[{"data":1,"prerenderedAt":1116},["ShallowReactive",2],{"catalog:meta":3,"guides:page:\u002Finjection-molding-machine-parts\u002Fhydraulics:*":258,"guides:topics:hydraulics::path,title,short,description,item":709,"diagram:id:hydraulic-system":835,"catalog:parts:hydraulics:HY-AU-02,HY-CV-06,HY-MO-01,HY-PW-02,HY-PW-05,HY-PW-06,HY-PW-07":1028},{"categories":4,"machines":132,"zones":212,"totals":255},[5,35,59,122],{"id":6,"name":7,"slug":8,"description":9,"partCount":10,"subcategories":11},"EC","Electrical Components","electrical","Electrical systems and components for injection molding machines including heaters, thermocouples, servo motors, and controllers.",11,[12,17,22,27,31],{"id":13,"name":14,"slug":15,"partCount":16},"EC-CBC","Circuit Boards & Controllers","circuit-boards",4,{"id":18,"name":19,"slug":20,"partCount":21},"EC-CE","Connectors & Cables","connectors-cables",2,{"id":23,"name":24,"slug":25,"partCount":26},"EC-GEP","Servo Motors & Drives","servo-motors",1,{"id":28,"name":29,"slug":30,"partCount":21},"EC-HT","Heaters","heaters",{"id":32,"name":33,"slug":34,"partCount":21},"EC-SF","Safety Components","safety",{"id":36,"name":37,"slug":38,"description":39,"partCount":40,"subcategories":41},"HY","Hydraulic Components","hydraulic","Complete range of hydraulic system components including pumps, valves, motors, and pressure controls for injection molding machines.",14,[42,46,51,55],{"id":43,"name":44,"slug":45,"partCount":26},"HY-AU","Accumulators","accumulators",{"id":47,"name":48,"slug":49,"partCount":50},"HY-CV","Control Valves","control-valves",6,{"id":52,"name":53,"slug":54,"partCount":26},"HY-MO","Monitors & Gauges","monitors-gauges",{"id":56,"name":57,"slug":58,"partCount":50},"HY-PW","Pumps & Motors","pumps-motors",{"id":60,"name":61,"slug":62,"description":63,"partCount":64,"subcategories":65},"MC","Mechanical Components","mechanical","Mechanical parts and assemblies including barrels, screws, tie bars, bushings, platens, and clamping components.",42,[66,71,75,80,85,89,93,97,101,105,109,114,118],{"id":67,"name":68,"slug":69,"partCount":70},"MC-BC","Barrels & Cylinders","barrels-cylinders",5,{"id":72,"name":73,"slug":74,"partCount":16},"MC-SB","Screw Barrels & Seals","screws",{"id":76,"name":77,"slug":78,"partCount":79},"MC-TC","Tie Bars & Columns","tie-bars",7,{"id":81,"name":82,"slug":83,"partCount":84},"MC-GZ","Bushings & Guides","bushings-guides",8,{"id":86,"name":87,"slug":88,"partCount":26},"MC-PP","Platens","platens",{"id":90,"name":91,"slug":92,"partCount":70},"MC-TL","Toggle & Links","toggle-links",{"id":94,"name":95,"slug":96,"partCount":21},"MC-CC","Clamping Components","clamping",{"id":98,"name":99,"slug":100,"partCount":21},"MC-GMP","Tools & Accessories","tools-accessories",{"id":102,"name":103,"slug":104,"partCount":21},"MC-ES","End Caps & Plates","end-caps",{"id":106,"name":107,"slug":108,"partCount":26},"MC-SR","Seals & Rings","seals-rings",{"id":110,"name":111,"slug":112,"partCount":113},"MC-JM","Joints & Mounts","joints-mounts",3,{"id":115,"name":116,"slug":117,"partCount":26},"MC-SG","Safety Guards","safety-guards",{"id":119,"name":120,"slug":121,"partCount":26},"MC-CR","Clamping Mechanism","clamping-mechanism",{"id":123,"name":124,"slug":125,"description":126,"partCount":113,"subcategories":127},"O","Other Components","other","Additional components including filters, cooling systems, lubrication parts, and other auxiliary equipment.",[128],{"id":129,"name":130,"slug":131,"partCount":113},"O-TC","Filters & Cooling","filters-cooling",[133,143,161,172,180,188,194,200,205],{"id":134,"name":135,"slug":134,"series":136,"partCount":142},"haitian","Haitian International",[137,138,139,140,141],"Mars Series (MA)","Jupiter Series (JU)","Zhafir Venus Series (VE)","Zhafir Zeres Series (ZE)","Zhafir Jeres Series (JE)",68,{"id":144,"name":145,"slug":144,"series":146,"partCount":160},"yizumi","Yizumi",[147,148,149,150,151,152,153,154,155,156,157,158,159],"A6 Series","A5-EU Series","A5-N Series","SKIII Series","DP Series","D1 Series","FF Series","FF-M Series","P Series","CG-P Series","VM Series","SPET Series","LSR Series",12,{"id":162,"name":163,"slug":162,"series":164,"partCount":171},"chen-hsong","Chen Hsong",[165,166,167,168,169,170],"JETMASTER MK Series","JETMASTER SVP Series","SUPERMASTER Series","EASYMASTER Series","SPARK Series","JETMASTER C2 Series",10,{"id":173,"name":174,"slug":173,"series":175,"partCount":179},"tederic","Tederic",[176,177,178],"NEO Series","D Series (Two-Platen)","DE Series (All-Electric)",0,{"id":181,"name":182,"slug":181,"series":183,"partCount":179},"borch","Borch",[184,185,186,187],"BU Series (Two-Platen)","BS-III Series (Servo)","BE Series (All-Electric)","BM Series (Multi-color)",{"id":189,"name":190,"slug":189,"series":191,"partCount":179},"log-machine","LOG Machine",[192,193],"LOG-SE Series","LOG-EE Series (All-Electric)",{"id":195,"name":196,"slug":195,"series":197,"partCount":179},"donghua","Donghua",[198,199],"DH Series (Servo)","DH-TP Series (Two-Platen)",{"id":201,"name":202,"slug":201,"series":203,"partCount":179},"sunbun","Sunbun",[204],"Sunbun Servo Series",{"id":206,"name":207,"slug":206,"series":208,"partCount":179},"lijin","L.K. Machinery (Lijin)",[209,210,211],"POTENZA Series","FORZA Series (Two-Platen)","ELETTRICA Series (All-Electric)",[213,217,221,225,228,231,235,238,242,248,251],{"id":214,"number":26,"name":215,"role":216,"partCount":21},"clamp-cylinder","Clamping cylinder","The hydraulic cylinder behind the rear platen. It drives the crosshead that straightens the toggle links, which opens and closes the mold and builds the clamping force.",{"id":218,"number":21,"name":219,"role":220,"partCount":50},"toggle","Toggle mechanism","Links, pins and bushings between the rear and moving platens. They multiply the force of