Gieseking Sistem Za Ravnanje Cevi nakup rabljenega (86.351)

Stanje: zelo dobro (rabljeno), emtest / AMETEK Automotive EMC Test System incl. Laptop & Software Manufacturer: emtest / AMETEK Type: Automotive EMC / On-board Network Test System Configuration: Mobile 19" industrial cabinet For sale is a professional test and simulation system from emtest / AMETEK for industrial applications in the fields of automotive, electronics testing, on-board network simulation, and EMC/EMI test engineering. The system is supplied with a laptop installed with control and test software, making it suitable for professional laboratory, development, and test bench applications. Iiedpfx Abjy Rlbhs Aeb The system consists of several integrated test modules, fan units, and various power, control, and interface components. Visible identifiable components: Module 1: emtest AutoWave Module 2: emtest VDS 200Q Display designation: VDS 200Q100.2 Function per display: Voltage Drop Simulator Serial number per display: SWN 001638 AutoWave display info: Version 8.03.05 Out: 2 / In: 0 VDS 200Q display info: DC supply waveforms Firmware: V2.02.00 Generator: V2.01.01 Additional model designation per documentation: VDS 200Q100.2-208 Connections / Interfaces: Ethernet IEEE 488 USB VDS Frame Bus In / Frame Bus Out Analog In AutoWave CH1 / CH2 / CH4 0–10 V connection DC output / output terminals CEE power connection Emergency stop switch Features: Mobile industrial / 19" switch cabinet Multiple integrated fan units Front control and connection panels Rear power and interface connections Side emergency stop switch Industrial-grade design for laboratory, development, and test bench applications Possible application areas: Automotive test engineering On-board network simulation Voltage drop simulation Electronics and component testing EMC/EMI laboratory Research and development Quality assurance Test bench engineering Technical notes: Four-quadrant voltage drop simulator Suitable for automotive voltage profile testing Supports various automotive test standards such as LV 124, LV 148, ISO 7637-2, ISO 16750, and comparable norms Output range per documentation: -20 V to +80 V Bandwidth up to 250 kHz Condition: Used device with age- and use-related signs of wear. Visual condition as shown in images. Device powers on, displays are active. A full technical function test under load has not been performed. Dimensions & weight: Dimensions and weight have not been precisely determined. Due to the mobile industrial cabinet design, an industrial-level weight should be expected. Exact dimensions and weights can be measured if required. Scope of delivery: emtest / AMETEK test system in a mobile industrial cabinet Laptop including installed control and test software AutoWave module VDS 200Q / VDS 200Q100.2 module Integrated fan and connection units Contents as shown in the images Notes: Inspection possible by appointment. Loading can be arranged. Commercial sale – sold without warranty. Subject to alterations and errors.

Stanje: novo, Leto izdelave: 2026, moč: 1,5 kW (2,04 KM), vhodna napetost: 400 V, skupna dolžina: 600 mm, skupna širina: 600 mm, skupna višina: 1.400 mm, skupna masa: 300 kg, pritisk: 9,8 letvica, kapaciteta rezervoarja: 50 l, trajanje garancije: 12 meseci, RK50U – Universal forming system for the production of meat sticks, jerky & sausage snacks The HydroShpriz RK50U is a powerful hydraulic filling and forming machine, designed for small to medium-sized producers starting with the production of meat sticks, salami snacks, pet food, kibbeh, fruit bars, and more. Ideal for dry-seasoned snacks without alginate or natural casings. Compact, robust, and user-friendly – the perfect entry-level solution with upgrade options via our trade-in program. Technical Data • Drive: hydraulic piston • Piston force: 94 kN • Power: 1.5 kW, 380 V, 50 Hz • Dimensions: 1050×550×950 mm • Weight: approx. 300 kg • Material: made entirely from stainless steel • Certification: CE-certified, suitable for continuous operation (8 hours) Equipment & Features • Gear filling system – for dense, tough mixes down to –2 °C • Multi-nozzle head: up to 25 shapes simultaneously • Round nozzle set: 8 mm to 22 mm diameter (sticks) • Flat nozzle set: 25–200 mm width, 3–5 mm height (jerky, strips) • Sausage filling set: for traditional casing sausages • Layering attachment: direct forming onto wire racks • Compatible with drying trolleys: 30 levels, 60 racks • Integrated timer dosing: accuracy ±8 % • 24 V remote signal connection: for automatic clipping machines (e.g. PolyClip, Compa) • Optional vacuum connection – for firmer texture and longer product shelf life Production Output • From 20 kg to 1,600 kg per 8 hours, depending on product, shape, and nozzle system Stock Availability ✔️ Immediately available through official distributors in: • Austria Isdpjmrpvyofx Ab Aeib • Poland • United Kingdom • Lithuania • Australia • South Africa • USA Worldwide shipping, product training & spare parts included.

