Manufacturing Process
Sand Casting.
Three Variants.
One Partner.
Green Sand for volume ferrous production. No-Bake for large, complex, dimensionally critical castings. Steel Sand for structural steel, alloy steel, and manganese grades. All backed by in-house CMM, spectrometer, and 40+ years of foundry expertise.
Green Sand Casting
0.5–500kg
Weight Range
CT8–10
ISO 8062 Tolerance
50–50K
Volume / Year
4mm
Min Wall Thickness
Materials
GG20GG25
GG30GGG40
GGG50GGG60
No-Bake / Furan Resin Casting
1–1000kg
Weight Range
CT7–9
ISO 8062 Tolerance
10–5K
Volume / Year
3mm
Min Wall Thickness
Materials
Grey IronDuctile Iron
Carbon SteelAlloy Steel
SS 304/316
Steel Sand Casting
0.5–1000kg
Weight Range
CT8–11
ISO 8062 Tolerance
450+MPa
Tensile (WCB)
Q&T
Heat Treatment
Materials
WCA/WCBLCC
4140/EN24Hadfield Mn
H13
Process Explained
How Each Process Works
Three distinct sand casting processes — each optimised for different geometries, volumes, and material grades. Understanding the differences helps you choose the right one for your component.
01
Pattern Preparation
Wood, resin, or metal pattern is prepared — an exact replica of the component geometry. Draft angles, parting line, and gating system are designed by Amsol's casting engineers.
02
Moulding
Silica sand mixed with bentonite clay and water is packed around the pattern. The pattern is withdrawn, leaving a cavity. Called "green" because the sand remains moist — not because of colour.
03
Pouring
Molten metal (1,200–1,400°C for grey/ductile iron) is poured into the mould cavity through the gating system. Solidification begins immediately.
04
Shakeout & Cleaning
After controlled cooling, the sand mould is broken away. Casting is shot-blasted, gates and feeders removed, and surface prepared for inspection or machining.
05
Inspection & Despatch
Spectrometer material verification. CMM dimensional inspection on critical features. Hardness testing. PPAP documentation where required. Despatch with MTC.
| Green Sand — Full Specification | |
|---|---|
| Weight Range | 0.5 kg – 500 kg (up to 1,000 kg select configs) |
| Dimensional Tolerance | ISO 8062 CT8–CT10 standard · CT6–CT7 with metal pattern |
| Surface Finish (as-cast) | Ra 12.5–25 µm · Ra 3.2–6.3 µm after shot blasting |
| Min Wall Thickness | 4mm minimum · 6–8mm recommended for iron |
| Draft Angle | 1°–3° standard · 0.5° with precision pattern |
| Optimal Volume | 50 – 50,000 pieces/year |
| Tooling Cost | Lowest of all casting processes |
| Lead Time (first article) | 4–6 weeks from approved drawing |
01
Pattern & Core Box Setup
Pattern and core boxes prepared. No-bake allows complex cores for internal passages — a major advantage over green sand. Core assembly planned as part of DFM review.
02
Resin-Bonded Sand Mixing
Silica sand is mixed with furan resin and acid catalyst. The chemical reaction begins on contact. Sand is packed around the pattern while still workable (typically 5–15 minutes).
03
Hardening (Air-Set)
Resin cures at room temperature — no baking required (hence "no-bake"). Produces a rigid mould significantly harder and more dimensionally stable than green sand. Core assembly completed.
04
Pouring & Solidification
Metal poured at appropriate temperature for the alloy. Rigid mould resists metal pressure better than green sand — better dimensional accuracy, less distortion during solidification.
05
Knockout, NDT & Inspection
Mould broken away. For steel castings: UT internal soundness inspection and MT surface inspection available. CMM dimensional verification. MTC from in-house spectrometer.
| No-Bake / Furan — Full Specification | |
|---|---|
| Weight Range | 1 kg – 1,000 kg · ideal 5 kg – 500 kg |
| Dimensional Tolerance | ISO 8062 CT7–CT9 · CT5–CT6 with precision pattern |
| Surface Finish (as-cast) | Ra 6.3–12.5 µm · significantly better than green sand |
| Min Wall Thickness | 3mm minimum · thin-wall with furan cores |
| Core Complexity | Complex internal passages · blind holes · undercuts |
| Optimal Volume | 10 – 5,000 pieces/year |
| Materials | Grey iron · Ductile iron · Carbon steel · Alloy steel · Manganese steel · Stainless steel |
| Lead Time (first article) | 5–8 weeks from approved drawing |
01
Alloy Selection & DFM
Steel castings require careful alloy selection — WCB for general pressure service, LCC for sub-zero, 4140 for high-stress. Amsol's engineers confirm grade and DFM before pattern development.
