Vodoravno nakup rabljenega (235)

Stanje: zelo dobro (rabljeno), MTF horizontal angled conveyor, 3,100 x 400 mm wide, low profile on rollers, year of manufacture: 2015, price: €1,750, contact person: Mr. Rainer Eckerle. Prodpfxsffwg As Agpod

Stanje: rabljeno, Leto izdelave: 1980, številka stroja/vozila: 19780, Grinding length: 600 mm Psdecxxrzopfx Agpjrd Grinding width: 300 mm Workpiece height: 375 mm Spindle speed range: 1,000 – 3,000 rpm Grinding wheel dimensions: 300 x 50 x 76.2 mm Grinding spindle drive: 2.8 – 8.4 kW Machine weight approx.: 3.5 t CNC-controlled surface grinding machine with 3D-controlled profile dresser, ELB CNC control unit Unicon with integrated electronic handwheel, monitor, analogue spindle load indicator, infinitely variable cross feed, coolant system with magnetic roller separator, full enclosure, separate control cabinet, additional grinding wheel with flange.

Stanje: rabljeno, Horizontal Nienkemper BS0 Band Resaw Predpfxoci Df Ao Agped Wheel diameter: 1100 mm with mechanical hand clamping carriage

Stanje: rabljeno, Pressing force 32 t Stroke 250 mm Table size 500 x 760 mm Working height 925 mm Bending speed max. 25 mm/sec Prsdpegvkigsfx Agpod Tank capacity 80 l Pressure capacity 320 bar Total connected load 5.5 kW Machine weight approx. 0.8 t Space requirement approx. 1.3 x 0.5 x 1.3 m Max. bending height: 200 mm Max. cutting capacity (steel): 150 x 14 Max. punching capacity (steel) Ø 35 Straightening height: 200 mm

Stanje: novo, Cutting capacity at 90 degrees (round): 240 mm Cutting capacity at 90 degrees (square): 240 mm Cutting capacity at 90 degrees (rectangular): 165 x 310 mm Saw blade length: 2,725 x 27 x 0.9 mm Table height: 940 mm Band speed: 35 / 70 m/min Total power requirement: 1.1 kW Machine weight: approx. 0.4 t The Z252/DGH is equipped with: - Hydraulic semi-automatic operation - Double mitre, 60° left / 45° right - Emulsion pump - Machine base - Saw blade Prsdpfx Agsfgyh Hjpod - 400V, 16A plug The machine is delivered fully assembled and ready for immediate operation.

Stanje: rabljeno, Horizontal conveyor belt, 13,500 x 800 mm wide, 13.5 m long, price: €4,900, contact person: Mr. Rainer Eckerle. Pedj R U U Aepfx Agpjrd

Stanje: rabljeno, Leto izdelave: 1982, Grinding length: 500 mm Grinding width: 225 mm Workpiece height: 400 mm Total power requirement: 5.5 kW Machine weight approx.: 3.4 t Prsdpfx Agscxxtmjpsd with NC control NC81, table toothed belt drive 100-25000 mm/min, automatic infeed, electronic straight dressing with speed compensation, coolant pump, emergency stop safety device

Stanje: novo, Cutting capacity at 90°: round 680 mm Cutting capacity at 90°: square 640 mm Cutting capacity at 90°: rectangular 1250 x 600 mm Cutting capacity at 45°: round 680 mm Cutting capacity at 45°: square 600 mm Cutting capacity at 45°: flat 870 x 600 mm Cutting capacity at 60°: round 580/550 mm Cutting capacity at 60°: square 530/450 mm Cutting capacity at 60°: flat 550 x 450 mm Saw blade length 8140 x 54 x 1.6 mm Blade speed 15 - 90 m/min Table height 855 mm Total power requirement 7.5 kW Machine weight approx. 5.3 t Space requirements approx. 5.75 x 4.2 x 2.75 m 2-column double mitre band saw designed for high-speed cutting with pusher system P15. Optionally with P30 Hydraulic lowering of the saw frame • NC controlled • Automatic angle positioning from +60° to -60° High-quality automatic mitre adjustment Specially developed for cutting profiles and beams. Maximum positioning accuracy is achieved using the new "B&S positioning system". An intelligent NC control system ensures smooth interaction between the linear encoder and the self-braking positioning motor in combination with a reliable hydraulic brake by means of large-radial center positioning. The work table is supported by high-quality preloaded bearings, which ensure very smooth rotation. CNC control CNC control allows the programming of up to 90 cutting programs Prjdpfx Agsfg E Hnopjd with different cut lengths, quantities and mitre angles. Dual-side clamping positioning system The B&S pusher system – feed and positioning system – is equipped with "double-sided opening grippers" which are hydraulically operated. This guarantees safe gripping and transport of materials and bundles that deviate slightly from their ideal shape. The pusher system is independently mounted and guided via ball-bearing linear guides, precision ground rack, and a frequency-driven, robust gear motor.

