Single piston pump of the EKO series - Putzmeister Solid Pumps

The EKO series2Single piston pump based on the thrust principleFile under: A 1.00, BP 1.03, A 4.00, BP 4.03Principle of function andpump constructionThe material to be conveyed is fed intothe pump via a material feeding hopper.1. A hydraulic drive cylinder moves theplunger forwards and backwards. Asthe piston is retracting, the feedchamber is filled.2. The plunger pushes the compressedmaterial out of the feed chamber intothe supply cylinder.3. The slide valve opens on entry of theplunger into the cylinder.4. The hydraulically driven plungerdelivers the material into the pipeline.5. The gate valve closes the pipeline,preventing any reverse flow material.In addition, this prevents „burn back“from the furnace.6. The plunger returns to its startingpositon, thus opening the feedchamber allowing the material toenter.Awkward shapes or oversize materialsmay additonally have to be pressed intothe material feed area using a compactor(Fig. 6).In the case of sticky materials, there is adanger of bridging. This problem is solvedby the compactor as well (Fig. 6).123453The gate valveA special gate valve designed for extremelyheavy loading prevents back-flow ofmaterial from the discharge pipe. Thisgate valve is directly attached to the outletflange of the EKO and is operated viathe pump’s control system. An automaticgreasing system guarantees reliableoperation, even with continuous use. Thespecially formed, robust valve blade ismade from highly wear resistant steel,which easily shears foreign bodies onclosing.For bulky dry material that cannot flowback (e.g. screenings), a lamellar nonreturnvalve is used (Fig. 4). This is asimply-added economical and reliablesystem.Plunger with cutting edgeThe EKO crown …… cuts and transportsin one operationFor the most demanding of requirements,the EKO crown is used.This pump is used where the materialcontains large foreign bodies. In othersystems, these often lead to blocking ofthe pump.The EKO crown has a transport pistonwith a hardened and toothed cutting edge(Fig. 5). Foreign bodies (metal, steel,glass, wood, etc.) that may come betweenthe piston and the inlet to the feed54chamber, are simply cut through. Thus amedium that may, for instance, containlong metal strips, can be transported intothe discharge pipe without problems.A double chromium-plated and hardenedplunger and various types of seales (e.g.Viton) are only two of the features thatsignificantly increase the life-time of theEKO crown, making it capable of withstandingthe most extreme demands.Other performance features of the EKOcrown illustrate its reliability:■ If a foreign body sticks between thepiston and the material feed chamber,or if the material jams in the pipeline,the EKO crown switches over auto-Dosing auger(WaDo = waste dosing)matically to half stroke speed. At thesame time, the piston drive powerdoubles. The foreign body is cut upwith double the force. Blockages arecleared automatically.■ If the foreign body should still bestuck, the piston automatically retractsa short distance and is thenpushed forward again. This processrepeats up to three times. This „loosening“procedure usually leads tocontinuation of the flow.■ If the foreign body cannot be removedin this way, a fault signal is automaticallygiven to alert the operatorand permit the pump to be drivenclear in manual operating mode.CompactorMaintenance valve6The hybrid feed systemEven with dry materials that are prone tobridging, long distances can be overcome.It is for just such cases that the“hybrid feed system“ is designed.(The „hybrid“ designation denoteshydraulic + pneumatic).It functions on the „pneumatic delivery“principle. Compressed air is injected intothe pipeline. This separates and fluidizesthe material. Depending on the quantityof air, the material which is initially in theform of plugs can, with increaing distance,become a steady airborne stream.In this way, extending feeding distancesare possible.The feed air mixes readily with the combustionair in the furnace.87ABCDEFFBDEDelivery linesECAThe principle of thehybrid feed systemCompressed airShut-off valveT-piece for air injectionPressure line for compression streamPlug of materialDelivery lineThe EKO is further complimented by awide range of delivery line options. TheZX coupling system, for instance, allowsa particularly flexible and economicalpipeline arrangement.109 11The hydraulic unitThe EKO is fitted with a hydraulic driveunit. This operates the delivery piston,the gate valve, and the bridge breakerand compactor.The hydraulic unit permits an optimaladjustment of the required „feed“ pressuresand quantities. The feed rate can beadjusted manually or automatically at theequipment, or from a remote monitoringpoint.For automatic operation, delivery rateinformation such as oil temperature, oilpressure and filter status, etc. are clearlydisplayed, and recorded if required.A sticky consistency can also result inoverfilling, with the consequence thatblockages can form. This can be avoidedby metered dosing of the material usinga dosing auger (Fig. 6).6The „EKO-Duo“EKO 1060 with lamellar non-return valveIP 2253-4 GBIP 2253-4 GB