{"id":2420,"date":"2026-06-30T08:59:20","date_gmt":"2026-06-30T08:59:20","guid":{"rendered":"https:\/\/hydrauliccylindersprice.com\/product\/mold-opening-and-closing-hydraulic-cylinder-for-vulcanizing-machine\/"},"modified":"2026-06-30T08:59:24","modified_gmt":"2026-06-30T08:59:24","slug":"mold-opening-and-closing-hydraulic-cylinder-for-vulcanizing-machine","status":"publish","type":"product","link":"https:\/\/hydrauliccylindersprice.com\/sk\/product\/mold-opening-and-closing-hydraulic-cylinder-for-vulcanizing-machine\/","title":{"rendered":"Mold Opening and Closing Hydraulic Cylinder for Vulcanizing Machine"},"content":{"rendered":"

<\/p>\n

<\/p>\n

\n
\n
\n Vulcanizing Machine<\/span>
\n Mold Opening & Closing Cylinder<\/span>\n <\/div>\n

4 Metres Up.
One Tire Out.
4 Metres Down.<\/h2>\n

The injection moulding mold opening cylinder (#26) needs 700 mm of stroke \u2014 enough to separate two flat platens for a thin plastic part. The vulcanizing mold opening cylinder needs 4,000 mm \u2014 because a tire is not a flat part. The upper mold dome must lift high enough to clear the cured tire, the centre mechanism, and the loading arm that swings in to grab the tire. Same name, same function, 6\u00d7 the stroke \u2014 because the product geometry demands it.<\/p>\n

\n
\n
\u22644,000mm<\/span><\/div>\n
Stroke (6\u00d7 Injection)<\/div>\n<\/div>\n
\n
50\u2013140mm<\/span><\/div>\n
Bore<\/div>\n<\/div>\n
\n
384 KN<\/div>\n
Max Thrust<\/div>\n<\/div>\n
\n
150\u2013180\u00b0C<\/div>\n
Mold Temperature<\/div>\n<\/div><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

Why the Vulcanizing Mold Needs 4,000 mm of Opening \u2014 Not 700 mm<\/h2>\n

An injection mould opens just enough to separate two flat halves and drop out a thin plastic part \u2014 300\u2013700 mm is sufficient. A vulcanizing mold is different: the lower half is a deep container holding the bottom sidewall and most of the tread shape; the upper half is a dome that forms the top sidewall and the upper tread. The cured tire sits inside this container, partially enclosed by the centre mechanism (the bladder mandrel that shapes the tire’s inner surface).<\/p>\n

To remove the tire, the upper dome must rise far enough for the loading arm to swing horizontally between the dome and the tire \u2014 gripping the tire from above and lifting it out of the container. The clearance must accommodate the dome height (300\u2013600 mm), the tire section height (150\u2013400 mm), the loading arm mechanism (400\u2013800 mm), and a safety margin for the operator’s sight line. These clearances sum to 2,000\u20134,000 mm depending on the tire size and press layout. Korea Ever-Power manufactures the mold opening\/closing cylinder as the motion actuator of the vulcanizing machine cylinder family<\/a>.<\/p>\n

\"Mold
\n<\/section>\n

<\/p>\n

\n

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>\nMold Opening and Closing Hydraulic Cylinder for Vulcanizing Machine<\/td>\n<\/tr>\n
Function<\/td>\nRaise upper mold dome \/ lower it for closure<\/td>\n<\/tr>\n
Bore Diameter<\/td>\n50 mm \u2013 140 mm<\/td>\n<\/tr>\n
Rod Diameter<\/td>\n28 mm \u2013 100 mm<\/td>\n<\/tr>\n
Stroke<\/td>\n\u2264 4,000 mm<\/td>\n<\/tr>\n
Maximum Thrust<\/td>\n384 KN (bore 140 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

Dome and Container \u2014 Why a Tire Mold Is Not Two Flat Halves<\/h2>\n
\n \"Vulcanizing<\/p>\n

An injection mold has two flat-backed halves that bolt to flat platens. A vulcanizing mold has a fundamentally different geometry because a tire is a toroidal (doughnut-shaped) object that wraps around a centre mechanism.<\/p>\n

Upper dome (top mold half):<\/strong> A curved dome shape that forms the top sidewall of the tire \u2014 including the sidewall lettering, DOT markings, and the upper bead seat. The dome is heated by steam channels and lifts vertically when the mold opening cylinder retracts.<\/p>\n

Lower container (bottom mold half):<\/strong> A deep container that holds the tread segments (on segmented molds) and forms the bottom sidewall. The container stays on the press bed \u2014 it does not move. The cured tire sits in this container after the dome lifts.<\/p>\n

