Two Kinds of Hydraulic Manifolds, Part II: Modular Manifolds

In Part I, we discussed the benefits of one of the two major types of hydraulic manifolds— the ‘single-piece’ manfolds, laminar and drilled-block. Today, we’re going to talk about the other major kind of manifold: the ‘modular’ manifold.

Modular manifolds have a single massive advantage over single-piece manifolds: they can be changed on the fly as the job evolves. Sometimes called the ‘erector set approach,’ modular manifolds involves a few to scores of iron, steel, or aluminum blocks, each of which has a single valve or other operator inside. Modular manifold systems can be assembled horizontally or stacked.

Most often, plates are installed between the basic ‘building block’ components to make for regular spacing and to allow for small variations in the location and size of intake and outflow passages.

The method by which the manifold blocks are connected varies by builder. Some use rods that extend through the length of the manifold and are secured on either end with nuts. Others have flanges on every block so they can be bolted together one at a time. Still others have sockets and threaded heads alongside the hydraulic passages inside each block that snap together. No matter how the blocks are connected, every block has an O-ring around every passage entering or exiting it that abuts the O-ring on the adjacent block for the purpose of forming a seal.

Most such blocks also have the necessary electrical connections built into the blocks, connecting the machinery to the appropriate solenoid. Some instead utilize channels that allow for runs of standard electric cable instead.

The limitations of modular manifolds are more dramatic than those of single-block manifolds. Internal pressure, flow rate, and the length of an individual manifold are all much more sensitive in a modular manifold than they are in a single-piece manifold.

Hydraulic manifolds are amazing tools, able to replace as much as 300 lbs of tubing and valves in as little as a single cubic foot of space. Compared to the tubing and valve setup, a manifold can cost two-thirds to half as much to assemble and install, save a mountain of space, and require only a single hydraulic filter to keep the fluid running smoothly. Whether you choose drilled-block, laminar, or modular manifolds, you’re certain to appreciate the advantages.