Used Ostas Plate Roller 4 Rolls for sale (71,785)

Condition: new, Year of construction: 2024, neu 2024 Bjdpfxjwiqpbj Ac Tedg 9722 prompt, Zwischenverkauf v Türkei 17300 € 332.16 € 1 2050 mm 3 mm 130 mm 3,5 m/min 2.2 kW 3200 mm 750 mm 1000 mm 1500 kg 3 rolls asymmetric rolls - prebending 2 rolls driven by brakemotor HARDENED ROLLS manual Back Roll forward tiltable upper roll forward and reverse revs conical bending by tilt of backroll movable control panel users manual in GERMAN OPTIONS (PRICES ON REQUEST): (time of delivery with options approx. 8 weeks) Motorised Back Roll (Power Rear Roll) Digital Read-Out

Condition: new, Year of construction: 2024, neu 2024 9740 prompt, Zwischenverkauf v Bodpowiqnwsfx Ac Tsdg Türkei 6500 € 125.45 € 1 1050 mm 3 mm 90 mm 6 m/min 1.1 kW 1630 mm 700 mm 1200 mm 480 kg 3 rolls asymmetric rolls - prebending 2 rolls driven by brakemotor lateral roll adjustable by handwheel longitudinal grooves in lower and lateral roll tiltable upper roll right / left rotation with double foot switch conical rolling device user manual in GERMAN

Condition: new, neu Bdedpfxewiqnke Ac Tjg ca. 10 Wochen ab Auftrags Türkei 7000 € 135.1 € 1550 mm 2 mm 90 mm 6 m/min 1.5 kW 2130 mm 700 mm 1200 mm 545 kg 3 rolls asymmetric rolls - prebending 2 rolls driven by brakemotor lateral roll adjustable by handwheel longitudinal grooves in lower and lateral roll tiltable upper roll right / left rotation with double foot switch conical rolling device user manual in GERMAN or ENGLISH OPTIONS: powered back roll EUR 1.000,- digital readout EUR 1.100,-

Condition: used, functionality: fully functional, machine/vehicle number: 2550X10.14MM, control type: manual, degree of automation: manual, actuation type: mechanical, number of rollers: 3, roller (top) diameter: 300 mm, side roll diameter: 280 mm, roller diameter: 400 mm, roller length: 2,550 mm, working width: 2,500 mm, working height: 800 mm, sheet thickness (max.): 14 mm, sheet thickness stainless steel (max.): 10 mm, input voltage: 380 V, input frequency: 50 Hz, Equipment: centralized greasing system, cone bending device, emergency stop, swiveling upper roller, 3 roll 2500x14 mm Plate bending machine Model OMCCA ITALY CAPACITY plate width 2500 mm plate thickness 14 mm pre-bending 10 mm Bedpfxey Aubuj Ac Todg --- Useful rollers width 2550 mm Top roll d 300 mm Side rollers D 280 mm hard surface of the 3 rolls centralized gear unit side rolls driven Opening front hydraulic drop-end to unload the closed shell. Extended shafts to take installation of add-on molds for section bending Variable speed rolling up to 5 mtr/min power electric motor 20Hp on hydraulic unit console with electric push buttons commands. Dial gauge position rollers readout safety installations with emergency stop

