{"id":2404,"date":"2026-06-30T08:59:01","date_gmt":"2026-06-30T08:59:01","guid":{"rendered":"https:\/\/hydrauliccylindersprice.com\/product\/cement-equipment-roll-over-cylinder\/"},"modified":"2026-06-30T08:59:15","modified_gmt":"2026-06-30T08:59:15","slug":"cement-equipment-roll-over-cylinder","status":"publish","type":"product","link":"https:\/\/hydrauliccylindersprice.com\/tr\/urun\/cement-equipment-roll-over-cylinder\/","title":{"rendered":"Cement Equipment Roll over Cylinder"},"content":{"rendered":"

<\/p>\n

<\/p>\n

\n
\n
\n Cement Equipment<\/span>
\n Roll Over Cylinder<\/span>\n <\/div>\n

6 Metres of Stroke.
A Few Times per Year.
Zero Tolerance for Failure.<\/h2>\n

The grinding cylinders (#20, #21) run 24\/7 with a 500 mm stroke. The roll over cylinder operates a few times a year \u2014 but with a 6,000 mm stroke. It swings the entire grinding roller assembly outward from the mill body for maintenance: roller surface inspection, table liner replacement, and rocker arm bearing service. If this cylinder fails mid-swing, the roller assembly hangs unsupported \u2014 a multi-tonne load suspended at an awkward angle with no easy recovery.<\/p>\n

\n
\n
\u22646,000mm<\/span><\/div>\n
Stroke (12\u00d7 Grinding)<\/div>\n<\/div>\n
\n
1,688 KN<\/div>\n
Max Thrust<\/div>\n<\/div>\n
\n
21MPa<\/span><\/div>\n
Pressure<\/div>\n<\/div>\n
\n
180\u2013320mm<\/span><\/div>\n
Bore<\/div>\n<\/div><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

What “Roll Over” Means \u2014 Swinging 30 Tonnes of Roller Assembly Out of the Mill<\/h2>\n

Inside a vertical roller mill, the grinding rollers are enclosed within the mill housing \u2014 accessible only through inspection doors too small for major maintenance. When the roller surface needs resurfacing (worn rollers are re-welded on site), the table liners need replacing, or the rocker arm bearings need service, the entire roller assembly must be swung outward from the mill body. This operation is called “roll over.”<\/p>\n

The roll over cylinder lifts and swings the grinding roller, its rocker arm, and the roller shaft assembly \u2014 typically 20\u201350 tonnes \u2014 through a large arc on a hinge mechanism mounted on the mill housing. The assembly rotates outward until the roller is fully clear of the mill, accessible at ground level for crane access, welding, and inspection. The 6,000 mm stroke provides the travel needed to swing through this arc \u2014 from the operating position deep inside the mill to the fully-open maintenance position outside it. Korea Ever-Power manufactures roll over cylinders as part of the industrial engineering hydraulic cylinder<\/a> programme for cement equipment.<\/p>\n

\"Cement
\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>\nCement Equipment Roll Over Cylinder<\/td>\n<\/tr>\n
Function<\/td>\nSwing the roller assembly outward for maintenance<\/td>\n<\/tr>\n
Bore Diameter<\/td>\n180 mm \u2013 320 mm<\/td>\n<\/tr>\n
Rod Diameter<\/td>\n110 mm \u2013 170 mm<\/td>\n<\/tr>\n
Stroke<\/td>\n\u2264 6,000 mm (longest in cement range)<\/td>\n<\/tr>\n
Maximum Thrust<\/td>\n1,688 KN (bore 320 mm \/ pressure 21 MPa)<\/td>\n<\/tr>\n
Working Pressure<\/td>\nUp to 21 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

Why 6,000 mm \u2014 The Geometry of a Full Swing-Out<\/h2>\n
\n \"Roll<\/p>\n

The grinding cylinders (#20, #21) need only 500 mm of stroke \u2014 enough to adjust the roller gap by a few centimetres. The roll over cylinder needs 12 times more because it swings the roller assembly through an arc of 60\u201390\u00b0 on a hinge that is 3\u20135 metres from the cylinder attachment point.<\/p>\n

The geometry is a lever-and-pivot arrangement: the roll over hinge is on the mill housing side wall, the cylinder connects to the rocker arm frame at a distance from the hinge, and the roller is at the far end. As the cylinder extends, it pushes the frame outward, rotating the roller assembly around the hinge. The arc length at the cylinder attachment point \u2014 not the arc length at the roller \u2014 determines the cylinder stroke. For a hinge radius of 3 metres and a 90\u00b0 swing, the arc length at the attachment point is approximately \u03c0 \u00d7 3 \/ 2 \u2248 4.7 metres. The 6,000 mm maximum stroke provides margin for larger mill geometries and wider swing angles.<\/p>\n