the clamping cylinder and lock the mold shut while plastic is injected.",{"id":222,"number":113,"name":223,"role":224,"partCount":113},"ejector","Ejector","A small cylinder behind the moving platen that pushes the ejector rods and plate forward to release the finished part from the mold.",{"id":78,"number":16,"name":226,"role":227,"partCount":40},"Tie bars & bushings","Four steel columns that join the platens, guide the moving platen and carry the clamping force. Tie bar nuts lock them in place; bushings guide the moving platen along them.",{"id":88,"number":70,"name":229,"role":230,"partCount":21},"Platens & mold plates","The fixed and moving platens carry the two halves of the mold; the rear platen anchors the toggle. Locating rings and clamping plates center and hold the mold.",{"id":232,"number":50,"name":233,"role":234,"partCount":50},"barrel-screw","Barrel, screw & nozzle","The screw turns inside the heated barrel to melt and mix the plastic, then moves forward to inject it through the nozzle into the mold. The screw tip and check ring stop melt from flowing back.",{"id":30,"number":79,"name":236,"role":237,"partCount":113},"Heater bands & sensors","Heater bands around the barrel and nozzle melt the plastic. Thermocouples measure each heating zone so the controller can hold the set temperature.",{"id":239,"number":84,"name":240,"role":241,"partCount":79},"injection-unit","Injection unit","Injection cylinders push the screw forward, the hydraulic (plasticizing) motor turns it, and the carriage moves the unit against the mold on its guide rails.",{"id":243,"number":244,"name":245,"role":246,"partCount":247},"hydraulics",9,"Hydraulic unit","The pump, motor, valves, accumulator, filters and oil cooler in the machine base. They supply and control the oil pressure for every movement of the machine.",16,{"id":8,"number":171,"name":249,"role":250,"partCount":244},"Electrical cabinet","The controller, I\u002FO and drive boards, servo drives, contactors and safety switches that run and protect the machine.",{"id":252,"number":10,"name":253,"role":254,"partCount":21},"feet","Machine feet","Leveling bolts and anti-vibration pads under the machine base that keep the machine level and stop vibration spreading to the floor.",{"parts":256,"subcategories":257},70,23,{"id":259,"title":260,"body":261,"description":681,"diagram":682,"extension":683,"faq":684,"item":700,"lastModified":701,"meta":702,"navigation":703,"order":700,"parts":700,"path":704,"seo":705,"seoTitle":706,"short":700,"stem":707,"__hash__":708},"guides\u002Finjection-molding-machine-parts\u002Fhydraulics.md","Hydraulic system of an injection molding machine",{"type":262,"value":263,"toc":660},"minimark",[264,268,273,276,279,314,323,327,332,340,344,351,355,362,366,373,377,404,408,421,425,453,457,464,468,486,490,497,501,519,523,535,539,584,592,596,613,633,637],[265,266,267],"p",{},"The hydraulic system is the power source of a hydraulic injection molding machine. An electric motor drives a pump, the pump sends oil under pressure to a block of valves, and the valves direct it to the cylinders and the hydraulic motor that move the mold, the injection unit, the screw and the ejector. The numbered drawing above shows the main parts, from the oil tank to a cylinder; this guide explains what each one does, the faults that show up most often, and what to send when you need a replacement.",[269,270,272],"h2",{"id":271},"how-the-hydraulic-system-works","How the hydraulic system works",[265,274,275],{},"The oil travels in a loop. The pump draws it from the tank through a suction filter and delivers it to the valve manifold. The valves open a path to one actuator at a time (sometimes two), and the oil pushed out of the other side of the actuator returns through the oil cooler to the tank.",[265,277,278],{},"During a cycle, the valves switch the oil in roughly this order:",[280,281,282,290,296,302,308],"ol",{},[283,284,285,289],"li",{},[286,287,288],"strong",{},"Mold close and clamp."," The clamp cylinder closes the mold quickly, slows down for mold protection, then builds the clamping force, directly or through the toggle.",[283,291,292,295],{},[286,293,294],{},"Carriage forward."," The carriage cylinders push the injection unit forward until the nozzle touches the mold.",[283,297,298,301],{},[286,299,300],{},"Injection and hold."," The injection cylinder drives the screw forward at the set speed, then holds pressure while the part cools.",[283,303,304,307],{},[286,305,306],{},"Screw recovery."," While the part cools, the plasticizing motor turns the screw to melt the next shot, against the set back pressure.",[283,309,310,313],{},[286,311,312],{},"Mold open and ejection."," The clamp opens and the ejector cylinder pushes the part out.",[265,315,316,317,322],{},"Each step needs its own pressure and flow. On a machine with a constant-speed motor and a fixed pump, a proportional valve sets them and the surplus oil returns to the tank. With a variable piston pump, the pump control reduces the pump's displacement instead. On a servo pump machine, the servo motor changes the pump speed. The ",[318,319,321],"a",{"href":320},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fhydraulic-circuit\u002F","hydraulic circuit page"," shows how these circuits are drawn and how to read the diagram in your machine manual.",[269,324,326],{"id":325},"the-parts-of-the-hydraulic-system","The parts of the hydraulic system",[328,329,331],"h3",{"id":330},"oil-tank","Oil tank",[265,333,334,335,339],{},"The tank, usually built into the machine base, holds the oil. Returning oil settles there and sheds heat and air before the pump draws it again. A sight glass shows the level, and a breather lets air in and out as the level changes. See the ",[318,336,338],{"href":337},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Foil-tank\u002F","oil tank page",".",[328,341,343],{"id":342},"suction-filter","Suction filter",[265,345,346,347,339],{},"A strainer on the pump's suction line inside the tank keeps dirt and metal particles out of the pump; many also carry a magnet for iron particles. A blocked suction filter starves the pump and makes it noisy. Return-line filters, where fitted, clean the oil coming back. See the ",[318,348,350],{"href":349},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Foil-filter\u002F","oil filter page",[328,352,354],{"id":353},"electric-motor-or-servo-motor","Electric motor or servo motor",[265,356,357,358,339],{},"On conventional machines a three-phase induction motor drives the pump at constant speed. Energy-saving machines use a servo motor and drive that turn the pump only as fast as each step of the cycle needs. See ",[318,359,361],{"href":360},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fservo-pump\u002F","servo pump systems",[328,363,365],{"id":364},"coupling-and-bell-housing","Coupling and bell housing",[265,367,368,369,339],{},"The bell housing bolts the pump to the motor flange and keeps the two shafts in line; a flexible jaw coupling inside carries the torque and absorbs vibration. A worn coupling insert often shows up as a knock at start-up. See the ",[318,370,372],{"href":371},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpump-coupling\u002F","pump coupling page",[328,374,376],{"id":375},"hydraulic-pump","Hydraulic pump",[265,378,379,380,384,385,389,390,394,395,399,400,339],{},"The pump turns the motor's rotation into oil flow. Injection molding machines use ",[318,381,383],{"href":382},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fvane-pump\u002F","vane pumps",", ",[318,386,388],{"href":387},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpiston-pump\u002F","axial piston pumps"," and ",[318,391,393],{"href":392},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fgear-pump\u002F","gear pumps",". Constant-speed machines mostly use vane or piston pumps, and servo-hydraulic machines often use internal gear pumps. The ",[318,396,398],{"href":397},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fhydraulic-pump\u002F","hydraulic pump types"," page compares them and explains how to identify yours. With the motor, coupling and tank, the pump forms the ",[318,401,403],{"href":402},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpower-unit\u002F","hydraulic power unit",[328,405,407],{"id":406},"pressure-gauge-and-pressure-transducer","Pressure gauge and pressure transducer",[265,409,410,411,415,416,420],{},"A ",[318,412,414],{"href":413},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpressure-gauge\u002F","pressure gauge"," shows the system pressure at a glance, so the operator can check the settings and notice a pressure loss early. A ",[318,417,419],{"href":418},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpressure-transducer\u002F","pressure transducer"," measures pressure electrically and sends the signal to the controller or the servo drive for display, alarms and pressure control.",[328,422,424],{"id":423},"valve-manifold","Valve manifold",[265,426,427,428,432,433,437,438,442,443,447,448,452],{},"The ",[318,429,431],{"href":430},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fvalve-manifold\u002F","valve manifold"," is a steel block drilled with oil passages, with the valves bolted onto it or screwed into it. ",[318,434,436],{"href":435},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fdirectional-valve\u002F","Solenoid directional valves"," start, stop and reverse each movement, ",[318,439,441],{"href":440},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fproportional-valve\u002F","proportional valves"," set its pressure and speed, ",[318,444,446],{"href":445},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fcartridge-valve\u002F","cartridge valves"," switch the large flows of the clamp and injection circuits, and ",[318,449,451],{"href":450},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fhydraulic-check-valve\u002F","check valves"," let oil flow one way only.",[328,454,456],{"id":455},"relief-valve","Relief valve",[265,458,427,459,463],{},[318,460,462],{"href":461},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Frelief-valve\u002F","relief valve"," limits the highest pressure in the system. When the pressure goes above its setting, it opens and sends oil to the tank, protecting the pump, hoses and cylinders.",[328,465,467],{"id":466},"hydraulic-cylinders-and-motor","Hydraulic cylinders and motor",[265,469,470,471,475,476,480,481,485],{},"Cylinders turn oil pressure into straight-line force for clamping, injecting, ejecting and moving the injection unit: see the ",[318,472,474],{"href":473},"\u002Finjection-molding-machine-parts\u002Fclamp-cylinder\u002F","clamp cylinder guide"," and the ",[318,477,479],{"href":478},"\u002Finjection-molding-machine-parts\u002Finjection-unit\u002Finjection-cylinder\u002F","injection cylinder",". The screw is turned by a low-speed, high-torque ",[318,482,484],{"href":483},"\u002Finjection-molding-machine-parts\u002Finjection-unit\u002Fplasticizing-motor\u002F","plasticizing motor",". Worn piston seals let oil pass inside a cylinder, so the movement gets slower and weaker; worn rod seals show as oil leaking at the rod.",[328,487,489],{"id":488},"accumulator","Accumulator",[265,491,492,493,496],{},"An ",[318,494,488],{"href":495},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Faccumulator\u002F"," stores oil under nitrogen pressure and releases it in a burst, giving more flow than the pump alone for high-speed injection. It also absorbs pressure peaks. Machines without a high-speed