Condition: like new (used), functionality: fully functional, Year of construction: 2024, control type: CNC control, degree of automation: automatic, actuation type: hydraulic, controller manufacturer: EVO, controller model: EVO 4 AXIS 15", number of rollers: 4, roller (top) diameter: 300 mm, roller diameter: 300 mm, roller length: 3,100 mm, working width: 3,000 mm, working height: 1,250 mm, sheet thickness (max.): 30 mm, sheet thickness steel (max.): 30 mm, sheet thickness stainless steel (max.): 25 mm, overall weight: 17,000 kg, total length: 5,500 mm, total width: 2,000 mm, total height: 2,100 mm, power: 18.5 kW (25.15 HP), input voltage: 400 V, number of digital displays: 4, warranty duration: 12 months, Equipment: cone bending device, documentation/manual, emergency stop, hardened rollers, swiveling upper roller, 4roll hydraulic plate bending machine rated capacity 3000x35 mm MODEL MG M3035 , used year 2024 machine as new with warranty included Bedpjy Tbf Iofx Ac Tjdg Planetary dual pre-pinch Performance Capacity: Plate width 3000 mm plate thickness rolling 30 mm pre-bend 25 mm minimum rolling diameter ID 350 mm max open width plate feed 3100 mm special top roll reduced size 300 mm to achieve rolling ID 350 mm Power electric motor 18.5kw on hydraulic unit Vac 400/50 -480/60 Installed configuration Hardened rolls high surface strength Conical plate rolling, cone bending Electric console remoted on wheels with joysticks and readout CNC programmable 4 axis controller touch screen 15” Setup virtual infinite rolling programs with teach-in mode and cad/cam operator interface --- Hydraulic motorized driven the central rolls Pre-pinch load adjustable for pre-bend Drop-end top roll front open unloading closed shells Re-rolling system for welded shells calibration. Safety and emergency stop Manuals and schematics machine dimension 5500x2000x2100 mm -weight 17ton --- Additional accessories available with the machine See layout drawing in enclosed nr.1 central support hydraulic 2.2 ton capacity to support large shell dia up to 4,5 meters id nr.1 side support hydraulic left side 2.2 ton double arm nr. 1 side support hydraulic right side 2.2ton double arm

Condition: good (used), functionality: fully functional, Year of construction: 1998, control type: NC control, degree of automation: semi-automatic, actuation type: hydraulic, controller manufacturer: Siemens, controller model: Simatic OP7, number of rollers: 4, roller (bottom) diameter: 470 mm, roller (top) diameter: 530 mm, side roll diameter: 400 mm, roller diameter: 530 mm, roller length: 3,100 mm, working width: 3,000 mm, working height: 2,000 mm, sheet thickness (max.): 50 mm, sheet thickness steel (max.): 65 mm, sheet thickness stainless steel (max.): 50 mm, overall weight: 40,000 kg, total length: 6,000 mm, total width: 2,900 mm, total height: 2,900 mm, power: 55 kW (74.78 HP), input voltage: 380 V, input frequency: 50 Hz, number of digital displays: 4, Equipment: cone bending device, documentation/manual, emergency stop, hardened rollers, swiveling upper roller, plate bending roll capacity 3000x50 mm Davi modelMCB3053 Hydraulic 4 roll plate bending machine, year 1998 plate width 3000 mm thickness rolling 50 mm pre-bending 40 mm width on the rolls 3100 mm upper roll size 530 mm lower roll 470 mm side rolls 400 mm Power electric 70Hp on hydraulic unit voltage 380/50 - Installed configuration Hardened surface of the 4 rolls conical bending attachment – hardened cone bending Console electric with digital position readout of the rolls Controller Siemens Simatic OP7 NC programmer for automatic rolling Hydraulic power driven the central rolls with axial gearbox Pre-pinch pressure adjustable plate edge pre-bend. Bdjdpfx Aey D Ngzjc Teg Drop-end open front for unloading closed shells Rerolling system for calibration roundness of welded shells. Safety and emergency system installed. Manuals original for operation and maintenance Dimension 6000x2900 x h 2900 mm weight 40000 kg

Condition: excellent (used), functionality: fully functional, Year of construction: 2000, machine/vehicle number: 3roll 3500x140 mm prepinch, control type: manual, degree of automation: manual, actuation type: hydraulic, controller manufacturer: MG, controller model: MG, number of rollers: 3, roller (bottom) diameter: 880 mm, roller (top) diameter: 950 mm, side roll diameter: 880 mm, roller length: 3,550 mm, working width: 3,500 mm, working height: 3,950 mm, sheet thickness (max.): 140 mm, sheet thickness steel (max.): 175 mm, overall weight: 200,000 kg, total length: 8,800 mm, total width: 5,100 mm, total height: 5,775 mm, power: 200 kW (271.92 HP), input voltage: 380 V, input frequency: 50 Hz, number of digital displays: 2, Equipment: cone bending device, documentation/manual, emergency stop, hardened rollers, Hydraulic Plate Bending machine planetary pinch pyramid with prebend. model MG35140V 3 roll capacity 3500x140 mm The machine was overhauled in 2024, Capacity : Plate width mm. 3500 Plate thickness mm. 140 Capacity chart in enclosed Tech data: -3 rolls driven hydraulic motorized with axial gear unit on each roll independent -Synchronized hydraulic rotation of the 3 rolls with variable speed. -Planetary design with pre-pinch fully hydraulic -Conical plate bending with hardened contrast pad -Digital position readouts of the bending rolls -Rolls installed on bearings double crown heavy duty -Overload safety hydraulic operation protection of the 3 rolls -High pressure hydraulic power pack with multi-pumps oil feed -Centralized control panel electric on wheels with joysticks and digital readouts -Emergency stop with safety system around the machine working area Rolls surface length mm. 3550 Top roll mm. 950 Side rolls mm. 880 Bdodpfeyzim Ajx Ac Tjg Electric power on hydraulic unit Hp 100 + Hp 100 Voltage 380 Vac / 50 Hz Configuration & accessories installed with the machine -Hardened surface of the 3 rolls -Conical plate bending attachment , rolls tilt with contrast roller type. -Centralized operator panel with directional joysticks electric. -Digital position readout of the bending rolls. -Emergency and safety installations, certified CE -User manuals and instruction books in English -Dimension see layout drw in enclosed