02
No-Bake Moulding (preferred for steel)
Steel pours at 1,550–1,650°C — significantly hotter than iron. No-bake resin moulds withstand this better than green sand. Risering and feeding system carefully designed to manage shrinkage.
03
Pouring & Controlled Cooling
Steel poured at 1,600°C+. Solidification controlled to minimise hot tears and porosity. Feeding system compensates for steel's higher shrinkage vs iron (2% vs 1%).
04
Heat Treatment
Steel castings are normalised, annealed, or quenched and tempered depending on grade and specification. Q&T to Brinell 300+ achievable. Heat treatment certificate provided.
05
NDT & Full Documentation
UT for internal soundness. MT for surface defects. RT on critical areas on request. Pressure testing for pressure-containing components. Full MTC with chemical + mechanical properties.
| Steel Sand — Full Specification | |
|---|---|
| Weight Range | 0.5 kg – 1,000 kg |
| Tensile Strength Range | 450 MPa (WCA) – 1,000+ MPa (alloy steel Q&T) |
| Dimensional Tolerance | ISO 8062 CT8–CT11 (steel requires more allowance than iron) |
| Heat Treatment | Normalise · Anneal · Q&T · Case hardening available |
| Hardness (Q&T) | Brinell 200–400 HB depending on grade and temper |
| NDT Available | UT · MT · RT · Pressure test |
| Optimal Volume | 10 – 20,000 pieces/year |
| Lead Time (first article) | 6–10 weeks from approved drawing |
Process Selection
Choosing the Right Sand Casting Variant
The wrong process selection is the most expensive mistake in casting. This table helps you identify which variant fits your component — or tell us and Amsol's engineers will recommend.
| Parameter | 🔵 Green Sand | 🟢 No-Bake / Furan | 🟣 Steel Sand |
|---|---|---|---|
| Weight range | 0.5 – 500 kg | 1 – 1,000 kg | 0.5 – 1,000 kg |
| Dimensional tolerance | CT8–CT10 | CT7–CT9 (better) | CT8–CT11 |
| Surface finish as-cast | Ra 12.5–25 µm | Ra 6.3–12.5 µm | Ra 12.5–25 µm |
| Internal cores | Limited — simple only | Complex cores — highlight advantage | Complex cores via no-bake |
| Materials | Grey iron, ductile iron, aluminium | Iron, steel, alloy steel, SS, manganese | Carbon steel, alloy steel, manganese, SS |
| Optimal volume | 50–50,000 / year | 10–5,000 / year | 10–20,000 / year |
| Tooling cost | Lowest | Low–medium | Medium |
| NDT capability | Hardness, spectrometer | UT, MT, spectrometer | UT, MT, RT, pressure test |
| Best for | High-volume ferrous housings, frames, covers | Complex large castings needing accuracy | Pressure-rated, structural, wear-critical steel |
Material Capability
Materials Amsol Works With
Every material is verified by Amsol's in-house optical emission spectrometer before machining begins. Chemical composition confirmed per heat. MTC provided with every shipment.
Grey Cast Iron
GG15 · GG20 · GG25 · GG30 / IS 210
Good machinability · vibration damping · compressive strength · cost-effective at volume
Machine tool beds · pump bodies · engine blocks · gear covers · housings
Ductile / SG Iron
GGG40 · GGG50 · GGG60 · GGG70 / ASTM A536
Higher tensile and yield strength than grey iron · good elongation · nodular graphite structure
Automotive crankshafts · gearbox housings · agricultural frames · differential cases
Carbon Steel
WCA / WCB / C45 / IS 1030 / ASTM A216
Weldable · good toughness · heat-treatable · pressure service capability to ASTM B16.34
Valve bodies · pump casings · structural components · pressure vessels
Low Temperature Steel
LCC / LCB / ASTM A352
Sub-zero impact toughness · Charpy tested · pipeline and cryogenic service
Pipeline valves · LNG fittings · sub-zero pressure service
Alloy Steel
4140 · 4340 · EN24 · WC6 · WC9
High tensile strength · Q&T to Brinell 300+ · fatigue resistance · high-temperature service
Mining equipment · forging dies · structural components · high-temp valves
Manganese Steel (Hadfield)
12–14% Mn / ASTM A128
Work-hardens under impact — the harder it is hit, the harder it gets · extreme wear resistance
Crusher liners · excavator bucket teeth · railway crossings · ball mill liners
Decision Guide
When To Choose Each Variant
If you are unsure which process fits your component, share the drawing — Amsol's engineers will recommend the right variant based on geometry, material, volume, and tolerance requirements.
