Gravity vs Sand Casting: RFQ Process Guide for Aluminum

# Gravity Casting vs Sand Casting: Buyer Process Selection Guide

Gravity casting and sand casting can both produce useful aluminum parts, but they serve different buyer situations. The best process depends on volume, geometry, tooling budget, surface expectations, machining stock, inspection requirements, and how stable the design is.

This guide helps OEM buyers decide which route to discuss in an RFQ.

When gravity casting fits

Gravity casting is often a strong candidate when the part has repeat demand, stable geometry, moderate to high annual volume, better surface expectations, tighter repeatability needs, and a clear path to permanent tooling. It can be useful for housings, brackets, covers, pump parts, valve bodies, and other engineered aluminum parts when the tooling investment is justified.

When sand casting fits

Sand casting can be useful for large parts, low-volume programs, early design validation, complex shapes that do not justify permanent tooling, and situations where design changes are still likely. It may carry different surface, tolerance, and machining-stock assumptions, so buyers should define acceptance criteria clearly.

RFQ comparison questions

Ask suppliers to explain:

• •process route and why it fits the part
• •tooling cost, ownership, and revision process
• •sample approval path
• •expected tolerance and machining stock
• •surface finish and finishing assumptions
• •inspection records needed for buyer approval
• •cost and lead-time assumptions at current and future volume

Avoid process-name shopping

Do not choose a supplier only because it offers one process name. A credible supplier should explain tradeoffs and may recommend a different route after reviewing the drawing, volume, material, machining, and quality requirements.

Bohua RFQ path

Bohua can review gravity casting vs sand casting decisions for aluminum RFQs, including tooling path, sample approval, inspection scope, and quote comparison assumptions. Send drawings and volume expectations through the formal RFQ form when the process decision needs supplier input.