Stanje: novo, Cutting range at 90 degrees: round 310 mm Cutting range at 90 degrees: square 280 mm Cutting range at 90 degrees: rectangle 400x250 mm Saw blade length 4020x34x1.1 mm Blade speed 18 - 100 m/min Table height 890 mm Total power requirement 2.2 kW Machine weight approx. 0.99 t Space required approx. 1.85 x 2.2 x 2.0 m Mitre Band Saw, Fully Automatic, GBS 310/400 VA-I CNC - Mitre left 45° automatic operation - Mitre left 60° semi-automatic operation (cuts without programming) - Material height sensor (automatic cut start detection) - Frame and gearbox cast in one piece, ensuring very quiet and low-vibration operation - Removable chip tray (for cleaning/disinfection) - Impact-resistant and ergonomic control panel with oil-resistant EPDM cover - Excellent access to saw, material, and feed unit - Folding safety cover - Fine adjustment for feed - Semi-automatic cutting - Optimize workflows with CNC control: possibility to input various parameters such as quantities and material lengths, automatic calculation of the cutting channel - CNC control for 10 different sawing programs, each with up to 99 subprograms for different lengths and quantities, e.g. one cutting program with various section lengths - Automatic feed unit (CNC) via ball screw with incremental feed and automatic length compensation. Adjustable for section lengths from 2 mm up to 9,999 mm, remnant length 170 mm. Prjdpfxsd Iipre Agpod

Stanje: novo, Cutting diameter round: 300 mm Cutting diameter square: 300 mm Cutting diameter flat: 300 x 260 mm Saw band length: 3920 x 34 x 1.1 mm Table height: 780 mm Band speed: 20 - 100 m/min Total power requirement: 3.7 kW Machine weight: approx. 1.65 t Dimensions (L x W x H): 2.0 x 2.05 x 1.7 m SPECIAL OFFER PRICE!!!! 2-Column Heavy-Duty Bandsaw Machines of the SBS Series The SBS series impresses with advanced technology, high quality, durability, and an unrivalled comprehensive standard configuration. • Modern SNC 20 controller for CNC models • Frequency-controlled saw drive • Control buttons featuring pictograms • Work light • Powered chip brush • Hydraulic blade tensioning • Clamping pressure adjustment Prjdpfx Ajfb Nbfjgpod • Double vice (in front of and behind the band) • Creep speed for positioning • Bundle clamping prepared for electric and hydraulic operation • Chip conveyor The SNC 20 controller allows convenient and straightforward input of up to 20 different cutting programs (length and quantity). When the target dimension is entered, the control system automatically calculates the trim loss and the number of feed strokes. Furthermore, the error code display system provides rapid diagnosis for troubleshooting.

Stanje: novo, Cutting diameter: 255 mm Saw band length: 2765 x 0.9 x 27 mm Cut width: 300 x 180 mm Speeds: 35 + 70 rpm Total power requirement: 1.8 kW Machine weight: approx. 450 kg Space requirement: approx. 1.7 x 1.23 x 1.75 m SPECIAL OFFER!!! Double-mitre metal band saw, frequency inverter, hydraulic semi-automatic GBS 250 Super HA-I Easy • Mitre cuts: left 60° + right 45° • Material height sensor (automatic cut start detection) • Frame and gearbox made from a single casting: extremely quiet and low-vibration operation Prjdpfx Aofn Andogpjd • Hydraulically operated vice, laterally adjustable • Guided, high-quality industrial bearings • Heavy-duty vice and machine cast frame • Large machine bed • Machine base with tool compartment and chip drawer • Cut monitoring via ammeter • Adjustable cutting pressure feed regulator • Support roller on infeed side • Ball-bearing rotary table Semi-automatic operation: 1. Clamp material 2. Start saw 3. Rapid descent to material start or, for serial cutting, start cutting immediately 4. Stop saw band 5. Raise frame slightly above the material 6. Open vice

