{"id":2376,"date":"2026-06-30T08:59:01","date_gmt":"2026-06-30T08:59:01","guid":{"rendered":"https:\/\/hydrauliccylindersprice.com\/product\/hydraulic-press-clamping-cylinder\/"},"modified":"2026-06-30T08:59:03","modified_gmt":"2026-06-30T08:59:03","slug":"hydraulic-press-clamping-cylinder","status":"publish","type":"product","link":"https:\/\/hydrauliccylindersprice.com\/hi\/product\/hydraulic-press-clamping-cylinder\/","title":{"rendered":"Hydraulic Press Clamping Cylinder"},"content":{"rendered":"

<\/p>\n

<\/p>\n

\n
\n Hydraulic Press \u00b7 Clamping Cylinder<\/span><\/p>\n

Maximum Force.
Minimum Stroke.
Never Let Go.<\/h2>\n

Every other press cylinder acts and returns. The clamping cylinder acts and holds<\/em> \u2014 maintaining full grip pressure on a 1,200 \u00b0C steel billet for the entire forging sequence, through every press stroke, every manipulator rotation, every lateral shift. If the grip fails, the billet falls. There is no second chance.<\/p>\n

\n
\n
9,621 KN<\/div>\n
Max Thrust<\/div>\n<\/div>\n
\n
125\u2013700mm<\/span><\/div>\n
Bore Range<\/div>\n<\/div>\n
\n
\u22641,200mm<\/span><\/div>\n
Stroke<\/div>\n<\/div>\n
\n
Hold<\/div>\n
Continuous Pressure<\/div>\n<\/div><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

Grip \u2014 Not Move<\/h2>\n

The master cylinder presses down and returns. The return cylinder lifts up and retracts. The lateral shift cylinder slides sideways and slides back. Every other cylinder in the press system performs a motion \u2014 extend, do work, retract. The clamping cylinder is fundamentally different: it closes the jaws, then stays at pressure. Its job is not motion. Its job is continuous grip<\/strong>.<\/p>\n

The manipulator clamp head grips the billet between two jaws. The clamping cylinder drives these jaws together, squeezing the billet with enough force that the billet cannot slip \u2014 not during the press stroke (which sends shock waves through the billet), not during manipulator rotation (which applies torque), and not during lateral shifting (which applies lateral acceleration). The cylinder must hold this grip for the entire forging sequence \u2014 which can last 5\u201330 minutes per billet, encompassing dozens of press strokes. Korea Ever-Power engineers clamping cylinders for this continuous-duty requirement as part of the industrial engineering hydraulic cylinder<\/a> programme.<\/p>\n

\"Hydraulic
\n<\/section>\n

<\/p>\n

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Technical Specifications<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n
Parameter<\/th>\nValue<\/th>\n<\/tr>\n<\/thead>\n
Product<\/td>\nHydraulic Press Clamping Cylinder<\/td>\n<\/tr>\n
Function<\/td>\nGrip the steel ingot or billet in the manipulator clamp head<\/td>\n<\/tr>\n
Bore Diameter<\/td>\n125 mm \u2013 700 mm<\/td>\n<\/tr>\n
Rod Diameter<\/td>\n80 mm \u2013 520 mm<\/td>\n<\/tr>\n
Stroke<\/td>\n\u2264 1,200 mm<\/td>\n<\/tr>\n
Maximum Thrust<\/td>\n9,621 KN (bore 700 mm \/ pressure 25 MPa)<\/td>\n<\/tr>\n
Working Pressure<\/td>\nUp to 25 MPa<\/td>\n<\/tr>\n
Certification<\/td>\nISO 9001 \u00b7 100% hydrostatic tested<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n<\/section>\n

<\/p>\n

\n
\n

Engineering Insight \u2014 The Physics of Not Dropping a 10-Tonne Billet<\/h2>\n

The clamping force is not arbitrary \u2014 it is calculated from the billet weight, the friction between the jaw faces and the billet surface, and a safety factor that accounts for the dynamic forces during forging (shock, vibration, inertia from manipulator movement).<\/p>\n