Choose Green Sand When
Best fit conditions
Component weight is 0.5–500 kg in grey iron or ductile iron
Volume is 50–50,000 pieces/year
Dimensional tolerance CT8–CT10 is acceptable
Budget for tooling is limited — lowest tooling cost
Geometry is moderate — no complex internal passages
Surface finish will be machined on critical faces
Choose No-Bake When
Best fit conditions
Component has complex internal passages requiring cored geometry
Weight exceeds 50 kg — large castings benefit from rigid mould
Better dimensional accuracy needed than green sand provides
Material is steel, alloy steel, or stainless steel
Surface finish Ra 6.3 µm required as-cast
Volume is 10–5,000/year (too low for die casting investment)
Choose Steel Sand When
Best fit conditions
Material must be carbon steel, alloy steel, or manganese steel
Component carries structural or pressure-containing loads
Heat treatment is required — Q&T, normalise, or anneal
NDT is required — UT, MT, RT, or pressure testing
Component needs to be weldable — steel welds, iron does not
Extreme wear is the primary failure mode — manganese steel option
Industry Applications
Who Uses Amsol's Sand Castings
Eight industries. One process family. Hundreds of components shipped from Rajkot to OEMs across North America, Europe, the Middle East, and beyond.
Railways
Coupler components · brake gear housings · bogie frames · structural brackets — DI and alloy steel
Construction & Mining
Crusher liners (Mn steel) · excavator components · bucket teeth · machine frames — No-bake and steel sand
Agriculture
Tractor gearbox housings · PTO components · implement frames · counterweights — Green sand GI/DI
Pumps & Valves
Pump bodies (WCB/LCC) · valve bodies · manifolds · impeller casings — No-bake steel sand
Oil & Gas
Gate/globe valve bodies (WCB/LCC) · flanges · pressure vessels — Steel sand + full NDT + MTC
Infrastructure
Manhole covers (EN 124) · drain grates · cable protection · pipe fittings — Green sand GGG50
Power Transmission
Gearbox housings · bearing housings · reducer cases · motor frames — Green sand / No-bake GI/DI
General Machinery
Machine tool beds · press frames · compressor housings · equipment bases — any grade, any variant
Quality Assurance
What Leaves Amsol Is What the Drawing Says.
Every sand casting is verified at Amsol before dispatch. Not estimated from process parameters. Not assumed from past history. Measured — and documented.
Spectrometer Material Verification
In-house optical emission spectrometer (NABL-aligned) verifies chemical composition of every heat before machining begins. GG25 is GG25 — not assumed, confirmed. MTC issued from our own measurement.
CMM Dimensional Inspection
3D coordinate measuring machine verifies all critical dimensions on every production batch. CMM report provided — balloon numbers against drawing callouts. Not outsourced. In-house at Amsol.
Hardness Testing per Batch
Brinell hardness testing confirms material grade and heat treatment results on every batch. Results recorded and reported with every shipment. Confirms Q&T or normalising was effective.
NDT — UT · MT · RT
Ultrasonic testing for internal soundness, magnetic particle inspection for surface defects, and radiographic testing for critical areas — available on steel sand castings where specified.
PPAP Level 3 Documentation
Full PPAP packages generated from real data: CMM measurements, PFMEA, Control Plan, Cpk/Ppk studies, material certifications, and Part Submission Warrant. Accepted by automotive and OEM quality teams globally.
ISO 9001:2015 Certified
Amsol's ISO 9001:2015 quality management system covers every sand casting process — documented procedures, controlled process parameters, non-conformance management, and annual third-party audit.
Have a Sand Casting
Component? Let's Talk.
Share your drawing. Amsol's casting engineers will recommend the right variant — Green Sand, No-Bake, or Steel Sand — with DFM feedback and indicative pricing within 24 hours.
✓ DFM feedback in 24 hours
✓ NDA available before sharing drawings
✓ ISO 9001:2015 certified
✓ 40+ years sand casting experience