Stanje: novo, Cutting diameter: 227 mm Pedpfx Asfgyh Eegpsrd Saw band length: 2455 mm Table height: 840 mm Cutting width: 260 mm Speed range: 36 / 72 m/min Saw blade dimensions: 2455 x 27 x 0.9 mm Cutting area at 90 degrees (round): 227 mm Cutting area at 90 degrees (square): 220 mm Cutting area at 90 degrees (flat): 260 x 220 mm Cutting area at 45 degrees (round): 150 mm Cutting area at 45 degrees (square): 145 mm Cutting area at 45 degrees (flat): 200 x 220 mm Total power requirement: 1.5 kW Machine weight approx. 0.25 t Space requirement approx. 0.8 x 1.4 x 1.5 m Mitre band saw - automatic cutting - base frame - coolant pump - chip brush for saw blade cleaning - quick-adjust vice

Stanje: novo, Cutting capacity at 90°: round 255 mm Cutting capacity at 90°: square 240 mm Cutting capacity at 90°: rectangular 300 x 180 mm Saw blade length: 2,765 x 27 x 0.9 mm Table height: 950 mm Band speed: 18 - 110 m/min Total power requirement: 1.5 kW Machine weight approx. 0.42 t Space requirement approx. 1.23 x 1.7 x 1.75 m SPECIAL PRICE!!! Double mitre metal band saw, frequency inverter, hydraulic semi-automatic GBS 250 Super HA-I Easy • Mitre cuts left 60° / right 45° • Material height sensor (automatic cut start detection) • One-piece cast frame and gearbox, extremely quiet and low-vibration operation • Hydraulically movable vice • Guided, high-quality industrial bearings • Heavy-duty vice & machine casting • Large machine bed • Machine base with tool compartment and chip drawer • Cut monitoring via ammeter • Adjustable feed pressure regulator • Infeed support roller • Ball-bearing turntable Semi-automatic operation: 1. Clamp material Predpfx Agofgyh Uepod 2. Saw starts 3. Rapid downfeed to material or, for series cutting, direct cutting 4. Saw blade stops 5. Raise frame just above the material 6. Open vice

Stanje: novo, Cutting capacity at 90°: round 305 mm Cutting capacity at 90°: square 260 mm Cutting capacity at 90°: rectangle 350 x 200 mm Pedpfx Ajfgyiasgperd Saw band length 3375 x 27 x 0.9 mm Band speed 18 – 100 m/min Table height 940 mm Total connected load 1.5 kW Machine weight approx. 0.65 t Space requirement approx. 1.5 x 1.75 x 1.9 m SPECIAL OFFER PRICE!!! Double miter metal band saw, hydraulic semi-automatic GBS 305 HA-I Easy - Miter cuts up to 60° left and 45° right - Material height sensor - Ball-bearing turntable - Hydraulic vice, laterally adjustable - Heavy-duty, large material support - Automatic coolant system

Stanje: novo, Cutting capacity at 90° (round): 350 mm Cutting capacity at 90° (square): 330 mm Cutting capacity at 90° (rectangle): 450 x 320 mm Saw band length: 4250 x 34 x 1.1 mm Band speed: 40 + 80 m/min Table height: 845 mm Saw blade width: 34 mm Total power requirement: 2.2 kW Machine weight: approx. 0.985 t Space requirements: approx. 1.4 x 2.0 x 2.2 m Double mitre band saw, hydraulic semi-automatic, DGS 350/450 HA-I • Mitre cuts left & right up to 60° without machine conversion • 34 mm saw blade width • Large, ball-bearing supported, rotary worktable • Saw blade guides adjustable over extra-wide linear rails • Heavy-duty, robust gearbox • Large-area clamping plates • Infeed and outfeed roller • Removable chip tray (for cleaning) • Free-standing, safe, ergonomic control panel • Storage space for blades and consumables • Cutting pressure control and feed rate regulator • Fully hydraulic vice • Quick clamping (front loading) • Material height sensor (automatic cut start detection) Semi-automatic operation: 1. Clamp material 2. Start saw 3. Rapid descent to start of material or direct cutting for series cuts 4. Switch off saw band 5. Raise frame just above the material 6. Open vice Optimal, material-independent cutting results through fine adjustment of the saw frame via: * Pressure control valve (cutting force) Pedefgyicepfx Agpord * Feed rate control valve (cutting speed) * Clearly arranged selector switch with pictograms for intuitive operation