\n

Required grip force:<\/strong><\/p>\n

Fclamp<\/sub> = (W \u00d7 S) \u00f7 (\u00b5 \u00d7 n)<\/p>\n

W = billet weight (N) \u00b7 S = safety factor (typically 3\u20135) \u00b7 \u00b5 = friction coefficient (0.15\u20130.3 for steel-on-steel at temperature) \u00b7 n = number of gripping faces (typically 2)<\/p>\n

\n
\n
10-tonne billet, \u00b5=0.2, S=4<\/div>\n
F = (98,000 \u00d7 4) \u00f7 (0.2 \u00d7 2) = 980 KN<\/div>\n<\/div>\n
\n
30-tonne billet, \u00b5=0.15, S=5<\/div>\n
F = (294,000 \u00d7 5) \u00f7 (0.15 \u00d7 2) = 4,900 KN<\/div>\n<\/div><\/div>\n<\/p><\/div>\n

The safety factor of 3\u20135 accounts for the press shock force (transmitted through the billet into the jaws), the inertial force during rapid manipulator rotation, and the possibility of reduced friction from oxide scale on the billet surface. Korea Ever-Power sizes the clamping cylinder bore to deliver the calculated grip force at the operating pressure \u2014 with the full safety margin. Contact the hydraulic cylinder engineering team<\/a> for clamping force calculations.<\/p>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

Continuous Pressure Hold \u2014 A Different Duty Cycle<\/h2>\n
\n \"Clamping<\/p>\n

Most hydraulic cylinders cycle: extend \u2192 work \u2192 retract \u2192 repeat. The clamping cylinder extends to close the jaws, then holds at full pressure for 5\u201330 minutes while the forging sequence proceeds. During this hold period, the cylinder must maintain pressure without any drop \u2014 because any pressure loss relaxes the jaw grip on the billet.<\/p>\n

This continuous hold creates different engineering demands than cyclic operation. The seals must resist static friction (stiction) \u2014 the tendency of elastomer seals to bond to the bore surface under sustained pressure. When the jaws finally open after a long hold, the seals must break free cleanly without stick-slip. Korea Ever-Power uses low-stiction seal compounds (PTFE-bronze composite piston seals) for clamping cylinders to ensure smooth jaw opening after prolonged pressure holds.<\/p>\n

The hydraulic circuit includes a pressure-maintaining valve (accumulator or check valve) that keeps the cylinder pressurised even if the pump is serving other cylinders on the manipulator. This guarantees uninterrupted grip regardless of what else the hydraulic system is doing \u2014 the tilt cylinder, the traverse cylinder, and the rotation cylinder can all be active without affecting the clamping pressure.<\/p>\n<\/p><\/div>\n

<\/div>\n<\/section>\n

<\/p>\n

\n \"Heavy
\n<\/section>\n

<\/p>\n

\n

125 mm to 700 mm Bore \u2014 Why the Range Is So Wide<\/h2>\n

No other auxiliary press cylinder spans such a wide bore range. The reason is that clamping forces vary enormously depending on what is being gripped \u2014 from a 500 kg billet on a small ring-rolling manipulator to a 50-tonne ingot on a heavy free-forging manipulator. The bore diameter scales directly with the required clamping force.<\/p>\n

\n
\n Small bore (125\u2013250 mm)<\/strong><\/p>\n

Ring rolling and pipe forging manipulators. Billets 0.5\u20135 tonnes. Clamping forces 300\u20131,200 KN. Fast jaw opening for rapid billet changeover during high-volume ring production. Compact cylinder fits within the manipulator arm envelope.<\/p>\n<\/p><\/div>\n

