Sandvik 152 254 88 Diaphragm

The diaphragm, part 152 254 88, usually announces its failure through the symptoms of the system it sits in, not through anything visible on the part itself. When the membrane ruptures, the two media it was keeping apart start to mix, so the first signs tend to be pressure that no longer holds, a response that has become erratic, or fluid showing up on the side where it should never be.

Because those symptoms can also come from a valve or a seal, it is worth ruling out the cheaper causes first and then confirming the diaphragm by checking whether the system recovers after it is replaced. Once the housing is open, look for traces of the wrong fluid on the dry side and for any foreign particles trapped against the membrane, since debris is a common reason a new diaphragm fails early. Store spares flat and away from sunlight and ozone, which age elastomers on the shelf as well as in the machine. Stalroc quotes this Sandvik reference by part number and exports worldwide to mining, quarrying, and drilling contractors.