When to Choose Ductile Steel vs. Aluminum Hydraulic Manifold Body

By Tom Eystad, CFPS

Choosing between ductile steel and aluminum can mean the difference between a failed product or machine and a reliable, productive machine. Consider the following factors:

System Pressures

When system pressure will be consistently above 3500 psi, ductile steel is required. Also, when normal operating pressures are at or near or at 3500 psi, and when pressure “spikes” might exceed 3500 psi, ductile steel should be considered.


Corrosive environments can also affect the material requirements of the manifold or body. Typically aluminum is anodized and ductile steel is plated; the plating provides a level of protection against corrosion. Consideration must be given to which is best for the environment.

Duty Cycle

Duty cycle of the system or function can also affect the manifold or body material requirement. High pulse applications, machine vibration and continuous severe duty cycles are all factors for consideration for using ductile or steel over aluminum.


Generally, aluminum is less costly due to lower material cost and ease of machining.

All of these considerations should be evaluated in your decision to use aluminum or ductile steel. The final choice will directly impact system reliability and machine uptime.

Contact Quality Hydraulics & Pneumatics, Inc. for custom hydraulic manifolds, hydraulic and pneumatic component sales, customer service and certified support. Phone: (847) 680-8400 Fax: (847) 680-5325 E-mail: info@qualityhydraulics.com