The ________ cylinder construction is used for heavy-duty applications.

• A. Rolled body
• B. Tie-rod
• C. Aluminum
• D. Plastic

Answer: (B)

Heavy-duty hydraulic cylinders need a construction that stays tightly clamped together under big loads. Tie-rod cylinders achieve this by using several strong steel tie rods that run through the end caps and are tightened with nuts, pulling the end caps firmly against the barrel. This external bracing distributes the stresses along the rods and prevents the end caps from pulling away or the barrel from bulging when pressure rises, giving a very rugged, maintainable structure suited to high-force service.

Rolled body designs are also robust, but they rely on a single-piece barrel and different end-cap assembly, which doesn’t provide the same level of external reinforcement under heavy loads. Materials like aluminum or plastic reduce weight but don’t offer the same strength and wear resistance as steel for heavy-duty hydraulic work, so they’re not the typical choice for the most demanding applications.