Centre mechanism (bladder assembly):<\/strong> A vertical post in the centre of the mold that carries the rubber bladder. The bladder inflates inside the green tire during cure, pressing the rubber outward into the mold cavity. After cure, the bladder deflates and retracts. The centre mechanism protrudes upward from the container \u2014 the dome must lift high enough to clear this protrusion before the loading arm can access the tire.<\/p>\n<\/p><\/div>\n

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

<\/p>\n

\n
\n

The Opening Sequence \u2014 Five Steps, Three Cylinders<\/h2>\n

The mold opening is not a single motion \u2014 it is a coordinated sequence involving three different vulcanizing machine cylinders:<\/p>\n

\n
\n
\n
1<\/div>\n
<\/div>\n<\/div>\n
Pressurized cylinder (#29) depressurises<\/strong><\/p>\n

Clamping force released in 1\u20133 seconds. The bladder deflates simultaneously. The mold halves are now unloaded but still touching.<\/p>\n<\/div><\/div>\n

\n
\n
2<\/div>\n
<\/div>\n<\/div>\n
Mold opening cylinder (#30) breaks the dome free<\/strong><\/p>\n

The initial pull separates the dome from the tire’s upper sidewall \u2014 breaking the adhesion between the cured rubber and the hot mold surface. This break-free force is the highest load the opening cylinder sees.<\/p>\n<\/div><\/div>\n

\n
\n
3<\/div>\n
<\/div>\n<\/div>\n
Mold opening cylinder (#30) raises dome to full height<\/strong><\/p>\n

Fast upward traverse \u2014 the dome clears the centre mechanism, rises above the tire, and stops at the maximum opening height. Speed matters: every second of mold-open time is a second the mold cools, wasting energy on reheat.<\/p>\n<\/div><\/div>\n

\n
\n
4<\/div>\n
<\/div>\n<\/div>\n
Loading\/unloading cylinder (#33) removes the tire<\/strong><\/p>\n

The loading arm swings in horizontally, grips the tire, lifts it out of the container, and transfers it to the tipping mechanism (#28).<\/p>\n<\/div><\/div>\n

\n
\n
5<\/div>\n<\/div>\n
Closing \u2014 reverse sequence<\/strong><\/p>\n

The loading arm places a new green tire in the container. The mold opening\/closing cylinder lowers the dome. The pressurized cylinder engages clamping force. The next cure cycle begins. Contact the hydraulic cylinder engineering team<\/a> for complete vulcanizing press cycle specifications.<\/p>\n<\/div><\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

Hot Mold, Long Stroke \u2014 Three Engineering Challenges the Injection Cylinder Never Faces<\/h2>\n
\n
\n Thermal expansion changes the closed position<\/strong><\/p>\n

At 180 \u00b0C, the steel mold and press frame expand by 1\u20133 mm compared to room temperature. The cylinder’s “fully closed” position at operating temperature is not the same as at cold start-up. The control system must compensate \u2014 using the pressurized cylinder’s force (not the opening cylinder’s position) to confirm full mold closure. The opening cylinder must accommodate this thermal growth within its stroke range.<\/p>\n<\/p><\/div>\n

\n Rubber adhesion varies with cure recipe<\/strong><\/p>\n

The force needed to break the dome free from the cured tire’s sidewall depends on the rubber compound, the mold release agent application, and the cure temperature. Some high-performance rubber compounds adhere more aggressively to the mold surface \u2014 requiring the opening cylinder to deliver a higher break-free force than standard passenger car tire formulations. Korea Ever-Power sizes the bore to handle the worst-case adhesion force in the customer’s product range.<\/p>\n<\/p><\/div>\n

\n Vertical 4-metre rod exposed to heat<\/strong><\/p>\n

When the mold is closed, the cylinder rod is retracted inside the barrel \u2014 protected. When the mold opens fully, 4 metres of chrome rod is exposed to the hot air rising from the open mold (60\u2013120 \u00b0C). FKM seals and heavy chrome plating (50\u201380 \u00b5m) protect against the thermal environment, and the same long-stroke buckling and rod-droop considerations from the cement roll over cylinder (#22) apply here.<\/p>\n<\/p><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n \"Mold
\n<\/section>\n

<\/p>\n

\n

Manufacturing \u2014 Long Stroke, Hot Environment, Vertical Duty<\/h2>\n
\n \"Korea<\/p>\n

The mold opening\/closing cylinder combines two engineering challenges that appear separately in other products: the long stroke of the cement roll over cylinder (#22) and the hot environment of the pressurized vulcanizing cylinder (#29). Korea Ever-Power applies both skill sets to this cylinder.<\/p>\n