Stanje: rabljeno, številka stroja/vozila: 008208, Pozicija 1: Formatna žaga – podajanje s sprednje strani HOLZMA-HPP 510/43/43 + HEE 33/22 Pozicija 2: Dvižna miza HOLZMA-HPP 510/43/43 + HEE 33/22 Iijdpfsx A Thkox Ab Aob

Stanje: rabljeno, številka stroja/vozila: 007816, Pozicija 1: Avtomatizirano skladišče BIESSE-SELCO SK 450 Pozicija 2: Krožna žaga za plošče z avtomatiziranim skladiščem BIESSE-SELCO SK 450 Iisdpfx Aewuufqsb Asb

Stanje: novo, Leto izdelave: 2023, Funkcionalnost: popolnoma funkcionalen, Drying system / dryer suitable for various materials such as powders, granulates, etc. - Control system for temperature regulation Iodpsqu R Nasfx Ab Aeib This machine is connected and ready for testing in our machinery hall.

Stanje: zelo dobro (rabljeno), Leto izdelave: 2008, vrsta upravljanja: CNC krmiljenje, proizvajalec krmilnikov: ESA TOUCH PANEL, Dolžina cevi (maks.): 4.000 mm, radij upogibanja (maks.): 180 mm, minimalni polmer upogibanja: 10 mm, skupna masa: 3.700 kg, skupna dolžina: 6.000 mm, skupna širina: 1.800 mm, skupna višina: 1.800 mm, Machine de cintrage de tubes Transfluid - DB630 A3 CNC MACH-ID 9616 Fabricant : Transfluid Type : DB630 A3 CNC Commande : ESA TOUCH PANEL Année de fabrication : 2008 Diamètre max. du produit : 30mm Diamètre min. du produit : 4mm Iisdsy N Rv Iopfx Ab Asb Épaisseur max. de paroi : 4mm Rayon de cintrage max. : 180mm Rayon de cintrage min. : 10mm Longueur de cintrage max. : 4000mm Cintrage 3D : Oui Nombre d’outils : 10,12,15,16,18,20,22,28 Longueur : 6000mm Largeur : 1800mm Hauteur : 1800mm Poids : 3700kg Veuillez noter : Les informations figurant sur cette page ont été fournies au mieux de nos connaissances et, dans la mesure du possible, obtenues auprès du fabricant. Les informations sont fournies de bonne foi, mais leur exactitude ne peut être garantie. Elles ne constituent donc ni une représentation ni une condition contractuelle. Nous vous recommandons de vérifier tous les détails importants.

Stanje: dober (rabljeno),

Stanje: zelo dobro (rabljeno), Funkcionalnost: popolnoma funkcionalen, Leto izdelave: 1989, Premer cevi (maks.): 42 mm, Dolžina cevi (maks.): 3.000 mm, radij upogibanja (maks.): 180 mm, debelina stene: 3 mm,

Stanje: zelo dobro (rabljeno), Leto izdelave: 2006, Premer cevi (maks.): 120 mm, Dolžina cevi (maks.): 3.000 mm, Debelina stene cevi (maks.): 6 mm, radij upogibanja (maks.): 200 mm, minimalni polmer upogibanja: 10 mm, skupna masa: 12.500 kg, skupna dolžina: 5.000 mm, skupna širina: 2.200 mm, moč: 12 kW (16,32 KM), Stroj za upogibanje cevi MEWAG - RB 120 A-Digi MACH-ID 9605 Proizvajalec: MEWAG Ijdpfey E Hu Eox Ab Aeib Tip: RB 120 A-Digi Leto izdelave: 2006 Maks. premer izdelka: 120 mm Min. premer izdelka: 10 mm Maks. debelina stene: 6 mm Maks. polmer upogibanja: 200 mm Min. polmer upogibanja: 10 mm Maks. dolžina upogibanja: 3000 mm 3D upogibanje: da Moč: 12 kW Število orodij: 8 Dolžina: 5000 mm Širina: 2200 mm Višina: 1 mm Teža: 12500 kg Prosimo, upoštevajte: Informacije na tej strani so bile navedene po najboljšem znanju z naše strani in, kjer je bilo mogoče, od proizvajalca. Podani podatki so v dobri veri, vendar natančnosti ni mogoče zagotoviti. Zato ne predstavljajo pogodbenih pogojev ali jamstev. Priporočamo, da preverite vse pomembne podrobnosti.

