Beli Minini Mesin Gerinda Permukaan bekas (77.184)

Kondisi: bekas, Tahun pembuatan: 1987, Schleiflaenge-1250-mm-Kopie Dcjdpfx Aey Ezz Toc Tsi

Kondisi: diremaj di bengkel (bekas), Tahun pembuatan: 1978, Fungsionalitas: berfungsi sepenuhnya, nomor mesin/kendaraan: 1025, en Dcjdpfsy D I Idox Ac Tsi

Kondisi: baik (bekas), Tahun pembuatan: 1984, Fungsionalitas: berfungsi sepenuhnya, tischgroesse-2000x650-zubehoer Dedpfjyr Iqmsx Ac Tjci

Kondisi: baik (bekas), LOCHDURCHMESSER: 1–100 mm LOCHTIEFE: 230–350 mm WERKSTÜCKDURCHMESSER: 360–500 mm Dcsdpfx Aewf Hgboc Tei WERKSTÜCKLÄNGE: 850–1000 mm WERKSTÜCKKOPF-NEIGUNG: 15° WERKSTÜCKGEWICHT: kg SCHLEIFSCHEIBENDREHZAHL: 18.000–24.000 U/min WERKSTÜCKSPINDEL-DREHZAHL: 140–1.120 U/min LEISTUNG: kW GEWICHT: 4,5 t

Kondisi: bekas, Jung F 50 Mesin Gerinda Permukaan Kondisi: Bekas Data Teknis Panjang penggerindaan: 500 mm Lebar penggerindaan: 200 mm Tinggi penggerindaan hingga tengah spindle: 285 mm Ukuran meja: 700 x 200 mm Kecepatan spindle: sekitar 3000 rpm Batu gerinda: 225 x 20 x 51 mm Pengaturan: manual dengan handwheel Gerak cepat Perangkat dresser Dsdpoyuy Eujfx Ac Tjci Dimensi P / L / T: sekitar 1850 mm / 1300 mm / 1750 mm Berat: sekitar 1400 kg

Kondisi: siap digunakan (bekas), Tahun pembuatan: 1999, Fungsionalitas: berfungsi sepenuhnya, nomor mesin/kendaraan: 14556, diameter roda gerinda: 400 mm, jarak pergerakan sumbu X: 900 mm, jarak lintasan sumbu Y: 550 mm, jarak gerak sumbu Z: 360 mm, kecepatan spindle penggilingan: 3.400 rpm, RINCIAN TEKNIS Perjalanan sumbu X: 900 mm Perjalanan sumbu Y: 550 mm Perjalanan sumbu Z: 360 mm Lebar meja: 790 mm Kedalaman meja: 380 mm Dsdpfoyuamxex Ac Teci Diameter maksimum batu gerinda: 400 mm Kecepatan putar spindle maksimum: 3.400 rpm PERLENGKAPAN Sertifikasi CE Dokumentasi

Tahun pembuatan: 2018, Kondisi: siap digunakan (bekas), - GEBRAUCHT - FLACHSCHLEIFMASCHINE MAX. SCHLEIFLÄNGE: 600 mm MAX. SCHLEIFBREITE: 400 mm LÄNGSVERFAHRWEG: 750 mm QUERVERFAHRWEG: 340 mm TISCHGRÖSSE: 650 x 400 mm Djdpfx Acsyry R Se Tjci MAX. ZULÄSSIGE BELADUNG: 420 kg MAGNETSPANNPLATTE: 600 x 400 mm SCHLEIFSCHEIBENABMESSUNGEN: 355 x 38 x 127 mm SCHLEIFSCHEIBENDREHZAHL: 1.500 U/min MOTORLEISTUNG: 3,7 kW GEWICHT: 2.900 kg GESAMTABMESSUNGEN: 2.725 x 2.205 x 1.761 mm ZUBEHÖR: Papierfilter

Tahun pembuatan: 1964, Kondisi: sangat baik (bekas), Description to follow! Dedpfxoytg U Te Ac Toci

