Cylinders allow hydraulic systems to use linear motion and force without mechanical gears or levers by transferring the pressure from fluid by way of a piston to begin operation. Hydraulic cylinders are at work in both industrial applications (hydraulic presses, cranes, forges, packing machines), and mobile applications (agricultural machines, construction equipment, marine equipment). And, when compared with pneumatic, mechanical or electric systems, hydraulics could be simpler, stronger, and offer greater power. For example, Welded Hydraulic Cylinders With Steel Cylinder has about ten times the power density of an motor unit of similar size. Hydraulic cylinders are also available in a remarkable variety of scales to meet an array of application needs.
Choosing the right cylinder for an application is essential to attaining maximum performance and reliability. That means considering several parameters. Fortunately, a variety of cylinder types, mounting techniques and “rules of thumb” are offered to help.
The 3 most frequent cylinder configurations are tie-rod, welded and ram styles. Tie-rod cylinders use high-strength threaded steel tie-rods, typically on the outside of the cylinder housing, to supply additional stability. Welded cylinders come with a heavy-duty welded cylinder housing using a barrel welded directly to the final caps, and require no tie rods. Ram cylinders are simply whatever they sound like-the cylinder pushes straight ahead using extremely high pressure. Ram cylinders are utilized in heavy-duty applications and typically push loads as opposed to pull.
For all types of cylinders, the crucial measurements include stroke, bore diameter and rod diameter. Stroke lengths vary from under an inch to many feet or even more. Bore diameters may range from an inch up to greater than 24 in., and piston rod diameters vary from .5 in. to more than 20 in. In practice, however, the choice of stroke, bore and rod dimensions might be limited by environmental or design conditions. As an example, space could be too limited for that ideal stroke length. For tie-rod cylinders, increasing the size of the bore does mean increasing the number of tie rods needed to retain stability. Enhancing the diameter in the bore or piston rod is a great method to make up for higher loads, but space considerations may not allow this, whereby multiple cylinders may be required.
Mounting methods also play a vital role in cylinder performance. Generally, fixed mounts on the centerline from the cylinder are perfect for straight line force transfer and avoiding wear. Common varieties of mounting include:
Flange mounts-Quite strong and rigid, but have little tolerance for misalignment. Experts recommend cap end mounts for thrust loads and rod end mounts where major loading puts the piston rod in tension. Side-mounted cylinders-Easy to install and service, but the mounts produce a turning moment because the cylinder applies force to a load, increasing deterioration. To avert this, specify a stroke at least provided that the bore size for side mount cylinders (heavy loading tends to make short stroke, large bore cylinders unstable). Side mounts need to be well aligned as well as the load supported and guided.
Centerline lug mounts -Absorb forces on the centerline, but require dowel pins to secure the lugs to prevent movement at higher pressures or under shock conditions. Pivot mounts -Absorb force on the cylinder centerline and let the cylinder change alignment in a single plane. Common types include clevises, trunnion mounts and spherical bearings. Because these mounts allow a cylinder to pivot, they must be used in combination with rod-end attachments that also pivot. Clevis mounts can be utilized in any orientation and tend to be suitable for short strokes and small- to medium-bore cylinders.
Operating conditions-Cylinders must match a certain application with regards to the quantity of pressure (psi), force exerted, space requirements imposed by machine design, and so forth. But understanding the operating requirements is only half the process. Cylinders should also withstand high temperatures, humidity and also salt water for Digital Direct Proportional Valve. Wherever temperatures typically rise to greater than 300° F, standard Buna-N nitrile rubber seals may fail-choose cylinders with Viton synthetic rubber seals instead. If in doubt, assume operating conditions will be more rugged than they appear at first glance.
Fluid type-Most hydraulics use a form of mineral oil, but applications involving synthetic fluids, like phosphate esters, require Viton seals. Yet again, Buna-N seals may not be adequate to deal with synthetic fluid hydraulics. Polyurethane can also be incompatible with high water-based fluids including water glycol.
Seals -This has become the most vulnerable part of Cylinder Piston Small. Proper seals can reduce friction and wear, lengthening service life, whilst the wrong kind of seal can cause downtime and maintenance headaches.
Cylinder materials -The type of metal used for cylinder head, base and bearing can easily make a significant difference. Most cylinders use SAE 660 bronze for rod bearings and medium-grade carbon steel for heads and bases, which can be adequate for many applications. But stronger materials, such as 65-45-12 ductile iron for rod bearings, can provide a sizable performance rldvub for tough industrial tasks. The kind of piston rod material can be crucial in wet or high-humidity environments (e.g., marine hydraulics) where17-4PH stainless steel may be stronger compared to the standard case-hardened carbon steel with chrome plating used for most piston rods.
Yongxiang Hydraulic Equipment Co., Ltd locates in Yangzhou, CN, and it covers an area of 143,500 square feet. Winning customer trust with innovation, Yongxiang has been aiming to provide customers with safe and reliable hydraulic products, services, on-time delivery, and customer satisfaction while ensuring employee safety, fostering employee relations and driving efficiency improvements.
Jiangsu Yongxiang Hydraulic Equipment Co. Ltd
Factory: Wujian Industrial Park, Jiangdu District, Yangzhou, CN
Office: 3107# No.2 Building, Global Financial Center, Wenchang East Road, Yangzhou, CN