Leto izdelave: 2022, stanje: dober (rabljeno), Funkcionalnost: popolnoma funkcionalen, This is a drying and disinfection system for boots and shoes from manufacturer PHT, model HYGIfeet M5. The Hygifeet drying and disinfection system is an innovation for all staff rooms and changing areas. The system stores boots and shoes after use while simultaneously disinfecting and drying them. Disinfection is safely achieved through ozone, eliminating the need for chemicals. The simultaneous drying process uses warm air, which ensures a short drying time. The ozone-warm air mixture is only released at the valve heads when boots are placed on them. The valve heads are ergonomically designed for optimal air circulation. Warm, dry boots enhance your employees’ comfort and, thanks to disinfection, help prevent illness. The device has been inspected by our in-house workshop and is fully functional. The stated price is net plus 19% VAT. OUR USED EQUIPMENT SERVICE FOR YOU: - 6 months warranty on all electrical parts - High-quality branded machines at fair prices - Professional overhaul/inspection & expert cleaning - Tested & fully functional – or your money back - Flexible choice of shipping or self-collection Isdpfxott Sgue Ab Ajib - Competent advice – before and after purchase - Provision of operating manuals, wiring diagrams & spare parts - Inspection according to DGUV V3 standards Technical data: - External dimensions (WxDxH): 360x470x1950 mm - Electric connection: 230V, 50Hz, 0.55kW - Serial number: 2892/22-60623 - Year of manufacture: 2022 - Capacity: 5 pairs of shoes Condition: Used, inspected, and fully functional SHIPPING: - Delivery or self-collection by arrangement - Worldwide shipping on request - Shipping to islands or mountain stations only by prior arrangement Do you have any questions, would you like advice, or would you like to view something onsite? You can reach us by phone during our opening hours: Monday–Friday 09:00 – 13:00 and 14:00 – 17:00. Sales are subject exclusively to our general terms and conditions (GTC).

Leto izdelave: 2022, stanje: dober (rabljeno), Funkcionalnost: popolnoma funkcionalen, This is a drying and disinfection system for boots and shoes from the manufacturer PHT, model HYGIfeet M5. The Hygifeet drying and disinfection system is an innovative solution for all locker and changing rooms. After use, the system stores boots and shoes, disinfecting and drying them at the same time. Disinfection is reliably carried out using ozone, completely eliminating the need for chemicals. Simultaneous drying is achieved by means of warm air, which ensures a short drying time. The ozone-warm air mixture is only released at the vent heads when boots are attached. Additionally, the vent heads are ergonomically shaped for optimal air circulation. Warm, dry boots enhance your employees' comfort and, thanks to disinfection, help prevent illnesses. The unit has been inspected in our in-house specialist workshop and is fully operational. The stated price is net plus 19% VAT. OUR USED EQUIPMENT SERVICE FOR YOU - 6 months warranty on all electrical components - High-quality branded equipment at fair prices - Professional overhaul / inspection & expert cleaning - Tested & fully functional – or your money back - Shipping or collection available to suit your needs - Expert advice – before and after your purchase - Provision of operating manuals, wiring diagrams & spare parts - Inspection in accordance with DGUV V3 Technical data: - External dimensions (W x D x H): 360 x 470 x 1950 mm - Electrical connection: 230 V, 50 Hz, 0.55 kW - Serial number: 2893/22-60623 - Year of manufacture: 2022 - Capacity: 5 pairs of shoes Iisdpjtt Sf Esfx Ab Aeb Condition: Used, inspected and fully functional SHIPPING: - Delivery or collection by arrangement - Worldwide shipping on request - Shipping to islands or mountain stations only by prior arrangement Do you have questions, need advice, or would like to view the equipment on site? You can reach us by phone during our business hours: Monday–Friday 09:00–13:00 and 14:00–17:00. Sale takes place exclusively according to our general terms and conditions (GTC).