A 6,000 mm stroke on a 320 mm bore creates a very long, slender cylinder. Buckling resistance is a critical engineering consideration \u2014 the cylinder must be checked for Euler column buckling under the full 1,688 KN load at maximum extension. Korea Ever-Power verifies the buckling safety factor using the specific mounting geometry (pin-to-pin length, mounting angle) for each customer’s mill installation.<\/p>\n<\/p><\/div>\n

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

<\/p>\n

\n

Four Cement Cylinders \u2014 Each Serves a Different Phase<\/h2>\n

Korea Ever-Power manufactures four cylinder types for cement plant equipment. They look like a family, but each operates at a different speed, duty cycle, and purpose within the plant:<\/p>\n

\n\n\n\n\n\n\n\n\n
#<\/th>\nCylinder<\/th>\nStroke<\/th>\nMPa<\/th>\nPurpose<\/th>\nDuty<\/th>\n<\/tr>\n<\/thead>\n
20<\/td>\nRoller Press<\/td>\n\u2264500<\/td>\n14<\/td>\nPush rollers together<\/td>\n24\/7 continuous<\/td>\n<\/tr>\n
21<\/td>\nVertical Mill<\/td>\n\u2264500<\/td>\n14<\/td>\nPress roller onto table<\/td>\n24\/7 continuous<\/td>\n<\/tr>\n
22<\/td>\nRoll Over<\/td>\n\u22646,000<\/td>\n21<\/td>\nSwing roller out<\/td>\nFew times\/year<\/td>\n<\/tr>\n
23<\/td>\nFeeding<\/td>\nTBD<\/td>\nTBD<\/td>\nDrive grate cooler bed<\/td>\nContinuous reciprocating<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n

The roll over cylinder operates the least frequently but carries the highest per-operation risk \u2014 any failure during the swing leaves a multi-tonne assembly in a hazardous intermediate position.<\/p>\n<\/section>\n

<\/p>\n

\n
\n

Engineering Concern \u2014 What Happens if the Cylinder Fails Mid-Swing<\/h2>\n

The roll over cylinder is extended infrequently \u2014 but when it operates, the roller assembly is in transit between two stable positions (closed inside the mill, or fully open outside). At any intermediate position, the assembly’s weight is partially supported by the cylinder and partially by the hinge. If the cylinder loses pressure mid-swing, the assembly’s weight drives it to an uncontrolled position \u2014 either slamming back into the mill or swinging outward under gravity, depending on the hinge geometry.<\/p>\n

\n
\n Load-holding valve \u2014 mandatory<\/strong><\/p>\n

A pilot-operated load-holding valve (counterbalance valve) on the cylinder prevents the roller assembly from moving if hydraulic pressure is lost. The valve locks the oil in the cylinder \u2014 holding the assembly at whatever position it occupied when the failure occurred. The maintenance crew can then bring a mobile hydraulic power unit to complete or reverse the swing safely.<\/p>\n<\/p><\/div>\n

\n Mechanical latch at the open position<\/strong><\/p>\n

Once the roller assembly reaches the fully-open position, a mechanical latch or prop secures it \u2014 transferring the load from the cylinder to the latch. The cylinder can then be depressurised safely. This ensures that maintenance crews working under the swing-out assembly are never relying on hydraulic pressure alone for safety.<\/p>\n<\/p><\/div>\n

\n Slow speed throughout the swing<\/strong><\/p>\n

The roll over operation is performed at low hydraulic flow \u2014 keeping the swing speed slow enough for the operator to stop the motion at any point. Typical swing time for the full 6-metre stroke is 5\u201315 minutes (not seconds). This slow speed ensures controllability and gives the operator time to react to any misalignment, interference, or unexpected load change during the swing.<\/p>\n<\/p><\/div>\n<\/p><\/div>\n

Korea Ever-Power designs every roll over cylinder with load-holding valve provisions, mechanical latch interface details, and slow-speed circuit recommendations as standard deliverables. Contact the hydraulic cylinder engineering team<\/a> for roll over cylinder specifications.<\/p>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n \"Roll
\n<\/section>\n

<\/p>\n

\n

Long-Stroke Engineering \u2014 Buckling, Alignment, and Storage<\/h2>\n
\n \"Korea<\/p>\n

A 6-metre stroke on a 180\u2013320 mm bore creates a cylinder that is extremely long relative to its diameter. This length ratio introduces engineering considerations that short-stroke grinding cylinders never face.<\/p>\n

Euler buckling.<\/strong> At full extension under load, the rod acts as a long, slender column. The critical buckling load must exceed the working thrust by a safety factor of 3:1 or more. Korea Ever-Power selects the rod diameter not only for hydraulic force but for buckling resistance at the specific pin-to-pin distance and mounting angle of each installation \u2014 a rod that is hydraulically adequate may be structurally inadequate if the mounting geometry creates a long unsupported column.<\/p>\n

Rod droop and guide bearing wear.<\/strong> A 6-metre rod extending horizontally from the barrel sags under its own weight. This sag loads the rod guide bearing unevenly \u2014 the bottom of the bearing carries more load than the top. Over time, this asymmetric loading wears the guide bearing into an oval, degrading the rod seal concentricity and eventually causing a leak. Korea Ever-Power specifies oversized guide bearings for long-stroke horizontal installations.<\/p>\n

