining 5 sides of a workpiece from a single setup: You place a 5-ton steel block on the table. You clamp it once. By rotating the head, you machine the top and all four sides without moving the workpiece with a crane. This guarantees perfect maintenance of geometric tolerances (perpendicularity and parallelism of the surfaces). Time savings and safety: Repositioning a large workpiece on the table often takes hours and carries the risk of accidents or damage to the table. With this head, you only reposition the tool – manually using dividing plates or in an automatic version from the program. Gsdpfszrd Tvox Angsuh

Condition: used, Year of construction: 2017, controller manufacturer: Heidenhain, controller model: TNC 640, _____ Description: Year of manuf. : 2017 Control : Heidenhain TNC 640 Speed : 5000 rpm Movement X/Y/Z : 4500/1800/1300 mm In General: Year of manufacture:2017 Control system:Heidenhain TNC 640 Travel range X/Y/Z:4,500/1,800/1,300 mm Spindle speed:5,000 rpm Tool holder:SK 50 Milling head (spindle): Gsdpfxey Eu Tve Angeuh Technology:Diagonal head with gear spindle Index:0.001° Speed:5,000 rpm Tool holder:SK 50 Max. power:43 kW Max. torque:1,045 Nm Coolant supply:Coolant + blast air Working table: Clamping surface:6,000 x 1,100 mm T-slots:6 x 22H12, spacing 140 mm Tool magazin: Technology:Chain magazine Number of stations:40 Tool changer:Double gripper (horizontal/vertical) Max. tool diameter:125 (250) mm Max. tool length:400 mm Equipment: Position measurement systems:Direct scales Chip removal:Chip conveyor Coolant supply:Internal coolant system with filter, 20 bar Workpiece measurement:Funk M&H probe Set-up operation:HR 510 electronic handwheel Software option:Adaptive Control

Condition: used, Year of construction: 1996, total height: 3,200 mm, total width: 3,200 mm, total length: 8,000 mm, Empty weight: 26.000 kg Price: On request Bed Milling machine Bed Miller Model: CNC Manufacturer: Anayak Type: FBZ-HV-4000 CNC: Heidenhain Year: 1996 Bed-dimensions: 4500x800mm X-travel: 4000mm Y-travel: 935mm Z-travel: 1000mm Rotatable Fräsekopf Spindle-speed: 3000rpm Spindle-take: ISO 50 Incl. peripherals and documents Dismantled for transport Video available! Machine-dimensions: 8000x3200x3000mm Machine-weight: 26000kg - Year: 1996 - Documentation available: Yes - CE marking present: Yes - Serial number: 11676-FBZ - Drive system: CNC - Control system brand: Heidenhain - Number of axes [pcs]: 3 - X-axis travel [mm]: 4000 - Y-axis travel [mm]: 935 - Z-axis travel [mm]: 1000 - Table length [mm]: 4500 - Table width [mm]: 800 - Tool holder: ISO50 - Max. spindle speed [rpm]: 3000 Guedpjz R N Ddofx Angeh - Transport dimensions: 8000mm x 3200mm x 3200mm (l x w x h) - Transport weight [kg]: 26000kg - Transport packages [pcs.]: 1 Financial information VAT: The price shown is exclusive of VAT VAT/margin: VAT deductible for entrepreneurs Delivery and trade-in always possible for everything in the industrial sectors Lukas van Rossum

Condition: ready for operation (used), Year of construction: 2003, CNC Milling Machine OPS Type OPS HSC 600 Year of manufacture 2003 CNC control system Andronic 3D path control with Ethernet interface Travel distances X/Y/Z 625/375/350 mm Tool changer based on Erowa system, 40 positions Spindle speeds 5000 – 40,000 rpm Fixed table, load capacity up to 600 kg Travel speed up to 20 m/min Gsdpfjz Ixkfox Angjuh Repeatability 0.002 mm Tool changer, 32 positions Spindle HSK 32 E Drive power 9 kW Weight 3500 kg Price: Euro 3,750.00 (plus VAT), ex works

Condition: used, Year of construction: 2004, x-travel 4000 mm y-travel 1200 mm z-travel 1500 mm table-size 4200 x 1100 mm tool adaptor SK 50 | turning speed range 5000 U/min power requirement 37 kW control Heidenhain iTNC 530 table load 6,0 t milling head -swivable A= 1,0°/ B= 1,0° Grad tool change unit 60 SK 50 range L-W-H 11,0 x 5,0 x 4,0 m Universale CNC- bed milling machine with extra round table H/V - internal coolant - filter system - oil cooler - external handwheel - chipconveyor Gusdpfxjz It Dto Angeh

Condition: ready for operation (used), Travel X/Y/Z: 1400mm/1000mm/1000mm, table dimensions X/Y: 1600mm/850mm, max. table load: 2500kg, speed: 4000rpm, spindle power: 22kW, feed: 20m/min, spindle taper: ISO50. Machine dimensions X/Y/Z: approx. 4300mm/2500mm/2600mm, weight: approx. 10000kg. An on-site inspection is possible. Guedoy Hk Ulspfx Angoh

Condition: excellent (used), Huron SXB 523 CNC Bed Milling Machine Heidenhain CNC control Year 1991 Table 110" / 2794mm x 24" / 609 7,716lbs / 3499kgs max table load 78.7" / 1998mm X travel 59" / 1498mm Y travel 33.5" / 850mm Z travel 30-3000RPM spindle Gsdpsz Hdvkefx Angouh 30 ATC 3 Axis