The rod is buckling-verified for the specific press frame geometry (typically vertical mounting \u2014 the rod hangs downward from the press crown, supporting the dome weight). The rod chrome plating is 50\u201380 \u00b5m for thermal and corrosion resistance. FKM seals accommodate the 60\u2013120 \u00b0C ambient temperature at the cylinder’s mounting position. The bore is honed to Ra 0.2\u20130.4 \u00b5m over the full 4-metre stroke length \u2014 requiring a long-stroke honing pass that maintains uniform surface finish from end to end.<\/p>\n

Every mold opening\/closing cylinder is hydrostatic tested at 1.5\u00d7 working pressure (37.5 MPa) and functionally tested for full 4-metre extend and retract with cushion verification at both the open and closed positions.<\/p>\n<\/p><\/div>\n

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

<\/p>\n

\n

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

Dome weight (tonnes), required opening height, mold-break adhesion force (from compound data or press builder experience), open\/close speed, mounting orientation (vertical or inclined), distance from cylinder to mold surface (thermal assessment), press frame drawing showing crown structure and cylinder mounting, and the loading arm clearance requirement.<\/p>\n<\/div><\/div>\n

\n
\n

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

Engineering drawing with bore, rod (buckling-verified for vertical loading), stroke, FKM seal specification, chrome plating thickness, cushion detail for both open and closed positions, and mounting dimensions. Hydrostatic test at 37.5 MPa + full-stroke functional test. Seal kits. Browse the complete vulcanizing machine cylinder family<\/a>.<\/p>\n<\/div><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

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

Does this cylinder also provide the clamping force during cure?<\/h3>\n

No \u2014 the pressurized cylinder<\/a> (#29) provides the sustained clamping force. This cylinder provides the motion \u2014 lowering the dome onto the container and raising it after cure. The two cylinders work in sequence: this cylinder closes the mold, then the pressurized cylinder applies and holds clamping force for the 10\u201330 minute cure. After cure, the pressurized cylinder releases, then this cylinder opens the mold.<\/p>\n<\/p><\/div>\n

\n

How does this compare to the injection moulding mold opening cylinder (#26)?<\/h3>\n

Same bore range (50\u2013140 mm), same function (open\/close the mold), very different stroke (4,000 mm vs 700 mm) and environment (150\u2013180 \u00b0C vs room temperature). The vulcanizing cylinder uses FKM seals and heavier chrome plating; the injection cylinder uses NBR seals and lighter chrome. The vulcanizing cylinder is buckling-verified for vertical long-stroke duty; the injection cylinder is not (its 700 mm stroke does not create a buckling risk).<\/p>\n<\/p><\/div>\n

\n

Why does the mold need to close slowly at the end?<\/h3>\n

The green tire sitting in the lower container is soft and precisely positioned by the centre mechanism. The dome must descend onto the green tire gently \u2014 aligning the upper sidewall pattern with the lower tread and centering on the bead rings. A fast impact compresses the green tire unevenly, causing air traps (blisters in the cured tire) and misaligned sidewall markings (a cosmetic reject). The cylinder decelerates to a slow approach speed in the last 50\u2013100 mm of closing \u2014 controlled by a cushion or proportional valve \u2014 before the dome contacts the green tire. Browse the full hydraulic cylinder product range<\/a> including forklift cylinders<\/a> and telescopic cylinders<\/a>.<\/p>\n<\/p><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

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":"

Mold opening and closing hydraulic cylinder for vulcanizing machine \u2014 the traverse actuator that raises the upper mold dome away from the lower mold container after vulcanization, creating enough clearance for the loading arm to swing in and remove the cured tire. Stroke up to 4,000 mm \u2014 6\u00d7 longer than the injection moulding mold opening cylinder (#26) \u2014 because the tire is a large 3D object sitting inside a deep mold cavity, and the upper dome must lift far enough to clear the tire plus the loading arm. The pressurized cylinder (#29) provides the clamping force; this cylinder provides the motion. Bore 50\u2013140 mm, 25 MPa, 384 KN. Korea Ever-Power. ISO 9001. OEM & ODM.<\/div>","protected":false},"featured_media":2421,"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-2420","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\/sk\/wp-json\/wp\/v2\/product\/2420","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hydrauliccylindersprice.com\/sk\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/hydrauliccylindersprice.com\/sk\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/sk\/wp-json\/wp\/v2\/comments?post=2420"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/sk\/wp-json\/wp\/v2\/media\/2421"}],"wp:attachment":[{"href":"https:\/\/hydrauliccylindersprice.com\/sk\/wp-json\/wp\/v2\/media?parent=2420"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/sk\/wp-json\/wp\/v2\/product_brand?post=2420"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/sk\/wp-json\/wp\/v2\/product_cat?post=2420"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/sk\/wp-json\/wp\/v2\/product_tag?post=2420"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}