A sand rammer, also known as a sand ramming machine or a sand compaction hammer, is a tool or machine used in foundry and construction applications to compact sand in molds or other types of sand-filled containers.

It is commonly used in foundries for preparing sand molds used in casting processes.

The sand rammer typically consists of a heavy metal head or ram that is lifted and dropped repeatedly onto the sand surface to compact it. The ram may be pneumatically powered or operated manually. The compaction achieved by the sand rammer helps to create a dense and uniform sand mold, which is essential for producing high-quality castings with precise dimensions and smooth surfaces.

Sand rammers come in various sizes and designs, including handheld portable models for small-scale applications, as well as larger, floor-mounted models for heavy-duty use in foundries. They may have different types of heads or tips, such as flat, conical, or bar-shaped, depending on the specific application and desired compaction characteristics.

Sand ramming is an important step in the foundry process as it ensures that the sand molds are properly compacted, which helps in achieving good mold strength, dimensional accuracy, and surface finish in the final castings. Sand rammers are also used in construction and geotechnical engineering for soil compaction testing or in other applications where sand compaction is required.