Stanje: novo, Cutting range at 90°: round 680 mm Psdofgyigepfx Agpsrd Cutting range at 90°: square 640 mm Cutting range at 90°: rectangle 1250x600 mm Saw band length: 8140x54x1.6 mm Band speed: 15 - 90 m/min Table height: 855 mm Total power requirement: 7.5 kW Machine weight approx. 4.96 t Space requirement approx. 5.7 x 4.0 x 2.75 m 2-column bandsaw for fast cutting, K-tech 1200H with pusher system P 30. P 60 (optional). Fast, smooth, and ergonomic cutting Specially designed for cutting profiles and beams as well as solid material. The material is clamped vertically on both the infeed and outfeed sides. Starting from model K-tech 800 H, the machine is equipped as standard with an additional horizontal vice. The interplay of hydraulic saw frame descent, material positioning, and the pusher system is CNC-controlled. The machines are equipped as standard with the environmentally friendly "B&S Clean Cut" cutting system with minimum quantity lubrication. This reduces cleaning requirements and conserves resources. CNC control A CNC control system allows programming of up to 90 cutting programs with different cut lengths, quantities, and mitre angles. The B&S pusher system, feeding and positioning unit, is equipped with 'double-sided opening clamping jaws' which are hydraulically operated. This ensures secure gripping and transportation of materials and bundles that may deviate somewhat from the ideal shape. The pusher system is built separately and is guided via ball-bearing linear guides, precision-ground rack, and a frequency-driven, robust geared motor.

Stanje: novo, Cutting capacity at 90°: round 350 mm Cutting capacity at 90°: square 330 mm Cutting capacity at 90°: rectangle 500 x 310 mm Band speed: 15 - 100 m/min Table height: 844 mm Saw blade dimensions: 4250 x 34 x 1.1 mm Total power requirement: 2.2 kW Machine weight approx. 1.2 t Space requirements approx. 1.4 x 2.4 x 1.935 m Prjdpfxofg E Hle Agpsd SPECIAL OFFER PRICE!!! 2-Column Double Mitre Bandsaw K-tech DG 50/33 HA-I • 2-column mitre saw • Robust yet easy to operate • Material height sensor (automatic cut start detection) • Smooth running thanks to angled cut, feed regulator and cutting pressure regulator • Heavy-duty material infeed roller • Removable chip tray (for cleaning) • Energy-efficient and low vibration thanks to angled cut • Ergonomic, safe and free-standing control panel • Frequency-controlled saw drive 15 – 100 m/min • Hydraulic cutting pressure control valve • Hydraulic control of saw frame and vices • LEDs for monitoring all safety functions • Large-dimension drive wheels (520 mm) dia. • Intuitive mitre angle adjustment up to 60° Semi-automatic operation: 1. Clamp material 2. Saw starts 3. Rapid downfeed to start of material or immediate cutting for serial cuts 4. Saw band off 5. Raise frame just above material 6. Open vice

Stanje: novo, Cutting capacity at 90°: round 305 mm Cutting capacity at 90°: square 260 mm Cutting capacity at 90°: rectangle 350 x 200 mm Prodsd Iipxepfx Agpod Saw blade length: 3375 x 27 x 0.9 mm Blade speed: 37 + 74 m/min Table height: 940 mm Total power requirement: 1.5/1.8 kW Machine weight approx. 0.65 t Space requirement approx. 1.5 x 1.75 x 1.9 m SPECIAL PRICE!!! Double miter metal band saw, hydraulic semi-automatic GBS 305 HA-I Easy - Miter cuts up to 60° left and 45° right - Material height sensor - Ball-bearing rotary table - Hydraulically operated, laterally adjustable vice - Heavy-duty, large material support - Automatic coolant system