Kondisi: siap digunakan (bekas), Tahun pembuatan: 2021, Fungsionalitas: berfungsi sepenuhnya, panjang penggilingan: 1.600 mm, lebar penggilingan: 500 mm, berat benda kerja (maks.): 900 kg, diameter roda gerinda: 355 mm, gerak cepat sumbu X: 1 m/menit, kecepatan perjalanan (maks.): 25 mm/menit, TECHNICAL DETAILS Table size: 500 x 1,600 mm Maximum grinding area: 500 x 1,600 mm Distance from spindle center to worktable (max.): 600 mm Load capacity (with magnetic chuck): 900 kg Axes Parameters Longitudinal feed rate: 5–25 m/min Cross rapid traverse (X-axis): 50–1,000 mm/min Cross feed, incremental: 1–20 mm/stroke Cross manual feed (MPG): 0.005 mm/click Vertical rapid traverse (Z-axis): 50–500 mm/min Vertical automatic feed: 0.005–0.04 mm/stroke Vertical manual feed (MPG): 0.005 mm/click Grinding Wheel Dimensions (outer diameter x width x bore): 355 x 20~50 x 127 mm Spindle speed: 1,440 rpm Drive Power Spindle motor: 7.5 kW Hydraulic pump motor: 3 kW Servo motor for cross feed: 0.5 kW Servo motor for vertical feed: 2 kW Coolant pump: 0.125 kW Lubrication pump: 0.06 kW Total connected load: 14 kVA MACHINE DETAILS Dimensions & Weight Required installation area: 7,120 x 2,550 mm Height: 2,700 mm Machine weight: approx. 6,000 kg EQUIPMENT PLC + HMI automatic grinding control Djdpfx Aeyymkcoc Teci Integrated control for magnetic chuck Coolant tank Balancing arbor Grinding wheel flange and puller Grinding wheel dresser stand MPG handwheels for Y/Z-axis Operating manual Splash guard Standard grinding wheel Levelling wedges and bolts

Kondisi: baik (bekas), Tahun pembuatan: 1993, Mesin gerinda permukaan ELB Tahun: 1993 Ukuran meja magnetik: 1500x550 mm Dengan turun otomatis Dengan alat pemotong batu gerinda Dsdpfx Acsygtiwo Tsci Tangki pendingin tipe pita kertas Banyak batu gerinda

Kondisi: seperti baru (mesin pameran), Tahun pembuatan: 2025, GT 25 - The OPTIMUM Premium NC Grinding Machine with Siemens Touch Screen. • Electromagnetic clamping plate for securing the workpiece with automatic demagnetization function • High-quality spindle with precision tapered roller bearings • Hardened and ground table guideways • Turcite-B coated counter-guides for high wear resistance and low friction • Grinding spindle with high-precision bearings • Grinding wheel can be dressed directly on the machine with an integrated dressing device • Digital position display • Machine base made from robust, torsion-resistant cast iron for maximum rigidity and stability • Guideways for longitudinal, cross and vertical movements are backlash-free and self-centering, designed as V- and flat guides • Precision ball screw spindles • Central lubrication for guideways and feed screws • All flat guideways are finely scraped, ensuring maximum precision in all manual movements • Safety electronics in 24 V DC • Large, decoupled handwheels on all three axes • Hydraulic lines according to DIN EN 853 • Grinding accuracy: 0.005 mm • Corundum grinding wheel, grit 46, suitable for all common steels • Swiveling operating panel for significantly easier operation • Separate hydraulic unit with heat exchanger, prevents vibrations and thermal stress • Dual-channel safety electronics • Grinding table splash guard • EMC filter class • Equipped with IE3 motor – significantly lower energy consumption for substantial cost savings Technical Data: Dimensions and Weights Length approx. 2300 mm Width/Depth approx. 1600 mm Height approx. 1675 mm Weight approx. 1700 kg Electrical Data Total connected load 3 kW Connection voltage 400 V Phases 3 Ph Current type AC Mains frequency 50 Hz Surface Grinding Table Length 254 mm Width 508 mm Grinding Wheel(s) Outside diameter 200 mm Width 20 mm Bore 31.75 mm Peripheral speed 33 m/s Spindle Speed 2850 rpm Runout accuracy 0.005 mm X-Axis Feed speed 5 – 25 m/min PU 1 Scope of Delivery Quantity unit: piece Packaging unit: 1 Digital position display Coolant system Balancing arbor Grinding wheel, grit 46 Diamond dresser Operating tools Manual oil pump LED lamp Electromagnetic clamping plate Demagnetization function Equipment Clamping plate: Electromagnet Table enclosure: splash guard Demagnetizer: automatic Parallel dressing device Coolant system: 40 W Dsdpfxsymdwfs Ac Teci Work light: LED lamp Leveling feet