Stanje: rabljeno, Ta električna naprava za zamrzovanje cevi Richebaecher se prodaja na naši industrijski dražbi / dražbi strojev zaradi čiščenja skladišča podjetja za gradbeno tehniko, ki poteka na spletu. Iisdpfx Abey Hrf Se Aeb To in številne druge pozicije najdete na naši platformi.

Stanje: zelo dobro (rabljeno), Leto izdelave: 1984, Funkcionalnost: popolnoma funkcionalen, premer struženja nad prečnim suportom: 630 mm, izvrtina vretena: 320 mm, premer struženja: 1.200 mm, premer struženja nad ležiščem sani: 930 mm, stružna dolžina: 3.000 mm, Lathe in very good technical condition, has seen very little use and was not utilized for machining pipes. Poręba TPL 90/3m lathe (also listed in market nomenclature as a variant of the TPK 90 series) is a textbook example of an Oil Country Lathe / Hollow Spindle Lathe. This model meets all the specific criteria for machines intended for the Oil & Gas sector: • Huge spindle bore (Big Bore): Machines in this version have a spindle bore diameter of 320 mm (approx. 12.5 inches), which allows for easy passage of thick-walled drill and casing pipes. • Dual chuck system: The headstock construction allows for the installation of two independent lathe chucks (front and rear, typically with a diameter of 28 inches), which clamp and stabilize the pipe at both ends of the spindle. • Optimal working range: The 3m designation defines the turning length between centers (3000 mm), which, combined with the swing over bed of 930 mm (hence the 90 in the model name), enables machining of massive pipeline elements. • Extreme rigidity: FUM POREBA products are renowned for their monolithic, very wide, and heavy cast iron beds, which effectively dampen the significant vibrations generated during thread cutting, especially with tapered threads. In international used machinery catalogs, this specific Poręba model is categorized directly under Oil Field Lathes. TECHNICAL DATA: Geometric parameters and machining ranges • Swing over bed: 930 mm / 36.6" • Swing over cross slide: 630 mm / 24.8" • Swing in gap: 1200 mm / 47.2" • Maximum turning length between centers: 3000 mm / 120" • Bed width: 585 mm / 23.0" Headstock • Spindle bore diameter (Hollow Spindle): 320 mm / 12.6" (classified in US nomenclature as 12.5" version) • Spindle speed range: 5 – 250 rpm or modified versions up to 710 rpm • Number of spindle speed steps: 18 Feed and threading system • Longitudinal feed range: 0.1 – 12.8 mm/rev / 0.004 – 0.504 in/rev • Cross feed range: 0.05 – 6.4 mm/rev / 0.002 – 0.252 in/rev • Types of threads cut: Metric, Inch (Whitworth), Module, Diametral Pitch (DP) Tailstock • Tailstock quill diameter: 130 mm / 5.1" • Tailstock quill stroke: 300 mm / 11.8" Iijdpsy Sf Azjfx Ab Asb • Quill taper: Morse No. 6 (MT6) Drive and overall dimensions • Main motor power: 22 kW / 29.5 HP • Total machine length: approx. 5500 mm / 216.5" • Total machine width: approx. 1750 mm / 68.9" • Total machine height: approx. 1500 mm / 59.0" • Total machine weight: approx. 8000 kg / 17,630 lbs

Stanje: novo, Funkcionalnost: popolnoma funkcionalen, Leto izdelave: 2025, Faser Lasermaschine für Rohre & Profile YLT 8025 - LAGERMASCHINE - SOFORT VERFÜGBAR Laserleistung: 4kW für Rohre und Profile Iiedpfeywub Rsx Ab Asb 8200mm Länge × 15-250mm Durchmesser rund 8200mm Länge × 15mm-200mm Quadtrat automatische Ladung 3000-8200 automatische Entladung 0-6000mm automatische Bündelbeladung für geschlossene Profile Ausstattung: 3 automatische Backenfutter zum Spannen und Zentrieren der Rohre Scheißnahterkennung Auto Fokus Schneidkopf Cypcut YNC5000 Steuerung mit Touchscreen MAX Resonator mit 4kW inkl. deutscher Garantie THX Führungen CE Sicherheit durch TÜV Süd Donaldson Absaugung wird inklusive: 2 Jahre Garantie CAD CAM Software Inbetriebnahme Lieferung innerhalb Dtl Schulung angeboten Wir betreuen YAWEI Maschinen für den europäischen Markt seit mehr als 20 Jahren. Wir sind Ihr Servicepartner für alle Fragen.

