Inserts are used in a variety of applications to seal, restrict or otherwise modify holes in systems such as hydraulic or engine systems. These inserts vary in size and depending on the application, there may be multiple inserts needed to provide a properly sealed manifold.
In the example of hydraulic manifolds, there are numerous holes provided during machining that may be used to carve out internal passageways within the block. These holes may vary in size such that different insert sizes are needed to seal the holes after machining operations are completed.
Manifolds will often have other passages that are not to be sealed. For example, hydraulic hoses and other lines or parts may be threaded or otherwise attached to the manifolds so that fluid can flow within the passages.
The inserts used to seal the appropriate holes in the manifold are often small and can sometimes fall into the passages. The operator must then rotate the block or somehow retrieve the insert from the passage, which can cause delays.
Since the size of the holes may vary, sometimes the wrong insert is placed in the wrong hole due to relatively close sizes. Since hydraulic manifolds often operate under high pressure, improper selection of inserts could result in a seal that cannot withstand the appropriate pressures.
As yet another concern, once the inserts are placed in the appropriate holes, they must be expanded. In some cases, this is done with an air hammer. The hammer is typically intended be used to install or expand the insert without damaging the manifold. In some cases, operators will miss the insert and damage the manifold to the point where it must be discarded or recycled. Since the manifold has undergone complicated machining processes prior to the installation of inserts, damage to the manifold at the later stages can cause significant waste of resources and money.