Kondisi: seperti baru (mesin pameran), Tahun pembuatan: 2025, GT 40 – The OPTIMUM Premium NC Surface Grinder with Siemens Touchscreen. • Electromagnetic chuck for securing the workpiece, featuring automatic demagnetization function • High-quality spindle with precision tapered roller bearings • Hardened and ground table guideways • Turcite-B coated counterguides for high wear resistance and low friction • Grinding spindle equipped with high-precision bearings • The grinding wheel can be dressed directly on the machine using the integrated dressing device • Digital position display • Machine base made of robust, torsion-resistant cast iron for maximum rigidity and stability • The longitudinal, cross, and vertical axis guideways are backlash-free and self-centering, designed as V- and flat ways • Precision ball screw drives • Central lubrication for guideways and leadscrews • All flat guideways are finely scraped to guarantee maximum manual movement precision • Safety electrics using 24V DC • Large, decoupled handwheels in all three axes • Hydraulic lines conforming to DIN EN 853 • Grinding accuracy: 0.005 mm • Corundum grinding wheel, grit 46, suitable for all common steels • Swiveling control panel significantly eases operation • Separate hydraulic unit with heat exchanger, eliminates vibration and thermal load • Dual-channel safety electronics • Grinding table splash guard • EMC filter class • Equipped with IE3 motor – significantly reduces energy consumption, resulting in notable cost savings Dimensions and Weights Length approx. 3,600 mm Width/Depth approx. 2,400 mm Height approx. 1,900 mm Weight approx. 3,600 kg Electrical Data Total connected load: 7.5 kW Supply voltage: 400 V Mains frequency: 50 Hz Surface Grinding Table Clamping area length: 400 mm Clamping area width: 800 mm Grinding Wheel(s) Outer diameter: 350 mm Width: 40 mm Bore: 127 mm Peripheral speed: 27 m/s Spindle Speed: 1,450 rpm Runout accuracy: 0.005 mm X-Axis Feed speed: 5 – 25 m/min Included Equipment Digital position display Coolant system Balancing arbor Dodpfxjymduqo Ac Tjci Grit 46 grinding wheel Diamond dresser Operating tools Manual oil pump LED lamp Electromagnetic chuck Demagnetization function Features Electromagnetic chuck Table splash guard enclosure Demagnetization device Parallel dressing device ✔ Coolant system 125 W Work lamp LED Leveling feet ✔

Kondisi: seperti baru (mesin pameran), Tahun pembuatan: 2025, GT 30 – The OPTIMUM Premium NC Grinding Machine with Siemens Touch Screen. • Electromagnetic chuck for securing the workpiece with automatic demagnetization function • High-quality spindle with precision tapered roller bearings • Hardened and ground table guideways Dedeymdtyjpfx Ac Tsci • Turcite-B coated counter guides for high wear resistance and low friction • Grinding spindle fitted with high-precision bearings • Grinding wheel can be dressed directly on the machine using an integrated dressing device • Digital position display • Machine base made of robust, torsion-resistant cast iron for maximum rigidity and stability • Longitudinal, cross and vertical axis guideways are backlash-free and self-centering in V- and flat guide configuration • Precision ball screws • Central lubrication for guideways and feed screws • All flat guideways are hand-scraped, guaranteeing the highest precision for all manual movements • Safety electrics in 24 V DC • Large, decoupled handwheels on all three axes • Hydraulic lines according to DIN EN 853 • Grinding accuracy: 0.005 mm • Aluminium oxide grinding wheel, grit 46, suitable for all standard steels • Pivoting control panel significantly facilitates operation • Separate hydraulic unit with heat exchanger minimizes vibration and thermal load • Dual-channel safety electronics • Splash guard for grinding table • EMC filter class • Fitted with IE3 motor – significantly lower energy consumption for substantial cost savings Dimensions and Weights Length approx. 3200 mm Width/depth approx. 2200 mm Height approx. 2100 mm Weight approx. 3000 kg Electrical Data Total connected load: 6.5 kW Connected voltage: 400 V Mains frequency: 50 Hz Surface grinding table Clamping area length: 300 mm Clamping area width: 600 mm Grinding Wheel(s) Outer diameter: 350 mm Width: 40 mm Bore: 127 mm Circumferential speed: 27 m/s Spindle Speed: 1450 rpm Run-out accuracy: 0.005 mm X-Axis Feed speed: 5 – 25 m/min Scope of Delivery Unit: piece Packing unit: 1 Digital position display Coolant device Balancing arbor Grinding wheel, grit 46 Diamond dresser Operating tools Manual oil pump LED lamp Electromagnetic chuck Demagnetization function Equipment Electromagnetic chuck Splash guard with table enclosure Automatic demagnetization unit Parallel dressing device ✔ Coolant system 125 W Work light, LED lamp Levelling feet ✔

