Foundry Sands — Name the Sand Dusted on Pattern Faces In moulding practice, which sand is sprinkled on the faces of the pattern before ramming the mould to prevent sticking and facilitate clean withdrawal?

Introduction / Context:
During mould making, patterns must be withdrawn without tearing the mould surface. A fine, non-sticky sand is often dusted onto the pattern to act as a release agent and ensure a clean separation.

Given Data / Assumptions:

• Moulding with patterns in sand.
• Objective: minimize adhesion between pattern and mould.
• Need: ease of withdrawal and surface integrity.

Concept / Approach:
Parting sand is dry, fine sand (or proprietary parting compounds) used as a thin layer on the pattern surface or parting plane to prevent sticking. It reduces shear during draw and protects delicate features of the mould cavity.

Step-by-Step Solution:
Identify the function: release agent on pattern faces.Recall terminology: parting sand performs this role.Exclude other sands: green/dry/backing sands describe mould composition, not release dusting.Select parting sand.

Verification / Alternative check:
Foundry handbooks list parting sand or powders used at parting planes and on pattern surfaces.

Why Other Options Are Wrong:
Green/dry/backing sand: bulk mould materials.Loam sand: used for loam moulds, not as a dusting agent.

Common Pitfalls:
Overusing parting compound can cause surface defects; apply sparingly and evenly.

Final Answer:
parting sand