injection option often have none.",[328,498,500],{"id":499},"oil-cooler-and-cooling-water","Oil cooler and cooling water",[265,502,503,504,508,509,513,514,518],{},"A water-cooled ",[318,505,507],{"href":506},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Foil-cooler\u002F","oil cooler"," on the return line removes the heat the system produces and keeps the ",[318,510,512],{"href":511},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Foil-temperature\u002F","oil temperature"," steady. Its water comes through the machine's ",[318,515,517],{"href":516},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fcooling-water-manifold\u002F","cooling water manifold",", so a closed or blocked water circuit soon shows as hot oil.",[328,520,522],{"id":521},"hydraulic-oil","Hydraulic oil",[265,524,427,525,529,530,534],{},[318,526,528],{"href":527},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fhydraulic-oil\u002F","hydraulic oil"," transmits the power, lubricates the pumps and valves and carries heat away. Its grade, cleanliness and temperature decide how long the pumps, valves and seals last. Our article on ",[318,531,533],{"href":532},"\u002Fblog\u002Fhydraulic-oil-problems-injection-molding\u002F","hydraulic oil problems"," covers dirt, overheating, air and water in the oil.",[269,536,538],{"id":537},"common-hydraulic-problems-and-their-symptoms","Common hydraulic problems and their symptoms",[540,541,542,548,554,560,566,572,578],"ul",{},[283,543,544,547],{},[286,545,546],{},"Pressure loss or weak movements:"," clamp force or injection pressure below the setting, slow movements, longer cycles. Typical causes are a worn pump, a relief or proportional valve that does not hold, internal leakage in a valve or cylinder, a blocked suction filter or a low oil level.",[283,549,550,553],{},[286,551,552],{},"Oil running hot:"," a relief valve passing oil, internal leakage in worn parts, too little cooling water or a fouled cooler.",[283,555,556,559],{},[286,557,558],{},"Noisy pump:"," a whine or rattle from cavitation (blocked suction filter, low level, cold and thick oil, a closed suction valve), air drawn in through a suction leak, a worn pump or a worn coupling.",[283,561,562,565],{},[286,563,564],{},"Jerky or unstable movements:"," air in the oil, a sticking valve spool, a faulty proportional valve or amplifier, a low accumulator pre-charge, or a faulty pressure transducer on a servo machine.",[283,567,568,571],{},[286,569,570],{},"A movement does not happen:"," no output from the controller, a burnt solenoid coil, a stuck spool or cartridge valve.",[283,573,574,577],{},[286,575,576],{},"A cylinder drifts or does not hold:"," a leaking check valve or cartridge valve seat, or worn piston seals.",[283,579,580,583],{},[286,581,582],{},"External leaks:"," hoses, fittings, the O-rings under valves and the pump shaft seal.",[265,585,586,587,591],{},"Work from the supply outward: check the oil level, temperature and filter first, then the pressure at the pump outlet, then the valves and cylinders of the faulty movement. Our guide to ",[318,588,590],{"href":589},"\u002Fblog\u002Ftroubleshooting-hydraulic-pressure-loss\u002F","troubleshooting hydraulic pressure loss"," gives a step-by-step test.",[269,593,595],{"id":594},"what-to-send-for-a-replacement-quote","What to send for a replacement quote",[280,597,598,601,604,607,610],{},[283,599,600],{},"The machine brand, model and serial number, and whether it has a fixed pump, a variable pump or a servo pump.",[283,602,603],{},"The model code from the part's nameplate. On pumps and valves it gives the series, size, control and options.",[283,605,606],{},"Photos of the part from several sides, its nameplate and its connections: ports, flange, shaft and electrical plug.",[283,608,609],{},"For valves, the coil voltage (AC or DC) and the connector type. For pumps, the direction of rotation, the shaft and the flange. For accumulators, the volume and the oil port.",[283,611,612],{},"The page of the hydraulic circuit diagram that shows the part, if you have the manual.",[265,614,615,616,384,620,389,624,627,628,632],{},"Browse our ",[318,617,619],{"href":618},"\u002Fcategories\u002Fhydraulic\u002Fpumps-motors\u002F","hydraulic pumps and motors",[318,621,623],{"href":622},"\u002Fcategories\u002Fhydraulic\u002Fcontrol-valves\u002F","control valves",[318,625,45],{"href":626},"\u002Fcategories\u002Fhydraulic\u002Faccumulators\u002F",", then ",[318,629,631],{"href":630},"\u002Frequest-quote\u002F","request a quote"," with these details.",[269,634,636],{"id":635},"maintenance-of-the-hydraulic-system","Maintenance of the hydraulic system",[540,638,639,642,645,648,651,654,657],{},[283,640,641],{},"Check the oil level and temperature every day. A level that keeps dropping means a leak.",[283,643,644],{},"Change the filter elements at the interval in the machine manual, and every time a pump or valve fails, because its debris stays in the circuit.",[283,646,647],{},"Change or test the oil at the manual's interval, use the grade it specifies, and do not mix brands.",[283,649,650],{},"Keep the cooling water clean and flowing through the oil cooler.",[283,652,653],{},"Check the accumulator pre-charge at the interval in the manual, always with the oil side drained.",[283,655,656],{},"Keep the circuit clean whenever it is opened: cap ports and hoses, clean mounting faces, and fill a new pump with oil before starting it.",[283,658,659],{},"Record the pump outlet pressure, oil temperature and movement times while the machine is healthy, so you have figures to compare with