Stanje: rabljeno, Funkcionalnost: omejena funkcionalnost, 12 pasaž i valjčni mlin buhler-miag Celotna čistilnica Delovanje 1t/h pšenice Iijdpfx Abjyyqwmj Aob

Stanje: rabljeno, 1 kos kovinske krožne žage PEDRAZZOLI na paleti Barva: kot prikazano na slikah, skladno s fotografijami in ogledom Stanje: rabljeno Iodpfx Absy D I U Do Asib Skladišče blaga: skladiščna hala Način plačila: predplačilo z bančnim nakazilom Dostava: samo osebni prevzem na lokaciji Ditzingen-Heimerdingen

Stanje: rabljeno, Leto izdelave: 2021, obratovalne ure: 120 h, Funkcionalnost: popolnoma funkcionalen, Prodam utorni stroj Victaulic RG 3210 za oblikovanje koncev cevi D60,3 – 323,9. Stroj je bil uporabljen približno 1,5 leta v okviru projekta izdelave cevovodnih sklopov. Pribor: spodnje/zgornje utorno orodje 88,9 – 168,3 za nerjaveče jeklo, stojalo za podporo cevi. Zaradi zaključka projekta te opreme ne potrebujemo več. Prvotna cena: 184 440 CZK. Isdpfx Abey Hpate Asib

Leto izdelave: 1999, stanje: dober (rabljeno), Funkcionalnost: omejena funkcionalnost, !!! Important!!! The systems have now been dismantled. The system components can be inspected on site. For sale here are 2 fully functional SLC (Surface Like Chrome) vacuum coating systems / metallization units manufactured by PVT GmbH. A 3rd non-functional system is no longer available for sale. Complete documentation for the systems is available in paper form and will be handed over upon purchase. In order to operate the systems, a compressed air supply, power supply, and water cooling system are required and must be provided by the buyer. All other PVT processes are, of course, possible as well. Iisdpfx Aey N Eiveb Asb The system was primarily used for processing wheel rims. Treatment of other workpieces made of aluminum, steel, or plastic is also possible, such as bathroom/kitchen fittings, motorcycle and automotive add-on parts, door and window handles, etc. What are the advantages of the SLC process compared to conventional chrome plating: - SLC coating is a high-gloss finish optically comparable to electroplated chrome - Significantly more resistant to scratches and chipping - The process is more environmentally friendly and provides outstanding corrosion resistance - Costs are considerably lower Technical data: Chamber internal dimensions approx. 1600 mm diameter, approx. 900 mm height Type: PVT 1600 SLC Manufacturer: PVT GmbH Year of manufacture: 1998/1999 Documentation: available Control: Allen Bradley PLC (automatic coating process including hardware)

Stanje: zelo dobro (rabljeno), Leto izdelave: 2010, A very good inserting system suitable for C4, C5, and DIN long envelopes. This inserting system consists of: - 6798 Autoloader Iiedsh H Iuajpfx Ab Ajb - 6684 Single sheet feeder with display - 6995 Transfer unit - 6927 2D code camera - 6767 Transfer unit - 6786 Collation station - 6822 Folding machine with 6826 stop function - 6628 Multi-channel system - 6628 Multi-channel system - 6628 Multi-channel system - 6628 Multi-channel system - 6689 Insert feeder - 9006 Envelope feeder - 9006 Envelope section - 9006 Envelope closer - 6807d Envelope turner - 6960 Divert bin incl. stop function - 6959d Conveyor belt - 6963 Conveyor belt If you have any further questions, we are available via email or mobile.