Stanje: novo, Cutting range at 90 degrees: round 250 mm Cutting range at 90 degrees: square 210 mm Cutting range at 90 degrees: rectangle 290 x 210 mm Saw band length: 2,965 x 27 x 0.9 mm Table height: 940 mm Band speed: 35 + 70 m/min Total power requirement: 1.1 / 1.3 kW Machine weight approx. 0.35 t Space requirement approx. 1.3 x 0.8 x 1.5 m Predpfx Agjd Iip Nopsd SPECIAL PROMOTIONAL PRICE!!! Double mitre metal bandsaw featuring: - Band speed 35 + 70 m/min - Mitre cuts up to 60° left and 45° right - Ball-bearing turntable for rapid mitre adjustment - Movable quick-action vice - Quick-release lever - Automatic coolant system

Stanje: novo, Cutting range at 90°: round 255 mm Cutting range at 90°: square 240 mm Cutting range at 90°: rectangular 300 x 180 mm Saw band length: 2,765 x 27 x 0.9 mm Table height: 870 mm Band speed: 18 – 110 m/min Total power requirement: 1.5/1.8 kW Machine weight approx. 0.63 t Space requirements approx. 1.8 x 1.85 x 1.85 m Mitre Band Saw, Fully Automatic GBS 250 Super VA-I MPS - Mitre left 45° in automatic mode - Mitre left 60° in semi-automatic mode (cuts without programming) - Impact-resistant and ergonomic control panel with oil-resistant EPDM cover - Material height sensor (automatic cutting start detection) - One-piece cast frame and gearbox for extremely quiet and low-vibration operation - Removable chip tray (easy cleaning/disinfection) - Excellent accessibility to saw, material, and feed unit - Hinged safety cover - Fine adjustment for feed rate - Semi-automatic cutting! Automatic sawing with microprocessor control Selectable for 2 programmable levels Semi-automatic operation Fully automatic operation Start cycle after input of desired quantity and material length: material approach, cutting, and piece counting until program fulfillment - MPS control system for input of required number of feed cycles - All essential machine data displayed on the LED display during the cutting process (current draw, cutting time, piece count) - Entered data is retained in RAM memory - The self-diagnostic circuit automatically displays any irregularities as error messages and monitors the entire process - Floating feed unit Pjdpfxsd Iip Ao Agperd - Length adjustment using handwheel and vernier scale with mechanical position display. Adjustable for cut lengths from 2.5 mm to 420 mm or, using the reversing automatic, 1–29 repetitions, remnant length 210 mm

Stanje: novo, Cutting diameter round: 330 mm Cutting diameter square: 330 mm Cutting diameter flat: 400x330 mm Saw band length: 4570 x 34 x 1.1 mm Table height: 800 mm Band speed: 20 - 100 m/min Total power requirement: 3.7 kW Machine weight approx. 2.35 t Dimensions (L x W x H): 2.23 x 2.15 x 1.8 m SPECIAL OFFER PRICE!!!! 2-column high-performance automatic band saws of the SBS series The SBS series impresses with advanced engineering, high quality, durability, and an unrivaled comprehensive standard equipment package. - Modern SNC 20 controller for CNC models Prodpfx Ajfb Nbgogpod - Frequency-controlled saw drive - Control buttons with pictograms - Work light - Powered chip brush - Hydraulic blade tensioning - Clamping pressure regulation - Double vice (in front of and behind the band) - Inch mode for positioning - Bundle clamping, pre-configured electrically and hydraulically - Chip conveyor The SNC 20 controller enables user-friendly and straightforward input of up to 20 different sawing tasks (length and quantity). When entering the desired measurement, the controller automatically calculates the saw cut allowance and the number of feed strokes. Additionally, the error code display system provides rapid fault analysis for troubleshooting.