Condition: excellent (used), functionality: fully functional, Year of construction: 2001, control type: manual, degree of automation: manual, actuation type: electric, number of rollers: 3, roller (bottom) diameter: 150 mm, roller (top) diameter: 170 mm, side roll diameter: 150 mm, roller length: 2,050 mm, working width: 2,000 mm, working height: 700 mm, sheet thickness (max.): 6 mm, sheet thickness steel (max.): 6 mm, sheet thickness stainless steel (max.): 6 mm, sheet thickness aluminum (max.): 6 mm, sheet thickness brass (max.): 6 mm, sheet thickness copper (max.): 6 mm, overall weight: 1,500 kg, total length: 2,500 mm, total width: 800 mm, total height: 1,100 mm, power: 5 kW (6.80 HP), input voltage: 380 V, input frequency: 50 Hz, Equipment: centralized greasing system, cone bending device, documentation/manual, emergency stop, foot remote control, hardened rollers, PLATE ROLL 2000x6 mm SERGI 3ROLL INITIAL PINCH ASYMMETRIC 2050 X6 MM Rolls length 2050 mm -Top roll 170 mm -lower/Side rolls 150 mm -Power electric 5,5 Hp Capacity -plate width 2000 mm -plate thickness 6 mm with prepinch Configuration on the machine -Rollers surface hardened high strength -Central rolls driven electric rotation on gearunit -side roll electric run with prepinch Pinch roll position with handwheel Bsdpsx Ewa Esfx Ac Tedg Front open manual drop-end -Readout gauge of side bending roll -Foot-pedal electric rollers rotation back/forth -Joystick electric control of side roll -Safety installations with emergency stop.

Condition: used, 4 clamping elements, down-hold clamps, heavy-duty clamping jaws, clamping plate LENZKES type 170796 Plate clamps, flat clamps, deep-jaw clamps, deep clamping jaws, low-profile clamps, clamping jaws Length: 280 mm Width: 200 mm Height: 113 mm Clamping plate width: 89 mm Mounting slot distance: 62.5 / 125 mm Mounting slot width: 27 mm Mounting slot length: 145 / 185 mm Construction height of mounting slot clamping surface: 58.5 mm - Down-hold action via hex socket screw SW17 - Clamping movement via trapezoidal thread spindle Bdjdpfxexy Stgo Ac Tog - Reversible jaws for use on either side along the trapezoidal spindle - Reversible clamping jaws with dovetail guide for changing sides - 3 elongated mounting holes for fastening to the machine table Weight per clamp: 15.5 kg Total weight: 62 kg Very robust design Very good condition

