Cylinders allow hydraulic systems to apply linear motion and force without mechanical gears or levers by transferring the pressure from fluid via a piston to the point of 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, in comparison to pneumatic, mechanical or electric systems, hydraulics can be simpler, more durable, and provides greater power. For example, Petrol Engine Hydraulic Pump has about ten times the power density of an motor unit of similar size. Hydraulic cylinders can be found in an impressive array of scales to meet a variety of application requirements.
Selecting the right cylinder to have an application is crucial 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 common cylinder configurations are tie-rod, welded and ram styles. Tie-rod cylinders use high-strength threaded steel tie-rods, typically on the outside the cylinder housing, to provide additional stability. Welded cylinders come with a heavy-duty welded cylinder housing having a barrel welded directly to the final caps, and require no tie rods. Ram cylinders are just what they sound like-the cylinder pushes straight ahead using high pressure. Ram cylinders are utilized in heavy-duty applications and almost always push loads instead of pull.
For all sorts of cylinders, the crucial measurements include stroke, bore diameter and rod diameter. Stroke lengths differ from less than an inch to many feet or even more. Bore diameters can vary from an inch up to a lot more than 24 in., and piston rod diameters vary from .5 in. to a lot more than 20 in. In reality, however, deciding on a stroke, bore and rod dimensions might be limited by environmental or design conditions. For example, space might be too limited for that ideal stroke length. For tie-rod cylinders, increasing the dimensions of the bore means increasing the amount of tie rods necessary to retain stability. Enhancing the diameter in the bore or piston rod is a perfect way to make amends for higher loads, but space considerations may not allow this, in which case multiple cylinders is usually necessary.
Mounting methods also play a vital role in cylinder performance. Generally, fixed mounts on the centerline from the cylinder are ideal for straight line force transfer and avoiding wear. Common types of mounting include:
Flange mounts-Very 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-Simple to install and repair, however the mounts produce a turning moment since the cylinder applies force to a load, increasing deterioration. To avoid this, specify a stroke at the very least as long as the bore size for side mount cylinders (heavy loading is likely 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 avoid movement at higher pressures or under shock conditions. Pivot mounts -Absorb force on the cylinder centerline and enable the cylinder change alignment in one 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 which pivot. Clevis mounts may be used in every orientation and tend to be suitable for short strokes and small- to medium-bore cylinders.
Operating conditions-Cylinders must match a particular application with regards to the amount of pressure (psi), force exerted, space requirements imposed by machine design, and the like. But knowing the operating requirements is just half the challenge. Cylinders also must withstand high temperatures, humidity and even salt water for Air Driven Hydraulic Pump. 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 compared to they appear at first glance.
Fluid type-Most hydraulics use a kind of mineral oil, but applications involving synthetic fluids, including phosphate esters, require Viton seals. Once more, Buna-N seals may not be adequate to handle synthetic fluid hydraulics. Polyurethane is also incompatible with higher water-based fluids including water glycol.
Seals -This is among the most vulnerable part of Rubber Hydraulic Hose. Proper seals is able to reduce friction and wear, lengthening service life, while the wrong kind of seal can cause downtime and maintenance headaches.
Cylinder materials -The type of metal utilized for cylinder head, base and bearing can create a significant difference. Most cylinders use SAE 660 bronze for rod bearings and medium-grade carbon steel for heads and bases, that is adequate for most applications. But stronger materials, including 65-45-12 ductile iron for rod bearings, can offer a sizable performance rldvub for tough industrial tasks. The type of piston rod material could be crucial in wet or high-humidity environments (e.g., marine hydraulics) where17-4PH stainless-steel might 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