\n Medium bore (250\u2013450 mm)<\/strong><\/p>\n

General-purpose forging manipulators. Billets 5\u201320 tonnes. Clamping forces 1,500\u20134,000 KN. The most common size range \u2014 covers the majority of open-die forging operations producing shafts, blocks, and stepped forgings.<\/p>\n<\/p><\/div>\n

\n Large bore (450\u2013700 mm)<\/strong><\/p>\n

Heavy free-forging manipulators on 40\u201380 MN presses. Billets 20\u201350+ tonnes. Clamping forces 5,000\u20139,621 KN. These are among the largest auxiliary cylinders manufactured \u2014 the 700 mm bore approaches the size of a small master cylinder. The grip force must hold multi-tonne ingots during the shock of an 80 MN press stroke.<\/p>\n<\/p><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

When the Grip Fails \u2014 Consequences and Prevention<\/h2>\n
\n \"Clamping<\/p>\n

A clamping cylinder failure during forging has immediate, severe consequences. The hot billet \u2014 weighing tonnes, at temperatures that instantly ignite anything it touches \u2014 drops from the manipulator onto the press bolster, the floor, or worse. The billet is unpredictable: it may bounce, roll, or shatter if it has internal cracks from the forging process.<\/p>\n

Prevention relies on three layers. First, the clamping force calculation includes a safety factor of 3\u20135\u00d7, so the actual grip far exceeds the minimum needed. Second, the hydraulic circuit includes a pilot-operated check valve on the clamp port that locks the cylinder at pressure even if the supply line loses pressure. Third, pressure sensors monitor the clamp circuit continuously \u2014 any pressure drop triggers an immediate press-stop interlock and an alarm.<\/p>\n

Korea Ever-Power designs every clamping cylinder with the check-valve mounting face integrated into the cylinder head \u2014 not as a remote installation. This eliminates the hose segment between the cylinder and the check valve, removing the most common failure point (hose burst between cylinder and valve = instant pressure loss = instant grip loss).<\/p>\n<\/p><\/div>\n

<\/div>\n<\/section>\n

<\/p>\n

\n

Manufacturing<\/h2>\n

\"Korea<\/p>\n

The clamping cylinder’s short stroke (\u22641,200 mm) means the barrel is compact, but the large bore (up to 700 mm) demands heavy-duty machining: CNC boring and honing at 700 mm diameter requires large-swing lathes and custom honing tooling. The piston \u2014 up to 700 mm diameter \u2014 is a substantial forged component that must be machined, sealed, and assembled with tight concentricity to the bore. Korea Ever-Power’s large-bore machining capability covers the full 125\u2013700 mm range. Seals for the continuous-hold duty cycle are selected from low-stiction compounds (PTFE-bronze composite) to prevent jaw sticking after prolonged pressure holds. Every cylinder is hydrostatic tested at 1.5\u00d7 working pressure with a hold test \u2014 verifying zero pressure drop over a defined period that simulates the continuous-grip duty cycle.<\/p>\n<\/section>\n

<\/p>\n

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OEM & ODM<\/h2>\n
\n
\n
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What You Provide<\/h3>\n<\/div>\n
\n

Maximum billet weight (tonnes), billet cross-section range (diameter or width \u00d7 height), jaw face material and surface condition (serrated \/ flat \/ V-groove), jaw opening distance (determines stroke), manipulator type (rail, column, or floor-mounted), dynamic load conditions (press tonnage, manipulator rotation speed), and the clamp head mechanical drawing.<\/p>\n<\/div><\/div>\n

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What the Factory Delivers<\/h3>\n<\/div>\n
\n

Engineering drawing with bore, rod, stroke, clamping force verified against your safety factor, seal specification for continuous-hold duty, check-valve mounting detail, and pressure-sensor provisions. Hydrostatic test + hold test certificate. Seal kits for scheduled overhaul. Browse all industrial manipulator and press cylinders<\/a>.<\/p>\n<\/div><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