later.",{"title":661,"searchDepth":21,"depth":21,"links":662},"",[663,664,678,679,680],{"id":271,"depth":21,"text":272},{"id":325,"depth":21,"text":326,"children":665},[666,667,668,669,670,671,672,673,674,675,676,677],{"id":330,"depth":113,"text":331},{"id":342,"depth":113,"text":343},{"id":353,"depth":113,"text":354},{"id":364,"depth":113,"text":365},{"id":375,"depth":113,"text":376},{"id":406,"depth":113,"text":407},{"id":423,"depth":113,"text":424},{"id":455,"depth":113,"text":456},{"id":466,"depth":113,"text":467},{"id":488,"depth":113,"text":489},{"id":499,"depth":113,"text":500},{"id":521,"depth":113,"text":522},{"id":537,"depth":21,"text":538},{"id":594,"depth":21,"text":595},{"id":635,"depth":21,"text":636},"How the hydraulic system of an injection molding (moulding) machine works: pumps, power unit, valves, accumulator, oil care, common faults and quote details.","hydraulic-system","md",[685,688,691,694,697],{"question":686,"answer":687},"What does the hydraulic system do on an injection molding machine?","It powers the machine's movements. A motor-driven pump delivers oil to a valve manifold, and the valves send it to the cylinders and the hydraulic motor that close and clamp the mold, move the injection unit, inject, turn the screw and eject the part.",{"question":689,"answer":690},"Why is my injection molding machine losing hydraulic pressure?","The usual causes are a worn pump, a relief or proportional valve that does not hold its setting, internal leakage in a valve or a cylinder seal, a blocked suction filter or a low oil level. A gauge reading at the pump outlet tells you whether the fault is in the supply or further down the circuit.",{"question":692,"answer":693},"What is the difference between a fixed pump and a servo pump machine?","On a fixed pump machine the motor runs at constant speed and a proportional valve sets pressure and flow, sending the surplus oil back to the tank. On a servo pump machine a servo motor changes the pump speed so it delivers only the flow and pressure each movement needs, which uses less energy and heats the oil less.",{"question":695,"answer":696},"Why does the hydraulic oil get too hot?","Heat comes from oil losing pressure without doing work: oil passing a relief valve, internal leakage in worn pumps and valves, or a fixed pump sending surplus flow to the tank. A cooler with too little water flow or fouled tubes makes it worse.",{"question":698,"answer":699},"What information is needed to quote a hydraulic part?","The machine brand, model and serial number, the model code from the part's nameplate, and photos of the part and its connections. For valves add the coil voltage; for pumps add the shaft, flange and direction of rotation.",null,"2026-11-01",{},true,"\u002Finjection-molding-machine-parts\u002Fhydraulics",{"title":260,"description":681},"Injection Molding Machine Hydraulic System: Parts and Faults","injection-molding-machine-parts\u002Fhydraulics","D2N9CnAF-pksbDVxZTsMWj1V0ZMHp85D5jRraLaYmX0",[710,715,721,726,731,736,742,748,754,760,766,772,778,783,788,793,797,803,809,814,819,824,830],{"path":711,"title":712,"short":713,"description":714,"item":700},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fhydraulic-circuit","Hydraulic circuit of an injection molding machine","Hydraulic circuit","How the hydraulic circuit of an injection molding machine is built and how to read its diagram: symbols, ports, pressure and flow control, and each circuit.",{"path":716,"title":717,"short":718,"description":719,"item":720},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fhydraulic-pump","Hydraulic pump of an injection molding machine","Hydraulic pump types","The hydraulic pump types used on injection molding machines (vane, piston, gear), fixed and variable displacement, signs of failure and how to identify a pump.","pump",{"path":722,"title":723,"short":724,"description":725,"item":720},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fvane-pump","Vane pump of an injection molding machine","Vane pump","How the vane pump of an injection molding machine works, the PV2R, SQP, Vickers V and VQ and 50T series, model codes, signs of wear and what to send for a quote.",{"path":727,"title":728,"short":729,"description":730,"item":720},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpiston-pump","Piston pump of an injection molding machine","Piston pump","How the variable axial piston pump of an injection molding machine works: pressure control, case drain, Yuken A and ARL1 codes, signs of wear and replacement.",{"path":732,"title":733,"short":734,"description":735,"item":720},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fgear-pump","Gear pump of an injection molding machine","Gear pump","How external and internal gear pumps work on injection molding machines, where they are used (including servo pump systems), signs of wear and quote details.",{"path":737,"title":738,"short":739,"description":740,"item":741},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fservo-pump","Servo pump system of an injection molding machine","Servo pump system","How a servo pump for an injection moulding machine works: servo motor, drive, fixed pump and pressure feedback, its common faults and what to send for a quote.","motor",{"path":743,"title":744,"short":745,"description":746,"item":747},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpump-coupling","Pump coupling and bell housing of an injection molding machine","Pump coupling","What the pump coupling and bell housing do between the motor and pump of an injection molding machine, signs of wear, replacement steps and what to measure.","coupling",{"path":749,"title":750,"short":751,"description":752,"item":753},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpower-unit","Hydraulic power unit of an injection molding machine","Hydraulic power unit","What the hydraulic power unit of an injection molding machine includes (motor, coupling, pump, tank), common faults, and replacing