Small-part finishing for factories in Pinthong Industrial Estate
Pinthong is a supplier estate on Highway 331 behind the port: forming, stamping and fastener plants feeding assemblers further down the corridor. Forming work brings its own finishing problems.
We run one plant, and it is in Samut Sakhon. This page covers collection and delivery for customers in Chon Buri — it is not a branch or a facility in Chon Buri.
This estate at a glance
| Province | Chon Buri |
|---|---|
| Road corridor | Highway 331 — Eastern Seaboard |
| Nearest sea port | Laem Chabang Port |
| IEAT-designated | Yes |
| Eastern Economic Corridor | Yes |
| Industry mix | automotive & parts, steel & metalworking |
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
Pinthong is an IEAT joint-operation estate in the Si Racha and Bo Win area of Chonburi, on the Highway 331 inland corridor and inside the Eastern Economic Corridor. Its mix is narrower than its neighbours — automotive parts and metalworking — and that narrowness is the point: this is an estate of formers and second-tier fastener makers rather than final assemblers, so the parts we see from it are usually mid-process rather than finished goods.
What this estate asks of a small part
Formed parts bring phosphate into the conversation for a reason most finishing pages skip. A zinc phosphate layer is a lubricant carrier for cold forming and drawing — it exists to let steel move against a die without seizing — while a manganese phosphate is an anti-galling and running-in surface for parts that slide in service. They are different processes for different problems, and asking for "phosphate" without saying which one is the most common ambiguity in an RFQ from this kind of estate. The second recurring job is quench-and-temper on cold-headed blanks to reach the class the assembler specified.
Services for factories in this estate
Hardening, Cr3+ zinc plating, phosphate coating and in-house lab testing, all on small parts at bulk volume.
Pinthong takes Highway 331, the inland Eastern Seaboard corridor, and its nearest sea port is Laem Chabang. Work moves to our Samut Sakhon plant by the motorway and the outer ring. As with every estate on this list, collection is arranged per lot with sales and we publish no transit or job-completion times — only the promise that a quote is answered within 24 hours.
Questions we get from this estate
We just wrote "phosphate coating" on the RFQ. What do you need to know?+
Which phosphate, and what it is for. Zinc phosphate is normally a pre-treatment and a lubricant carrier for forming or painting; manganese phosphate is a heavier, darker anti-galling surface for parts that slide under load. The coating weight and the follow-on oil or wax also change with the job. Tell us the function and we will tell you the process.
Can you harden cold-headed blanks to a specified property class?+
Yes — that is one of the most common jobs from this estate. Quench-and-temper to an ISO 898-1 class is a delivered-property requirement, so it is tested rather than assumed, and the achievable class depends on the steel and the diameter as much as on the furnace. Send the drawing with the steel grade and the diameter and we will tell you whether the class is reachable in that material.