Short answer
Spec a welded cylinder when the job is high-pressure, high-shock, tight on space, or mobile — the barrel is welded directly to the end cap, so it is compact and rugged. Spec a tie-rod cylinder when you want a bolt-together design that follows NFPA interchange dimensions and comes apart for field service, typical of industrial and lower-pressure work. Both are built to the same print discipline; the construction method is the real difference.
What is the difference between welded and tie-rod cylinders?
A tie-rod cylinder holds its end caps onto the barrel with several high-strength threaded rods running the full length of the cylinder, torqued at the ends. A welded cylinder skips the tie rods entirely: the end caps and mounts are welded straight to the barrel tube, making it one integral steel assembly.
That single construction choice drives everything else. Tie-rod cylinders are modular and follow published NFPA interchange dimensions, so parts and mounts are standardized across makers. Welded cylinders are compact and take higher pressure and shock, which is why they dominate mobile and heavy equipment.
When should you choose a welded cylinder?
Choose welded construction for high working pressures, heavy shock loading, side loads, and applications where space is tight — the welded barrel has no protruding tie rods, so the outside diameter is smaller for the same bore. That compactness and toughness is why welded cylinders are standard on excavators, loaders, dump trailers, forestry grapples, and other mobile equipment.
Welded cylinders also handle the high end of the pressure range comfortably; WestCraft designs to pressures up to 10,000 PSI. If the machine sees impact, dirt, and duty cycles measured in the hundreds of thousands, welded is usually the right call.
When should you choose a tie-rod cylinder?
Choose tie-rod construction for industrial and factory applications at more moderate pressures, especially where you want a design that follows NFPA interchange dimensions so mounts and dimensions are standardized. Because the ends bolt on, a tie-rod cylinder comes apart on the bench for reseal and service without cutting any welds.
Tie-rod cylinders suit presses, clamps, material-handling equipment, and machinery mounted in a fixed, guided, in-line arrangement. The trade-off is size and shock tolerance: the tie rods add outside envelope and can stretch under heavy impact loading, which is exactly where welded pulls ahead.
Which construction is easier to repair?
Both are repairable. A tie-rod cylinder is designed to be taken apart — loosen the tie-rod nuts, slide the caps off, reseal, and reassemble — so it is the more field-serviceable of the two. A welded cylinder is opened by removing the gland (rod-end cap), which threads or bolts in; the barrel weld itself is not disturbed during a normal reseal.
In practice a well-built welded cylinder is rebuilt just as routinely as a tie-rod unit — new seals, hone the bore, re-chrome or replace the rod as needed. The construction affects how it comes apart, not whether it can be rebuilt.