Leaky fittings are a cause for concern in hydraulic circuits especially with increase in the number of connections. This is where manifolds play a very important role. Their incorporation in a hydraulic circuit helps drastically reduce the number of external connections required. Figure 6.50 shows a simple manifold commonly employed in hydraulic systems.
In the case of modular valve stacking, the manifolds used are provided with common pressure and return ports, with each valve station being incorporated with individual A and B work ports. Manifolds are normally specified according to system pressure, total flow, number of work stations and valve size and pattern.