Condition: excellent (used), functionality: fully functional, Year of construction: 1993, control type: manual, degree of automation: manual, actuation type: hydraulic, number of rollers: 3, roller (bottom) diameter: 280 mm, roller (top) diameter: 300 mm, side roll diameter: 280 mm, roller diameter: 400 mm, roller length: 4,050 mm, working width: 4,000 mm, working height: 1,100 mm, sheet thickness (max.): 8 mm, sheet thickness steel (max.): 8 mm, sheet thickness stainless steel (max.): 6 mm, overall weight: 11,000 kg, total length: 6,000 mm, total width: 1,450 mm, total height: 1,510 mm, power: 11.03 kW (15.00 HP), input voltage: 380 V, input frequency: 50 Hz, Equipment: documentation/manual, emergency stop, hardened rollers, 3 roll 4000x8 mm Plate bending machine with pre-pinch Model Famar CPI4/6 CAPACITY plate width 4000 mm plate thickness 8 mm pre-bending 6 mm --- Useful rollers width 4050 mm Top roll d 300 mm Bdedpfx Aexnmb Isc Tjg Side rollers D 280 mm hardened surface of the 3 rolls position readout of the bending rollers Opening front hydraulic drop-end to unload the closed shell. Extended shafts to take installation of add-on rollers for profile bending Variable speed rolling up to 5 mtr/min power electric motor 15Hp on hydraulic unit 15Hp-Voltage 380/50 safety installations with emergency stop dimension 6000x1450 x H 1510 weight 11 Ton

Condition: new, Isitan Hydraulic 4-Roll Round Bending Machine 4R HMS 2050x200 2 Speeds Top and bottom rolls driven Hydraulic side roll adjustment 3 Digital displays Hydraulic folding bearing Hardened rolls Tapered bending device Separate control panel Useful length: 2050 mm Top roll diameter: 200 mm Side roll diameter: 180 mm Total motor power: 5.5 KW Working speed: 3 m/min. – 6 m/min. Weight: 3750 kg Dimensions (mm): 3850 x 1350 x 1290 (L x W x H) Bending performance data 10 mm at the smallest inner diameter of 1000 mm (5 x top roll) Bdsdpfx Aoh Ar Dusc Tsg 8 mm at the smallest inner diameter of 300 mm (1.5 x top roll) Edge bending performance data 8 mm at the smallest inner diameter of 1000 mm (5 x top roll) 6 mm at the smallest inner diameter of 300 mm (1.5 x top roll) All bending capacities are calculated based on a yield strength of 250 N/mm2 Material (ST 37 - ST 42 structural steel)

Condition: new, Ostas 4-Roller Plate Bending Machine 4R OHS 3070 x 275 Hydraulic Side Roller Adjustment 3 Digital Displays Hydraulic Drop-End Hardened Rollers Cone Bending Device Separate Control Console Roll Length: 3070 mm Bsdpfx Acsxrduyj Tedg Top Roller Diameter: 275 mm Side Roller Diameter: 220 mm Total Motor Power: 16.5 kW Weight: 10,300 kg Dimensions (mm): 5900 x 1750 x 1860 (L x W x H) Bending Performance Data 12 mm at minimum inner diameter (5 x top roller) 10 mm at minimum inner diameter (1.5 x top roller) Pre-bending Performance Data 10 mm at minimum inner diameter (5 x top roller) 8 mm at minimum inner diameter (1.5 x top roller) All bending capacities are calculated based on a yield strength of 250 N/mm2 Material (ST 37 – ST 42 structural steel) The images shown are for illustration purposes only.

Condition: new, Ostas 4-Roller Plate Bending Machine 4R OHS 3070 x 250 Hydraulic side roll adjustment 3 digital displays Hydraulic drop-end bearing Bedpfx Asyaqmajc Tedg Hardened rolls Cone bending device Separate control panel Roll length: 3070 mm Top roll diameter: 250 mm Side roll diameter: 200 mm Total motor power: 7.5 + 1.5 kW Weight: 9800 kg Dimensions (mm): 5050 x 1550 x 1470 (L x W x H) Bending performance data 9 mm at minimum inner diameter (5 x top roll) 7 mm at minimum inner diameter (1.5 x top roll) Pre-bending performance data 7 mm at minimum inner diameter (5 x top roll) 5 mm at minimum inner diameter (1.5 x top roll) All bending capacities are based on a yield strength of 250 N/mm2 Material: (ST 37 – ST 42 structural steel)

Condition: new, Ostas 4-Roller Plate Rolling Machine 4R OHS 2570 x 250 Hydraulic Side Roll Adjustment 3 Digital Readouts Hydraulic Drop-End Hardened Rolls Conical Bending Device Separate Control Panel Roll Length: 2570 mm Bsdpfxexrdcds Ac Tsdg Top Roll Diameter: 250 mm Side Roll Diameter: 200 mm Total Motor Power: 7.5+1.5 kW Weight: 6300 kg Dimensions (mm): 4550 x 1550 x 1470 (L x W x H) Bending Performance Data 10 mm at minimum inner diameter (5 x top roll) 8 mm at minimum inner diameter (1.5 x top roll) Pre-bending Performance Data 8 mm at minimum inner diameter (5 x top roll) 6 mm at minimum inner diameter (1.5 x top roll) All bending capacities are calculated based on 250 N/mm² yield strength Material: ST 37 – ST 42 structural steel The images shown are for illustration purposes only.