Kondisi: belum diuji (bekas), Okamoto surface grinding machine ACC-12.24DX for sale The machine cannot be tested by us, as it requires a 60 Hz power supply. Visually, the machine is in good condition. A new grinding wheel is included in the offer. Technical data: Voltage: 230/460 V Frequency: 60 Hz Phase: 3 Power: 7.5 kVA Control voltage AC: 100 V Control voltage DC: 12–24 V Clamping surface: 30 x 67 cm Grinding wheel diameter: 30 cm Bolt circle diameter: 7.5 cm Upon request and for an additional charge, the machine can be loaded onto a truck and transport can be organized throughout Europe. Prices are subject to VAT. Dsdpfxonzhwwe Ac Tjci Inspection possible by appointment. Please contact us; our team will be pleased to assist you. Trade-in or exchange possible! Machine purchase / sale PURCHASE / SALE OF PRODUCTION & METALWORKING MACHINERY AND MORE. Are you looking for a high-quality yet affordable metalworking machine for your production? Or do you want to sell yours? For more information or to contact us, please visit our website.

Kondisi: bekas, Tahun pembuatan: 1980, Technical details: Grinding length: 600 mm Grinding width: 300 mm Total power requirement: 7.5 kW Spindle speed: 0-3000 rpm Grinding spindle motor: 7.5 kW Grinding wheel diameter: 300 mm Grinding wheel dimensions: 76 x 20 mm Magnetic table surface grinding machine Dsdpfx Aoyk Utfjc Toci

Kondisi: Pembawa suku cadang rusak (bekas), Tahun pembuatan: 2007, Fungsionalitas: tidak berfungsi, panjang penggilingan: 3.150 mm, lebar penggilingan: 800 mm, beban meja: 6.000 kg, daya motor spindle penggiling: 22.000 W, tinggi benda kerja (maks.): 650 mm, Tanpa harga minimum – penjualan dijamin kepada penawar tertinggi! DETAIL TEKNIS Panjang penggerindaan: 3.150 mm Lebar penggerindaan: 800 mm Ketinggian benda kerja maks.: 650 mm Ukuran bidang meja: 3.150 x 600 mm Ukuran pelat magnet: 3.000 x 600 mm Ukuran batu gerinda: 450 x 100 x 127 mm Daya dukung meja maks.: 6 t DETAIL MESIN Kontrol: SIEMENS 840D Dsdpjylk E Hjfx Ac Teci Total kebutuhan daya: 70,6 kW Daya motor spindle: 22 kW Dimensi & Berat Ruang yang dibutuhkan: sekitar 11 x 3 x 2,4 m Berat mesin: sekitar 15 t PERLENGKAPAN Unit pendingin 2.500 l Pengaturan daya magnet Sistem penyeimbang semi-otomatis Catatan: Kontrol dapat menyala, tetapi perangkat lunak penggilingan MININI tidak memuat karena alasan yang tidak diketahui. Perangkat keras kontrol telah diperiksa dan dalam kondisi baik. File cadangan tersedia.