a complete pump-motor unit.","unit",{"path":755,"title":756,"short":757,"description":758,"item":759},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fdirectional-valve","Solenoid directional valve of an injection molding machine","Directional valve","How the solenoid directional valve of an injection molding machine starts, stops and reverses movements: Cetop sizes, spool types, coil faults and replacement.","directional",{"path":761,"title":762,"short":763,"description":764,"item":765},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fproportional-valve","Proportional valve of an injection molding machine","Proportional valve","How the proportional pressure and flow valve sets speeds and pressures on an injection molding machine, its amplifier, common faults, testing and calibration.","proportional",{"path":767,"title":768,"short":769,"description":770,"item":771},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fcartridge-valve","Cartridge valve of an injection molding machine","Cartridge valve","How slip-in cartridge (logic) valves switch the large flows of clamp and injection circuits in an injection molding machine manifold, faults and servicing.","cartridge",{"path":773,"title":774,"short":775,"description":776,"item":777},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fhydraulic-check-valve","Hydraulic check valve of an injection molding machine","Hydraulic check valve","How the hydraulic check valve in the oil circuit of an injection molding machine works (not the screw check ring): types, where it is used, faults and replacement.","check",{"path":779,"title":780,"short":456,"description":781,"item":782},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Frelief-valve","Relief valve of an injection molding machine","How the relief valve (safety valve) limits pressure in an injection molding machine: direct and pilot-operated types, signs of a faulty valve and safe setting.","relief",{"path":784,"title":785,"short":424,"description":786,"item":787},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fvalve-manifold","Valve manifold of an injection molding machine","What the hydraulic valve manifold (valve block) of an injection molding machine does, the valves mounted on it, leaks and other faults, and how to service it.","block",{"path":789,"title":790,"short":489,"description":791,"item":792},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Faccumulator","Accumulator of an injection molding machine","How the bladder accumulator of an injection molding machine stores oil for high-speed injection: its parts, nitrogen pre-charge checks, safety and signs of failure.","shell",{"path":794,"title":795,"short":522,"description":796,"item":700},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fhydraulic-oil","Hydraulic oil for injection molding machines","Which hydraulic oil an injection molding machine uses, what the ISO VG grade means, how oil degrades, how to check its condition and how to change it correctly.",{"path":798,"title":799,"short":800,"description":801,"item":802},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Foil-temperature","Oil temperature of an injection molding machine","Oil temperature","Why injection molding machine oil temperature matters, the typical working range, what makes the oil run too hot or too cold, and how to find the cause.","cooler",{"path":804,"title":805,"short":806,"description":807,"item":808},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Foil-filter","Hydraulic oil filter of an injection molding machine","Oil filter","How the hydraulic oil filters of an injection molding machine work, suction, return and pressure filters, the signs of a clogged filter and how to replace it.","filter",{"path":810,"title":811,"short":812,"description":813,"item":802},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Foil-cooler","Oil cooler (heat exchanger) of an injection molding machine","Oil cooler","How the water-cooled oil cooler of an injection molding machine works, shell-and-tube and plate types, signs of a fouled or leaking cooler, cleaning and replacement.",{"path":815,"title":816,"short":331,"description":817,"item":818},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Foil-tank","Hydraulic oil tank of an injection molding machine","What the hydraulic oil tank of an injection molding machine does, its baffle, breather, level gauge and drain plug, common problems and how to clean it.","tank",{"path":820,"title":821,"short":822,"description":823,"item":700},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fcooling-water-manifold","Cooling water manifold of an injection molding machine","Cooling water manifold","What the cooling water manifold of an injection molding machine feeds (oil cooler, feed throat, mold circuits), its valves and flow meters, and common faults.",{"path":825,"title":826,"short":827,"description":828,"item":829},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpressure-gauge","Hydraulic pressure gauge of an injection molding machine","Pressure gauge","How the glycerin-filled hydraulic pressure gauge of an injection molding machine works, how to choose and check one, signs of failure and how to quote it.","case",{"path":831,"title":832,"short":833,"description":834,"item":700},"\u002Finjection-molding-machine-parts\u002Fhydraulics\u002Fpressure-transducer","Pressure transducer of an injection molding machine","Pressure transducer","What the hydraulic pressure transducer of an injection molding machine does, how it feeds pressure control, typical faults, testing and replacement.",{"diagram":836},{"title":837,"description":838,"base":839,"items":847},"Parts of the hydraulic system","Line drawing of an injection molding machine hydraulic system: oil