Stanje: rabljeno, Funkcionalnost: popolnoma funkcionalen, Kolb RB5D Stencil Cleaning System Isdpfx Asqn U Hgob Ajib Operating hours: 1,781 h Stencil frame size: max. 750 x 585 mm Power: 1.7 kW, Connection: 230V Cleaning chamber capacity: 75 l Dimensions: 185 cm x 100 cm Weight: approx. 240 kg Shipping is possible by arrangement The machine is fully operational and ready for use. Please refer to the photos for the cosmetic condition and further details. The emergency stop key is no longer available. Options included: Operator platform made of VA aluminium Options included: Wash cycle counter and operating hours display #7891

Stanje: zelo dobro (rabljeno), Funkcionalnost: popolnoma funkcionalen, Leto izdelave: 2000, Kaiser razkladalna in sortirna linija tipa AS VAL 2 3-nadstropna sortirna tehnika z vakuumskim prijemom Ijdpfsy Iuulex Ab Aoib s paketnim skladiščenjem 2 sesalni škatli 2200 x 1700 Nosilnost 800 kg pri 60 % delovnega vakuuma Nosilnost na sesalno ploščo: 40 kg pri 60 % delovnega vakuuma

Stanje: kot nova (razstavni stroj), Funkcionalnost: popolnoma funkcionalen, skupna masa: 700 kg, skupna dolžina: 900 mm, skupna širina: 2.100 mm, skupna višina: 2.200 mm, vhodna napetost: 400 V, vhodna frekvenca: 50 Hz, priključek za stisnjen zrak: 5 letvica, električna varovalka: 20 A, Der Ringtester ist für die automatische Rissprüfung an ringförmigen Bauteilen wie Lagerringen und Zahnrädern mit dem eddyvisor C konzipiert. Zusätzlich können Kunden Schleifbrand an Innen- und Außenringen von Wälzlagern prüfen. Hierfür übernimmt ein Roboter das Handling und führt den Sensor entlang der Konturen des Prüfteils. Ijdpeyx E D Ejfx Ab Ajib Die Anlage prüft mit bis zu zwei Sonden. Alle relevanten Scanparameter sowie die Kommunikation zur Ansteuerung des eddyvisor C sind im Roboter-Scanprogramm integriert. Herzstück des Systems ist der eddyvisor C Wirbelstromprüfgerät mit zwei Kanälen zur zuverlässigen Riss- und Schleifbranddetektion. Die Prozessautomatisierung erfolgt durch einen integrierten Stäubli TX2-60 Roboter. Das gesamte System wird über einen Schaltschrank mit integriertem Steuer- und Bedienpanel gesteuert und bedient. Eine vertikale Spindel mit Spannfutter fixiert jedes Prüfling während der Inspektion sicher. Ausgeschleuste n.i.O.-Teile (NOK - not okay) werden automatisch auf zwei spezielle NOK-Ablagebahnen sortiert. Ein separater Lagerplatz für Referenz- und Masterteile unterstützt die Kalibrierung und laufende Qualitätssicherung während der Prüfung. Das System ist mit dem Optical Reflection Sensor von ibg (iORS) für präzise, berührungslose Inspektion von Ringen ausgestattet.

Leto izdelave: 2013, stanje: rabljeno, Funkcionalnost: popolnoma funkcionalen, številka stroja/vozila: 7.50.1081, Schneider & Koch AOI TS-LV6 / LaserVision Twin LV6 Avtomatiziran optični nadzorni sistem (rabljen 2D/3D-AOI za SMT tiskana vezja, popolnoma delujoč, letnik cca 2014–2016, za natančen pregled komponent, spajkalnih spojev in paste) Preizkusna tehnika Schneider & Koch Model: TS-LV6 Iisdpfx Aeyid Dueb Aob AOI naprava Funkcionalna

Stanje: dober (rabljeno), Funkcionalnost: popolnoma funkcionalen, 3 vložki za Multifix, velikost C, Iisdpfx Abjy Hf Awo Aeb

Stanje: dober (rabljeno), Leto izdelave: 1996, vrsta upravljanja: CNC krmiljenje, Premer cevi: 4-28 mm Debelina stene: / mm Minimalni polmer upogibanja: 1,5 x D - 2,0 x D mm Krmiljenje: Siemens LOGO Dovodna zmogljivost: 4,5 l/min Maksimalni upogibni kot +/-190° Nazivni tlak: 250 bar Obratovalni tlak: 3095 bar Iodjy Ixmxopfx Ab Ajib Dovodna zmogljivost: 4,5 l/min Skupna potrebna moč: 1,5 kW Pogon: hidravlični valj in valjčna veriga