Small-part finishing for factories in WHA Eastern Seaboard
WHA Eastern Seaboard sits inland in the Pluak Daeng area of Rayong, on Highway 331 — far enough from both ports that we will not tell you which one is closer.
We run one plant, and it is in Samut Sakhon. This page covers collection and delivery for customers in Rayong — it is not a branch or a facility in Rayong.
This estate at a glance
| Province | Rayong |
|---|---|
| Road corridor | Highway 331 — Eastern Seaboard |
| Nearest sea port | — |
| IEAT-designated | Yes |
| Eastern Economic Corridor | Yes |
| Industry mix | automotive & parts, steel & metalworking, machinery |
IEAT-designated covers both estates operated by the Industrial Estate Authority of Thailand and joint-operation estates run with a private developer. A dash means we could not confirm a single status for the whole area — some of these names describe a factory district rather than one designated estate.
A dash in the port row means the estate sits inland between two ports and we will not guess which is nearer. Nothing on this page is a distance, a drive time or a delivery-time promise.
Reviewed:
What this estate is
WHA Eastern Seaboard, still widely called Hemaraj, is an IEAT joint-operation estate on the Highway 331 inland corridor inside the Eastern Economic Corridor. Its industry mix is automotive, metalworking and machinery, and it is one of the deep-inland EEC clusters: it does not sit on the coast, which is exactly why the port row on this page is empty. Laem Chabang and Map Ta Phut are both plausible gateways from here, they serve completely different cargo, and we would rather leave the field blank than publish a distance we cannot verify.
What this estate asks of a small part
The automotive and machinery mix here produces the widest hardness range on this list. Machinery parts are specified for wear and are often tested at a surface, while automotive fasteners are specified as a delivered property class and tested through the section — the same furnace, two entirely different acceptance rules. Add Cr3+ zinc for the corrosion requirement and the ISO 4042 baking rule follows the hardness, not the part name. We ask for the acceptance rule at quotation because it decides which test result actually settles the lot.
Services for factories in this estate
Hardening, Cr3+ zinc plating, phosphate coating and in-house lab testing, all on small parts at bulk volume.
The estate takes Highway 331, the inland Eastern Seaboard corridor, and freight from here can go either to the container terminals at Laem Chabang or to Map Ta Phut, which mainly handles petrochemical and bulk cargo rather than containerised parts. Since we cannot ground which port is nearer to the estate, we leave the row blank rather than guess. Parts reach our Samut Sakhon plant by motorway and outer ring, arranged per lot with sales.
Questions we get from this estate
Why is the port field empty for this estate?+
Because we could not ground it. Pluak Daeng sits inland between the Laem Chabang container port and the Map Ta Phut industrial port, and publishing a guess in a table that looks authoritative would be worse than a dash. Everything else on this page — corridor, IEAT status, industry mix — is checkable.
Our drawing gives surface hardness, our customer audits core hardness. Which do you work to?+
Both, once the drawing says which is which. Surface and core are different acceptance rules and a case-hardened part passes one while failing the other by design. Mark on the drawing where the hardness is measured and what the tolerance band is, and the test record will report it at that location.