tank, filter, motor, pump, valves, gauge, accumulator, cooler and a cylinder, numbered.",{"line":840},[841,842,843,844,845,846],"M200 186L200 140L270 140","M362 96L362 68L450 68","M378 96L378 44L565 44L565 50","M476 232L390 232L390 164","M330 164L330 244L540 244L540 262","M520 276L456 276",[848,860,873,892,905,920,940,962,977,994,1010],{"id":818,"name":331,"role":849,"subcategory":129,"marker":850,"shapes":854},"Holds the hydraulic oil. Returning oil settles here and sheds heat and air before the pump draws it again.",[851,852,851,853],120,336,304,{"solid":855,"hidden":858},[856,857],"M39 250h414a3 3 0 0 1 3 3v48a3 3 0 0 1 -3 3h-414a3 3 0 0 1 -3 -3v-48a3 3 0 0 1 3 -3z","M420 242h18v8h-18z",[859],"M44 262L448 262",{"id":808,"name":343,"role":861,"subcategory":129,"marker":862,"shapes":865},"Strainer on the pump’s suction line inside the tank. It keeps dirt and metal particles out of the pump.",[863,852,863,864],202,296,{"solid":866,"line":868},[867],"M194 268h16a2 2 0 0 1 2 2v24a2 2 0 0 1 -2 2h-16a2 2 0 0 1 -2 -2v-24a2 2 0 0 1 2 -2z",[869,870,871,872],"M202 230L202 268","M196 275L208 275","M196 282L208 282","M196 289L208 289",{"id":741,"name":874,"role":875,"subcategory":23,"marker":876,"shapes":880},"Electric motor","Drives the pump. Newer machines use a servo motor that only runs as fast as the cycle needs, which saves energy.",[877,878,877,879],98,24,174,{"solid":881,"line":885},[882,883,884],"M58 186h80a6 6 0 0 1 6 6v44a6 6 0 0 1 -6 6h-80a6 6 0 0 1 -6 -6v-44a6 6 0 0 1 6 -6z","M80 174h30v12h-30z","M58 242h80v8h-80z",[886,887,888,889,890,891],"M64 192L64 236","M76 192L76 236","M88 192L88 236","M100 192L100 236","M112 192L112 236","M124 192L124 236",{"id":747,"name":365,"role":893,"parts":894,"marker":896,"shapes":900},"The bell housing bolts the pump to the motor and keeps the shafts aligned. The flexible coupling inside carries the torque.",[895],"HY-PW-05",[897,878,898,899],150,162,196,{"solid":901,"hidden":903},[902],"M144 192L180 200L180 228L144 236Z",[904],"M154 206h16v16h-16z",{"id":720,"name":376,"role":906,"parts":907,"marker":911,"shapes":914},"Turns the motor’s rotation into oil flow. Fixed-speed machines mostly use vane or piston pumps; servo-hydraulic machines often use internal gear pumps.",[908,909,910],"HY-PW-06","HY-PW-07","HY-PW-02",[863,878,912,913],215,198,{"solid":915,"line":918},[916,917],"M183 198h38a3 3 0 0 1 3 3v26a3 3 0 0 1 -3 3h-38a3 3 0 0 1 -3 -3v-26a3 3 0 0 1 3 -3z","M193 186h14v12h-14z",[919],"M187 199L187 229",{"id":921,"name":827,"role":922,"parts":923,"marker":925,"shapes":929},"gauge","Shows the system pressure, so the operator can check the settings and spot a pressure loss early.",[924],"HY-MO-01",[926,878,927,928],254,238,90,{"solid":930,"line":932},[931],"M220 106a16 16 0 1 0 32 0a16 16 0 1 0 -32 0z",[933,934,935,936,937,938,939],"M236 140L236 122","M236 106L245 96","M227.51471862576142 114.48528137423857L225.3933982822018 116.60660171779821","M224.91344560986457 101.40779881161892L222.1418070123307 100.25974851452365","M236 94L236 91","M247.08655439013543 101.40779881161892L249.8581929876693 100.25974851452365","M244.48528137423858 114.48528137423857L246.6066017177982 116.60660171779821",{"id":941,"name":424,"role":942,"subcategory":47,"marker":943,"shapes":946},"valves","The valve block that sends oil to each movement. Solenoid valves on top and cartridge valves inside switch clamping, injection, ejection and nozzle movements.",[944,878,944,945],318,96,{"solid":947,"line":958},[948,949,950,951,952,953,954,955,956,957],"M272 120h128a2 2 0 0 1 2 2v40a2 2 0 0 1 -2 2h-128a2 2 0 0 1 -2 -2v-40a2 2 0 0 1 2 -2z","M276 100h12v16h-12z","M290 96h32a2 2 0 0 1 2 2v20a2 2 0 0 1 -2 2h-32a2 2 0 0 1 -2 -2v-20a2 2 0 0 1 2 -2z","M324 100h12v16h-12z","M340 100h12v16h-12z","M354 96h32a2 2 0 0 1 2 2v20a2 2 0 0 1 -2 2h-32a2 2 0 0 1 -2 -2v-20a2 2 0 0 1 2 -2z","M388 100h12v16h-12z","M291 142a7 7 0 1 0 14 0a7 7 0 1 0 -14 0z","M329 142a7 7 0 1 0 14 0a7 7 0 1 0 -14 0z","M367 142a7 7 0 1 0 14 0a7 7 0 1 0 -14 0z",[959,960,961],"M295.5 142a2.5 2.5 0 1 0 5 0a2.5 2.5 0 1 0 -5 0z","M333.5 142a2.5 2.5 0 1 0 5 0a2.5 2.5 0 1 0 -5 0z","M371.5 142a2.5 2.5 0 1 0 5 0a2.5 2.5 0 1 0 -5 0z",{"id":782,"name":456,"role":963,"parts":964,"marker":966,"shapes":970},"Opens when the pressure goes above its setting and sends the oil back to the tank, protecting the pump, hoses and cylinders.",[965],"HY-CV-06",[967,878,968,969],410,427,135,{"solid":971,"line":975},[972,973,974],"M402 130h18v24h-18z","M420 135h14v14h-14z","M442 137h6v10h-6z",[976],"M434 142L442 142",{"id":978,"name":979,"role":980,"subcategory":94,"marker":981,"shapes":985},"cylinder","Hydraulic cylinder","Turns oil pressure into straight-line force: for clamping the mold, injecting, ejecting and moving the injection unit.",[982,878,983,984],530,510,56,{"solid":986,"hidden":991},[987,988,989,990],"M450 50h10v36h-10z","M462 56h96a2 2 0 0 1 2 2v20a2 2 0 0 1 -2 2h-96a2 2 0 0 1 -2 -2v-20a2 2 0 0 1 2 -2z","M560 50h10v36h-10z","M570 62h44v12h-44z",[992,993],"M500 58h10v20h-10z","M510 68L560 68",{"id":488,"name":489,"role":995,"parts":996,"marker":998,"shapes":1002},"Stores oil under nitrogen pressure and releases it in a burst for fast injection, more flow than the pump alone delivers.",[997],"HY-AU-02",[999,1000,1001,1000],616,160,512,{"solid":1003,"hidden":1008},[1004,1005,1006,1007],"M496 104h0a16 16 0 0 1 16 16v80a16 16 0 0 1 -16 16h0a16 16 0 0 1 -16 -16v-80a16 16 0 0 1 16 -16z","M490 94h12v10h-12z","M490 216h12v10h-12z","M476 226h40v12h-40z",[1009],"M496 114h0a10 10 0 0 1 10 10v60a10 10 0 0 1 -10 10h0a10 10 0 0 1 -10 -10v-60a10 10 0 0 1 10 -10z",{"id":802,"name":812,"role":1011,"subcategory":129,"marker":1012,"shapes":1015},"Water-cooled heat exchanger on the return line. It keeps the oil from overheating, which would thin it and wear the seals and