Kondisi: siap digunakan (bekas), Tahun pembuatan: 2006, Fungsionalitas: berfungsi sepenuhnya, nomor mesin/kendaraan: 2449-01, lebar penggilingan: 1.350 mm, tinggi penggerindaan: 150 mm, kecepatan pemakanan sumbu X: 12 m/menit, diameter roda gerinda: 1.380 mm, RINCIAN TEKNIS Dimensi benda kerja (Panjang x Lebar) min.: 30 x 30 mm Dcedpfeyx Hhxsx Ac Tji Dimensi benda kerja (Lebar x Tinggi) maks.: 1.350 x 150 mm Dimensi sabuk amplas: 1.380 x 1.900 mm Diameter cakram: 1.380 mm Kecepatan unit sabuk amplas: 8-22 m/dtk Kecepatan unit cakram: 10-22 m/dtk Kecepatan feeding (kontrol frekuensi): 2-12 m/menit RINCIAN MESIN Daya listrik Motor feeding (kontrol frekuensi): 2,6 kW Sabuk amplas (W): 18,5 kW Cakram (RD): 12,9 kW Koneksi listrik: 400 V Frekuensi: 50 Hz Arus kontrol: 110 A PERLENGKAPAN Unit cakram (RD) dengan cakram abrasive non-woven 2 unit sabuk amplas (W) sebelum dan sesudah unit cakram

Kondisi: bekas, Tahun pembuatan: 2007, translation Dedpfx Aoykmqvoc Tsci

Tahun pembuatan: 2015, Kondisi: bekas, Workpiece diameter: 300 mm Workpiece weight: 999 kg Dcsdpfx Aoxflclsc Toi Workpiece height: 145 mm Equipment: - Digital display for vertical axis - Automatic infeed - Programmable automatic end shut-off - Grinding spindle drive with infinitely variable electronic speed control - Infinitely variable cross-feed and table rotation - 24V magnetic chuck, 300 mm - Various safety devices, e.g. safety hood monitoring, operating status indication via signal light - Lubrication oil level monitoring - The machine was completely overhauled in 2015, including replacement of all electrical systems to PLC control and 24V control voltage - Paper band filter system, specifically adapted for this machine The following works have now also been carried out: - Replacement of bellows and belts - Grinding spindle newly mounted - Grinding carriage bed and rotary table bed hand-scraped to restore improved and more precise running characteristics - Grinding carriage and cross table lifted off machine body, all guideways cleaned, lubrication checked - Various wear parts, such as rubber caps and switch elements replaced - Thorough functional inspection - Infeed arm modernization - Paintwork touch-ups, machine colour: light grey RAL 7035 and RAL 7012

Tahun pembuatan: 1994, Kondisi: bekas, en Dedpfxexbtl Te Ac Toci

Kondisi: bekas, Hersteller: BLOHM Typ: Simplex 5 Tischgröße: 900 x 300 mm Dcodpfx Acsvtyxuo Tsi Arbeitsbereich: 600 x 300 mm Ohne Magnetspannplatte!

Kondisi: baru, Fungsionalitas: berfungsi sepenuhnya, panjang penggilingan: 510 mm, lebar penggilingan: 250 mm, Reduced slip-stick effect thanks to x and y-axis guides with plastic-coated surfaces Longitudinal table guide is flat, while the transverse guide is triangular Radial and axial forces are evenly distributed across special backlash-free bearings in the grinding spindle head Separate hydraulic unit with heat exchanger prevents vibrations and overheating High stability due to ribbing and robust, dimensionally stable walls Digital control for automatic vertical feed via servomotor Hydraulic system ensures smooth table movement, even under heavy loads Rapid positioning to the workpiece height with fast traverse, automatic lift after program completion Adjustable longitudinal and vertical table feed using end stops PLC models equipped with SIEMENS PLC controllers with touch screen Technical Specifications Table clamping surface width 510 mm Table clamping surface depth 250 mm T-slots (number / width) 1 / 14 mm Electromagnetic table size 250 x 500 mm Longitudinal travel (x) 560 mm Dedpfeyt Hzmox Ac Teci Cross travel (y) 275 mm Maximum spindle axis to table distance 450 mm Maximum table load 180 kg Grinding wheel size 200 x 20 x 31.75 mm Hydraulic table feed speed 5 - 25 m/min Grinding spindle speed 2850 rpm Grinding spindle motor power 2.2 kW Hydraulic pump motor power 0.75 kW Vertical feed motor power 0.5 kW Total motor power 3.45 kW Voltage 400 V Dimensions (width) 1900 mm Dimensions (depth) 2050 mm Dimensions (height) 1840 mm Weight approx. 1750 kg Cross feed (Y) Automatic cross feed 0.5 - 8 mm/stroke Rapid cross feed 990 mm/min Cross feed per handwheel revolution 4 mm/rev Handwheel graduation (Y) 0.02 mm Vertical feed (Z) Automatic vertical feed 0.005 / 0.01 / 0.02 / 0.03 / 0.04 / 0.05 mm/stroke Rapid vertical feed 480 mm/min Vertical feed per handwheel revolution 2 mm Handwheel graduation (Z) 0.005 mm

