By Todd Lewis
Hydraulic cylinders are known to be one of the most useful and practical fluid power components available. Because of this, they have evolved into countless arrays of designs, sizes, and configurations. Two popular classes of hydraulic cylinders include tie-rod cylinders and welded cylinders. How do you know which is right for your use case? There are certain considerations to keep in mind including the bore size, rod size, and stroke length.
The bore size refers to the inside diameter of the cylinder while the rod size is the piston rod’s diameter. The stroke is the distance that the piston travels between the fully retracted and fully extended positions. When it comes to repairing hydraulic cylinders, it’s important to find a trustworthy and experienced team.
Welded hydraulic cylinders have a more complex design compared with tie rod cylinders as one cap is typically welded directly to barrel and the other cap is threaded or locked on the barrel. In this design, the mounts and other cylinder fittings are also welded directly to the cylinder. Welded hydraulic cylinders are ultimately designed and constructed to be as durable as possible as they are most commonly used in harsh environments. Because they are so durable and can be reopened, they have a longer lifespan compared with other types of cylinders.
This type of cylinder has a lightweight and compact design combined with higher pressure capabilities that make them ideal for mobile equipment. Keep in mind that repairing this type of cylinder requires different tools and can be more challenging to repair.
Tie rod cylinders are another cylinder variety. They have threaded tie bolts or rods that extend the length of the cylinder tube, passing through holes in the cylinder end caps. The rods are held in place with a nut to secure the end caps to the cylinder barrel. How many threaded tie bolts there are depend on the diameter of the bore in addition to the operating pressure, but the number ranges from 4 to 20.
When it comes to tie rod cylinders vs. welded cylinders, the ease of maintenance for tie rod cylinders is a noteworthy factor. Even conventional tools can easily assemble and disassemble tie rod cylinders, however, they require additional installation space compared with welded cylinders solely based on the bulkier design. This cylinder variety is also built to NFPA standards.
If you are using tie rods to connect cylinders, it’s possible to unbolt them to take apart the cylinder. This is particularly helpful if you need to make a repair. However, opting for a welded cylinder design doesn’t mean you have a “throw away” cylinder; if they need to be repaired, it’s easy to take them apart as the seals and rods are typically designed to be easily taken off without removing the end caps.
Durability issues also come into play. Using welded hydraulic cylinders means you don’t have to worry about durability, however, there are some high-pressure and extended use cases that can result in the tie rods stretching on cylinders that are bolted together. This typically ends in failure and downtime, something that many businesses cannot afford to incur.
It can be difficult to determine whether to use a welded hydraulic cylinder or a tie rod cylinder.
You should use the welded body cylinder if:
You should choose the tie-rod cylinder if:
We hope this clears up any confusion about these two types of cylinders. Navigating the use cases and differences between welded cylinders and tie rod cylinders is easy with the right team on your side. At Cylinders, Inc., our professional team specializes in cylinders and we’re happy to help you choose the right one for your application. In the case that you need a reliable and trustworthy hydraulic cylinder repair company, we are your go-to resource! Contact us today to see how our experts can assist you with your cylinder needs.
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