pumps.",[1013,852,1013,1014],562,290,{"solid":1016,"line":1020,"hidden":1025},[1017,1018,1019],"M534 262h56a14 14 0 0 1 14 14v0a14 14 0 0 1 -14 14h-56a14 14 0 0 1 -14 -14v0a14 14 0 0 1 14 -14z","M530 290h8v14h-8z","M586 290h8v14h-8z",[1021,1022,1023,1024],"M534 263L534 289","M590 263L590 289","M604 270L616 270","M604 282L616 282",[1026,1027],"M534 272L590 272","M534 280L590 280",[1029,1037,1044,1051,1056,1060,1066,1072,1077,1081,1086,1090,1095,1101,1106,1111],{"partNumber":997,"name":1030,"subcategory":43,"subcategoryName":44,"shortDescription":1031,"image":1032,"inStock":703,"zone":243,"compatibleMachines":1033},"Hydraulic Accumulator","Bladder-type hydraulic accumulator for injection molding machine high-speed injection circuits.","\u002Fpart-images\u002FHY\u002FHY-AU-02\u002FHY-AU-02.jpg",[1034,1035,1036],"Haitian MA Series","Haitian Jupiter Series","Chen Hsong JM Series",{"partNumber":1038,"name":1039,"subcategory":47,"subcategoryName":48,"shortDescription":1040,"image":1041,"inStock":703,"zone":243,"compatibleMachines":1042},"HY-CV-02","Directional Control Valve","Solenoid-operated directional control valve for injection molding machine hydraulic circuits.","\u002Fpart-images\u002FHY\u002FHY-CV-02\u002Feeaecc6c53657d38d48089a1344d4bce.jpg",[1034,1035,1043,1036],"Yizumi A5 Series",{"partNumber":1045,"name":1046,"subcategory":47,"subcategoryName":48,"shortDescription":1047,"image":1048,"inStock":703,"zone":243,"compatibleMachines":1049},"HY-CV-04","Proportional Pressure\u002FFlow Valve","Proportional solenoid valve for precise pressure and flow control in injection molding machines.","\u002Fpart-images\u002FHY\u002FHY-CV-04\u002F06e2c777-c0f3-4739-8046-c59de63bbd4e.png",[1034,1050,1043],"Haitian MA II Series",{"partNumber":1052,"name":1053,"subcategory":47,"subcategoryName":48,"shortDescription":1054,"inStock":703,"zone":243,"compatibleMachines":1055},"HY-CV-05","Check Valve","Hydraulic check valve for injection molding machine circuits.",[1034,1035],{"partNumber":965,"name":1057,"subcategory":47,"subcategoryName":48,"shortDescription":1058,"inStock":703,"zone":243,"compatibleMachines":1059},"Relief Valve \u002F Safety Valve","Hydraulic relief and safety valve for injection molding machine system pressure protection.",[1034,1035,1036],{"partNumber":1061,"name":1062,"subcategory":47,"subcategoryName":48,"shortDescription":1063,"image":1064,"inStock":703,"zone":243,"compatibleMachines":1065},"HY-CV-08","Cartridge Valve","Hydraulic cartridge valve for injection molding machine manifold blocks.","\u002Fpart-images\u002FHY\u002FHY-CV-08\u002F41953eeb-f34f-4462-bdad-956e39dcf40b.png",[1035,1050],{"partNumber":1067,"name":1068,"subcategory":47,"subcategoryName":48,"shortDescription":1069,"inStock":703,"zone":243,"compatibleMachines":1070},"HY-CV-15","Solenoid Operated Valve — High Flow","High-flow solenoid operated directional valve for large-tonnage injection molding machines.",[1035,1071],"Haitian MA II 1200T+",{"partNumber":924,"name":1073,"subcategory":52,"subcategoryName":1074,"shortDescription":1075,"inStock":703,"zone":243,"compatibleMachines":1076},"Hydraulic Pressure Gauge","Monitoring & Instruments","Glycerin-filled hydraulic pressure gauge for injection molding machine system monitoring.",[1034,1035,1043],{"partNumber":910,"name":1078,"subcategory":56,"subcategoryName":57,"shortDescription":1079,"inStock":703,"zone":243,"compatibleMachines":1080},"Gear Pump (Sumitomo QT32)","Sumitomo QT32 series internal gear pump for injection molding machine hydraulic systems.",[1034,1043],{"partNumber":1082,"name":1083,"subcategory":56,"subcategoryName":57,"shortDescription":1084,"inStock":703,"zone":243,"compatibleMachines":1085},"HY-PW-03","Hydraulic Power Unit \u002F Oil Pump Assembly","Complete hydraulic pump motor assembly for injection molding machine power unit.",[1034,1035],{"partNumber":895,"name":1087,"subcategory":56,"subcategoryName":57,"shortDescription":1088,"inStock":703,"zone":243,"compatibleMachines":1089},"Pump Coupling & Bell Housing","Pump coupling and bell housing adapter for injection molding machine hydraulic pump drives.",[1034,1035],{"partNumber":908,"name":1091,"subcategory":56,"subcategoryName":57,"shortDescription":1092,"image":1093,"inStock":703,"zone":243,"compatibleMachines":1094},"Hydraulic Vane Pump","High-performance hydraulic vane pump for injection molding machine hydraulic power units.","\u002Fpart-images\u002FHY\u002FHY-PW-06\u002FVickers vane pump\u002F20V,25V,35.jpg",[1034,1035,1036],{"partNumber":909,"name":1096,"subcategory":56,"subcategoryName":57,"shortDescription":1097,"image":1098,"inStock":703,"zone":243,"compatibleMachines":1099},"Hydraulic Piston Pump","Variable displacement hydraulic piston pump for high-pressure injection molding machine applications.","\u002Fpart-images\u002FHY\u002FHY-PW-07\u002FYUKEN Piston Pump\u002FWechatIMG807.jpg",[1034,1035,1100],"Chen Hsong SM Series",{"partNumber":1102,"name":1103,"subcategory":129,"subcategoryName":130,"shortDescription":1104,"inStock":703,"zone":243,"compatibleMachines":1105},"O-TC-02","Hydraulic Oil Filter","Self-sealing magnetic suction oil filter for injection molding machine hydraulic tanks.",[1034,1035,1043],{"partNumber":1107,"name":1108,"subcategory":129,"subcategoryName":130,"shortDescription":1109,"inStock":703,"zone":243,"compatibleMachines":1110},"O-TC-04","Oil Cooler \u002F Heat Exchanger","Hydraulic oil cooler (heat exchanger) for injection molding machine oil temperature control.",[1034,1035,1036],{"partNumber":1112,"name":1113,"subcategory":129,"subcategoryName":130,"shortDescription":1114,"inStock":703,"zone":243,"compatibleMachines":1115},"O-TC-05","Oil Tank \u002F Hydraulic Reservoir","Hydraulic oil reservoir tank for injection molding machine power unit.",[1034,1035],1793548975171]