Condition: new, Ostas 4-Roller Plate Bending Machine 4R OHS 1570 x 150 Hydraulic side roller adjustment 3 digital displays Hydraulic drop-end Hardened rollers Device for conical bending Separate control panel Roll length: 1570 mm Top roller diameter: 150 mm Side roller diameter: 130 mm Total motor power: 4+3 kW Weight: 2,470 kg Dimensions (mm): 3350 x 1200 x 1210 (L x W x H) Bending performance data 6 mm at minimum internal diameter (5 x top roller) 4 mm at minimum internal diameter (1.5 x top roller) Pre-bending performance data 4 mm at minimum internal diameter (5 x top roller) 3 mm at minimum internal diameter (1.5 x top roller) All bending capacities are calculated on the basis of 250 N/mm² yield strength Bdjdjxrc Dtepfx Ac Tsg Material (ST 37 - ST 42 structural steel)

Condition: new, Ostas 4-Roll Plate Bending Machine 4R OHS 2570 x 275 Hydraulic Side Roll Positioning 3 Digital Displays Hydraulic Drop-End Hardened Rolls Bjdpfx Ajxrdn Hec Tedg Cone Bending Device Separate Control Console Roll Length: 2570 mm Top Roll Diameter: 275 mm Side Rolls Diameter: 220 mm Total Motor Power: 16.5 kW Weight: 9500 kg Dimensions (mm): 5350 x 1750 x 1950 (L x W x H) Bending Performance Data 16 mm at minimum inside diameter (5 x top roll) 12 mm at minimum inside diameter (1.5 x top roll) Pre-bending Performance Data 12 mm at minimum inside diameter (5 x top roll) 10 mm at minimum inside diameter (1.5 x top roll) All bending capacities are based on 250 N/mm2 yield strength Material (ST 37 – ST 42 structural steel) The images shown are for illustration purposes only.

Condition: new, Ostas 4-roll plate bending machine 4R OHS 3070 x 320 Hydraulic side roll adjustment 3 digital displays Hydraulic drop-end bearing Hardened rolls Conical bending device Bdsdsxrdxfopfx Ac Tsg Separate control panel Roll length: 3070 mm Top roll diameter: 320 mm Side roll diameter: 240 mm Total motor power: 20 kW Weight: 13,050 kg Dimensions (mm): 5900 x 1850 x 2050 (L x W x H) Bending Performance Data 16 mm at minimum inside diameter (5 x top roll) 12 mm at minimum inside diameter (1.5 x top roll) Pre-bending Performance Data 12 mm at minimum inside diameter (5 x top roll) 10 mm at minimum inside diameter (1.5 x top roll) All bending capacities are calculated based on a yield strength of 250 N/mm2 Material (ST 37 – ST 42 structural steel) The pictures shown are for reference only.

Condition: good (used), Year of construction: 2011, functionality: fully functional, machine/vehicle number: 104605-104645, input voltage: 400 V, total width: 1,500 mm, total length: 4,500 mm, total height: 2,820 mm, type of input current: three-phase, Fortuna Primus K4 – 4-row roll divider – rounder + depositor + GEK, year of manufacture 2011 Dough divider & rounder Bdsdpfx Aoy St U Ssc Tjg Condition: fully functional, directly from ongoing operation Application: round rolls, e.g., Kaiser rolls, braided rolls, salt rolls, wheat & mixed doughs • Weight range: approx. 40-110/120 g • Hourly output: approx. 4,800 pieces/hour • Rounding chamber height: approx. 10–35 • Rounding speed: scale 0–30 • Hopper volume: 20–25 kg • Dough yield: TA 160–165 • Connection power: approx. 1.5 kW • Machine weight: 650–700 kg • Depositor: for 60 × 80 cm trays (58–78) _____ Equipment • Fortuna Primus K head machine • 4 rows • GEK pre-fermentation cabinet matching the line • Rounding/stamping sets: Kaiser rolls, braided rolls, salt rolls • Complete depositor • Immediately ready for operation • In use until recently • Clean, well-maintained, regularly serviced • No known defects • Electronics modernized (new display) INSPECTION and TRIAL RUN possible (only) by appointment Freight possible, fully assembled with a jumbo truck (L/W/H = approx. 4,500 mm x 1,500 mm x 2,820 mm)