Stanje: novo, Cutting range at 90°: round 680 mm Cutting range at 90°: square 640 mm Cutting range at 90°: rectangle 820x610 mm Cutting range at 45°: round 550 mm Cutting range at 45°: square 550 mm Cutting range at 45°: flat 550x600 mm Cutting range at 60°: round 370 mm Cutting range at 60°: square 370 mm Cutting range at 60°: flat 370x600/450 mm Saw blade length: 7260 x 41 x 1.3 mm Band speed: 15 – 100 m/min Table height: 800 mm Total power requirement: 5.5 kW Machine weight: approx. 4.8 t Space requirement: approx. 5.85 x 3.7 x 2.7 m 2-column double miter band saw for high-speed cutting with pusher system P15, option P30 Hydraulic saw frame lowering - NC controlled - Automatic angle positioning from +60° to -60° High-quality automatic miter adjustment Specially designed for cutting profiles and beams. The highest positioning accuracy is achieved with the new "B&S positioning system". An intelligent NC control ensures smooth coordination of linear encoder and self-braking positioning motor, in combination with a reliable hydraulic brake via large-radial center positioning. The work table is mounted via high-quality preloaded bearings, ensuring Predpsfg E Hmsfx Agpjd very smooth rotation. CNC control A CNC control allows the programming of up to 90 cutting programs with different section lengths, quantities, and miters. Dual-side gripping positioning system The B&S pusher system, feed and positioning system, is equipped with 'dual-side opening grippers' which are hydraulically actuated. This guarantees secure gripping and conveying of materials and bundles that deviate from ideal form. The pusher system is constructed separately and is guided by ball-bearing linear guides, ground rack, and a frequency-driven, robust gear motor.

Stanje: novo, Cutting diameter round: 460 mm Cutting diameter square: 460 mm Cutting diameter flat: 460 x 460 mm Saw band length: 5450 x 41 x 1.3 mm Table height: 800 mm Band speed: 20 - 100 m/min Total power requirement: 5.5 kW Machine weight: approx. 3.2 t Dimensions L x W x H: 2,675 x 2.15 x 2.05 m SPECIAL PRICE!!!! 2-column high-performance bandsaw machines of the SBS series The SBS series impresses with advanced technology, high quality, durability, and a uniquely comprehensive standard equipment package. • Modern SNC 20 control for CNC versions • Frequency-controlled saw drive • Control buttons with pictograms • Work light • Powered chip brush • Hydraulic band tensioning • Adjustable clamping pressure Predpefg E Hvofx Agpod • Double vice (before and after the band) • Inch mode for positioning • Bundle clamping, prepared for electric and hydraulic operation • Chip conveyor The SNC 20 control allows convenient and simple input of up to 20 different cutting tasks (length and quantity). Upon entering the desired dimensions, the controller automatically calculates the trim cut and the number of feed strokes. In addition, the error code display system enables quick analysis for troubleshooting.

Stanje: novo, Cutting capacity at 90°: round 310 mm Cutting capacity at 90°: square 280 mm Cutting capacity at 90°: rectangle 400 x 250 mm Saw blade length: 4020 x 34 x 1.1 mm Blade speed: 37 + 74 m/min Table height: 940 mm Total power requirement: 1.8/2.2 kW Machine weight: approx. 0.68 t Space requirement: approx. 1.5 x 1.78 x 1.3 m SPECIAL OFFER PRICE!!! Double miter bandsaw, hydraulic semi-automatic, GBS 310/400 HA-I Easy • Miter cut left 60° / right 45° • Heavy-duty industrial hydraulics, 18 bar • Optimal access to the workpiece • Ammeter for monitoring: - Cutting force optimization Psdpfxod Iiptj Agpord - Blade life - Cut accuracy • Hydraulic vice: automatic clamping and release • Swarf removal brush • Material turntable with ball bearings • Quick-release vice, movable • Height sensor for material (automatic cut start detection) Semi-automatic operation: 1. Clamp material 2. Start saw 3. Fast lowering to material, or for serial cuts, start cutting immediately 4. Saw blade stops 5. Raise saw frame slightly above material 6. Release vice

Stanje: novo, Cutting capacity at 90° (round): 250 mm Cutting capacity at 90° (square): 210 mm Cutting capacity at 90° (rectangular): 290 x 210 mm Saw blade length: 2,965 x 27 x 0.9 mm Table height: 940 mm Blade speed: 25 - 90 m/min Total power requirement: 1.1/1.3 kW Machine weight: approx. 0.35 t Space requirement: approx. 1.3 x 0.8 x 1.5 m SPECIAL PRICE!!! Double miter metal band saw Hydraulic semi-automatic with: - Hydraulic vice - Material height sensor - Cut monitoring via ammeter - Cutting pressure and feed rate regulator - Blade speed 25 - 90 m/min Prsdpsfgyh Sefx Agpjd - Miter cuts up to 60° left and 45° right - Patented, ball-bearing rotary table for easy miter adjustment - Movable quick-release vice - Quick-release lever - Automatic cooling system