FAQ<\/h2>\n
\n
\n

Why is the stroke so short compared to other press cylinders?<\/h3>\n

The stroke only needs to open the jaws wide enough to accept the billet, then close them. For a billet cross-section of 200\u2013800 mm, the jaw opening needs to be 300\u20131,000 mm. The cylinder stroke matches this jaw opening \u2014 typically 400\u20131,200 mm. Unlike the mobile workbench (7,500 mm travel) or even the return cylinder (4,500 mm), the clamping cylinder does not travel far \u2014 it just squeezes hard.<\/p>\n<\/p><\/div>\n

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Can the clamping force be adjusted for different billet sizes?<\/h3>\n

Yes \u2014 the clamp pressure is set by a proportional pressure valve in the hydraulic circuit. Lighter billets receive lower clamping pressure (preventing jaw marks on softer alloys); heavier billets receive full pressure. The cylinder itself operates across the full pressure range \u2014 the valve controls how much pressure is applied. This proportional control is essential for forge shops that process a range of billet sizes and alloy grades.<\/p>\n<\/p><\/div>\n

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Is the clamping cylinder the same as a workholding cylinder on a CNC machine?<\/h3>\n

Conceptually similar (both grip a workpiece), but the forging press clamping cylinder operates at a completely different scale \u2014 10\u2013100\u00d7 the force, 5\u201310\u00d7 the bore diameter, and under extreme thermal and shock conditions that CNC workholding never encounters. The seal materials, construction, and safety features are specific to the forging environment. The same heavy-duty cylinder engineering<\/a> applies to clamping applications in forklift clamp attachments<\/a> and dump body latch cylinders<\/a>.<\/p>\n<\/p><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

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Related Categories<\/h2>\n
\n <\/p>\n
\n
\"Telescopic\"<\/div>\n
\n
Telescopic Hydraulic Cylinders \u2192<\/div>\n
Dump truck, trailer, hoist.<\/div>\n<\/div>\n<\/div>\n

<\/a>
\n <\/p>\n

\n
\"Forklift\"<\/div>\n
\n
Forklift Hydraulic Cylinders \u2192<\/div>\n
Lift, tilt, steer \u2014 OEM.<\/div>\n<\/div>\n<\/div>\n

<\/a>
\n <\/p>\n

\n
\"AWV\"<\/div>\n
\n
Aerial Work Vehicle Cylinders \u2192<\/div>\n
Scissor, boom, platforms.<\/div>\n<\/div>\n<\/div>\n

<\/a>\n <\/div>\n<\/section>\n

<\/main><\/p>","protected":false},"excerpt":{"rendered":"

Hydraulic press clamping cylinder \u2014 the grip-force actuator that tightens the manipulator clamp head around a hot steel ingot or billet and holds it securely throughout the entire forging sequence. Every other press cylinder moves something \u2014 pushes, lifts, shifts, tilts. This one squeezes and holds. The clamping cylinder delivers the highest thrust of any auxiliary press cylinder \u2014 up to 9,621 KN (nearly 1,000 tonnes-force) \u2014 across the shortest stroke: \u22641,200 mm. It needs just enough travel to open and close the jaws, then it locks at full pressure and does not let go until the forging is complete. Bore 125\u2013700 mm, rod 80\u2013520 mm, 25 MPa. Korea Ever-Power. ISO 9001. OEM & ODM.<\/div>","protected":false},"featured_media":2377,"comment_status":"closed","ping_status":"open","template":"","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":""},"product_brand":[],"product_cat":[852],"product_tag":[],"class_list":["post-2376","product","type-product","status-publish","has-post-thumbnail","product_cat-industrial-engineering-hydraulic-cylinders","pa_editor-cxm","first","instock","product-type-simple"],"_links":{"self":[{"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/product\/2376","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/comments?post=2376"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/media\/2377"}],"wp:attachment":[{"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/media?parent=2376"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/product_brand?post=2376"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/product_cat?post=2376"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/hi\/wp-json\/wp\/v2\/product_tag?post=2376"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}