Condition: new, neu ca. 10 Wochen ab Auftrags Türkei 3400 € 1270 mm 1.2 mm 68 mm 1.5 kW 1610 mm 700 mm 1160 mm 385 kg 3 Walzen asymmetric rolls - prebending longitudinal grooves in lower and lateral roll Infeed of the lower roller by a central lever - with gear reduction machine stand Bdodoynndropfx Ac Tsg user manual in GERMAN orENGLISH

Condition: used, roller (top) diameter: 160 mm, working width: 1,050 mm, sheet thickness (max.): 10 mm, Epart Motorized Cylinder 1050 x 10 mm Brand: Epart Type: Motorized Capacity: 1050mm x 10mm Upper roller diameter: 160mm Motorized rear roller Bsdpfx Acjvlxyzo Tedg Roller extension to mount rollers Pedal operated Perimeter security by limit switch Front roller separation by steering wheel

Condition: used, functionality: fully functional, actuation type: hydraulic, roller (top) diameter: 420 mm, sheet thickness (max.): 25 mm, total length: 3,100 mm, Hydraulic cylinder Brand: Casanova Bending length: 3,100 mm Maximum bending thickness: 25 mm Bdsdsydk D Hspfx Ac Tsg Top roller diameter: 420 mm The side rollers are raised parallel, without inclination. New control and command panel, installed and modified in 2003. Equipped with hydraulic flag and hydraulic side table. Pit dimensions: - 200x6800 mm - 555 mm depth

Condition: good (used), functionality: fully functional, Year of construction: 1980, 2500 mm x 340 Ømm top roller Rolling capacity: 2500 x 23 mm (5 x top roller diameter) Bdsdeyz Acwepfx Ac Teg Max. sheet thickness: 2500 x 15 mm Equipped with top crane and side support

Condition: new, Solid feed for commercial needs Reinforced machine cast stand parts. With frequency converter and digital speed display Bodpfx Asvrv Ivsc Tsdg Technical data: Number of feed rollers 4 Dimensions of the feed rollers 120x60 mm Speed ??continuously 2-22 m/min Motor output power S1 400W / 400V Weight approx. 70 kg

Condition: used, Year of construction: 1989, Schäfer SVRM 3500/12 - CNC 4-Roller Plate Bending Machine - Siemens CNC control with joystick for roller positioning and digital display (upgraded in 2006) - Hydraulic tilting of the top roller via control panel - Rollers made of hardened material with a strength of 900 N/mm² - Year of manufacture: 1989 Bdedsylyh Dspfx Ac Teg Technical Data - Max. sheet width: 3500 mm - Roller barrel length: 3550 mm - Max. sheet thickness (bending): 12 mm - Max. sheet thickness (pre-bending) 4xS/3xS: 8 / 6 mm - Max. yield limit of sheets at 20% cold work hardening: 380 N/mm² - Top & bottom roller diameter: 360 mm - Side roller diameter: 290 mm - Smallest achievable bending radius: 220 mm - Feed speed, bottom roller: 200 mm/min - Feed speed, side rollers: 700 mm/min - Total installed power: 22 kW - Electrical system: 380 V / 50 Hz / 3 Ph - Space requirements including control, hydraulics & roller conveyor (WxHxD): approx. 7900 x 3300 x 4600 mm - Pit depth: 900 mm - Machine weight: 21,100 kg

Condition: new, Year of construction: 2023, sheet width 1540 mm plate thickness 4 mm upper roll diameter 110 mm diameter of lower rolls 110 mm bending roll diameter 110 mm total power requirement 1,1 kW weight of the machine ca. 0,9 t dimensions of the machine ca. 2,5x0,6x1,1 m New machine Cone bending equipment, hardened and ground rollers, motorized bending roller stationary control panel, digital display bending roller right and left, Bdsdpfsvx Uvxjx Ac Tog digital display bottom roller