Kondisi: baru, Fungsionalitas: berfungsi sepenuhnya, panjang penggilingan: 304 mm, lebar penggilingan: 152 mm, MSG 1530 BERNARDO Surface Grinder Compact surface grinder: longitudinal, cross, and vertical feed are fully manual. Low-vibration spindle operation thanks to high-quality special bearings. Indispensable for machining smaller parts and during rapid grinding operations. Longitudinal table movement via a combination of V-type and flat guideways; cross table and vertical wheel feed are realized by dove-tail guideways. Manual central lubrication for all guideways. All main components such as column, base, and carriage are made from high-quality cast iron. Technical Specifications Table clamping surface width: 304 mm Table clamping surface depth: 152 mm Longitudinal travel (X): 340 mm Cross travel (Y): 170 mm Max spindle center to table: 210 mm Max table load: 30 kg Grinding wheel size: 180 x 13 x 31.75 mm Spindle speed: 2,800 rpm Grinding spindle motor power: 0.55 kW Voltage: 230 V Dimensions (W x D x H): 1100 x 760 x 880 mm Weight approx.: 210 kg Manual Cross Feed (Y) Manual cross feed: 2.54 mm/rev Handwheel graduation (Y): 0.02 mm Manual Vertical Feed (Z) Manual vertical feed: 1.25 mm/rev Dodpfeyt Hycox Ac Toci Handwheel graduation (Z): 0.025 mm Scope of Delivery Basic tools Fixed magnetic chuck Wheel flange Grinding wheel Legally required safety guards Complete operation manual (DTR) in Polish CE Certificate 24-month warranty for all, with no additional costs

Kondisi: sangat baik (bekas), Tahun pembuatan: 1996, JUNG JF 600 Surface Grinding Machine Jung JF 600 Year of Manufacture 1996 Overhauled in 2018 Excellent CONDITION The machine comes from the training workshop of a renowned German mechanical engineering company. Technical Data: Year of manufacture: 1993/2018 Table length: 600 mm Table width: 250 mm Axis movement: Longitudinal travel (X-axis): 600 mm Cross travel (Z-axis): 280 mm Maximum distance between table and spindle center: 500 mm Grinding length: 600 mm Table speed: Stepless from: 1 m/min up to: 24 m/min Creep feed: from: 0.03 m/min up to: 0.40 m/min Automatic cross feed: Stepless from: 0.010 mm/min up to: 10000 mm/min Connection 50 Hz 3x: 380 Volt Grinding spindle motor: 9.5 kW Total power requirement: 13 kVA Djdpfsyxdalsx Ac Teci Machine weight approx.: 2500 kg Machine dimensions: Length: 2910 mm Width: 2320 mm Height: 1840 mm Various accessories: Coolant system About the machine: Offered here is a JUNG JF 600 surface grinding machine. This universal surface grinder is in very good original condition. It comes from a facility where it was used only occasionally for training purposes. The control is very easy to operate. With a grinding travel of 600 mm on the longitudinal axis and 300 mm on the cross axis, it is ideally suited for toolmaking, fixture construction, and small batch production. This model line is characterized by its comprehensive standard equipment and ease of use. The robust spindle head design and double V-guideways on both the longitudinal and cross axes ensure lasting precision. The intuitive operation of the control elements simplifies handling and significantly increases productivity. The guideways are automatically lubricated via the central lubrication system. The Jung has been mechanically and electrically tested by us. Take advantage of the opportunity to view and test the Jung under power at our facility. You will find further surface grinding machines from well-known manufacturers on our website.

Kondisi: siap digunakan (bekas), Tahun pembuatan: 2002, Fungsionalitas: berfungsi sepenuhnya, nomor mesin/kendaraan: 04374, panjang penggilingan: 1.000 mm, lebar penggilingan: 700 mm, diameter roda gerinda: 406 mm, beban meja: 1.000 kg, model controller: SIEMENS SINUMERIK 840 D, 1 Dsdpfx Acjyhnv Ue Teci