Long-term storage position.<\/strong> The roll over cylinder spends 99% of its life in the retracted position (roller assembly inside the mill). During this idle period, the retracted rod surface is protected inside the barrel \u2014 but the barrel end and port connections are exposed to cement dust for months. Korea Ever-Power specifies protective port caps and recommends a monthly partial-stroke exercise cycle to circulate oil through the seals and prevent static seal degradation.<\/p>\n<\/p><\/div>\n

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

<\/p>\n

\n

OEM & ODM<\/h2>\n
\n
\n
\n

What You Provide<\/h3>\n<\/div>\n
\n

Roller assembly weight (tonnes), roll over hinge geometry (hinge axis position, cylinder attachment point), required swing angle, pin-to-pin distance at full extension (for buckling calculation), mounting orientation (horizontal, inclined, vertical), load-holding requirement, mechanical latch type, and the mill housing\/rocker arm drawing showing the roll over hinge and cylinder mounting positions.<\/p>\n<\/div><\/div>\n

\n
\n

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

Engineering drawing with bore, rod (buckling-verified for the specific pin-to-pin geometry), stroke, barrel wall thickness, load-holding valve specification, cushion detail for end-of-swing deceleration, oversized guide bearing for horizontal long-stroke duty, and protective port cap detail. Hydrostatic test at 1.5\u00d7 working pressure (31.5 MPa). Seal kits. Browse all cement equipment cylinders<\/a>.<\/p>\n<\/div><\/div>\n<\/p><\/div>\n<\/section>\n

<\/p>\n

\n

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

Why is the pressure 21 MPa \u2014 higher than the grinding cylinders at 14 MPa?<\/h3>\n

The roll over cylinder has a smaller bore (180\u2013320 mm) than the grinding cylinders (200\u2013700 mm) but must still produce enough force to lift and swing the heavy roller assembly. Higher pressure compensates for the smaller bore area. At 320 mm bore and 21 MPa, the thrust is 1,688 KN \u2014 sufficient for the heaviest roller assemblies. A larger bore at lower pressure would achieve the same force but would make the cylinder heavier and longer, worsening the buckling problem.<\/p>\n<\/p><\/div>\n

\n

How often is the roll over cylinder used?<\/h3>\n

Typically 2\u20136 times per year per roller position \u2014 during scheduled maintenance shutdowns. Roller re-welding (the most common maintenance) happens every 2,000\u20134,000 operating hours. Table liner replacement happens annually. Each roll over event involves two full strokes: one to swing the roller out, one to swing it back in after maintenance is complete. Despite the low cycle count, the cylinder must perform reliably every time \u2014 a failure during a scheduled maintenance window delays the mill restart and extends the production shutdown.<\/p>\n<\/p><\/div>\n

\n

Can the roll over cylinder be used for kiln support roller adjustment too?<\/h3>\n

The bore and pressure range overlaps with kiln tyre\/roller adjustment cylinders, but the stroke requirements differ significantly. Kiln support roller adjustment involves short strokes (50\u2013200 mm) at high force \u2014 the opposite of the roll over cylinder’s long stroke requirement. Korea Ever-Power engineers each cylinder for its specific application. For kiln-specific cylinders, contact the industrial engineering cylinder team<\/a>. For long-stroke applications in other industries, see the telescopic cylinder range<\/a> and full product catalogue<\/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":"

Cement equipment roll over cylinder \u2014 the maintenance-access actuator that swings the vertical mill grinding roller and its rocker arm outward from the mill body, giving maintenance crews access to the roller surface, the table liner segments, and the rocker arm bearings. Stroke up to 6,000 mm \u2014 the longest in the cement cylinder range and 12\u00d7 longer than the grinding cylinders (#20, #21). The grinding cylinders operate continuously for 8,000 hours per year; the roll over cylinder operates a few times per year \u2014 but each operation must lift and swing 20\u201350 tonnes of roller assembly through a long arc without failure. Bore 180\u2013320 mm, 21 MPa, thrust 1,688 KN. Korea Ever-Power. ISO 9001. OEM & ODM.<\/div>","protected":false},"featured_media":2405,"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-2404","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\/tr\/wp-json\/wp\/v2\/product\/2404","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hydrauliccylindersprice.com\/tr\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/hydrauliccylindersprice.com\/tr\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/tr\/wp-json\/wp\/v2\/comments?post=2404"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/tr\/wp-json\/wp\/v2\/media\/2405"}],"wp:attachment":[{"href":"https:\/\/hydrauliccylindersprice.com\/tr\/wp-json\/wp\/v2\/media?parent=2404"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/tr\/wp-json\/wp\/v2\/product_brand?post=2404"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/tr\/wp-json\/wp\/v2\/product_cat?post=2404"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/tr\/wp-json\/wp\/v2\/product_tag?post=2404"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}