An engineering buyer looking in Thailand for a moulded appliance housing, a stamped machine guard or a turned pump shaft finds many of the same factories that serve the automotive chain. The processes are the same. What differs is the approval system around them. An automotive part arrives with a ready-made framework of approval documents; a part for an appliance, a machine or a piece of equipment does not, and the buyer has to decide what proves the part is right.
This article covers that decision for non-automotive parts, and what happens when you supply materials to the Thai factory.
💬 Placing appliance or machinery parts in Thailand, or adding a Thai second source? For each project we find, vet and manage the factory that fits the part. See our sourcing agent service for Thailand or send us the drawing and annual volume.
How is a non-automotive part approved, if not by PPAP?
By an approval package you define yourself, built backwards from whatever your own customer or certifier will check on the finished product.
Our note on auto parts contract manufacturing in Thailand covers the automotive route, where the customer chooses a PPAP submission level. Outside automotive there is no shared framework. That is fine if the evidence is chosen deliberately; it becomes a problem when your own customer asks for a document the factory was never told to keep.
| Appliance and electrical product parts | Machinery and equipment parts | |
|---|---|---|
| What decides acceptance | The safety certification of the finished product, plus appearance | Fit, function, wear and strength in the assembled machine |
| What the part must not change | Any material or component listed in the product’s safety test report | Material grade, heat treatment, critical dimensions |
| Typical evidence per lot | Material declaration matching the listed grade, appearance check against limit samples | Dimensional report on critical characteristics, material and hardness records |
| Where the risk usually sits | A resin or insulating material substituted for one of the same family | An unstated hardness, a fit tolerance read from the wrong standard |
Write the column that applies into the request for quotation, so the factory knows which of its quality routines to apply.
Where do you find the right Thai shop for the process?
Search by process — injection moulding, stamping, machining, die casting, fabrication — and use the Board of Investment’s subcontracting service and the SUBCON Thailand fair as shortlisting tools alongside the registry check.
A “metal parts maker” may stamp, machine or fabricate, and only one of those makes your part. Ask which processes run in-house; plating, painting and heat treatment are often subcontracted, which is normal if the subcontractor is named.
Two Thai public routes are built for exactly this kind of search:
- The BOI’s Industrial Linkage Development Division, originally set up as the BOI Unit for Industrial Linkage Development (BUILD), runs a subcontractor database and a sourcing service. Foreign buyers can send an enquiry, receive supplier information to screen, and ask for meetings.
- SUBCON Thailand, the subcontracting fair and business-matching event co-organised by the BOI and the Thai Subcontracting Promotion Association, brings parts makers together with buyers in Bangkok.
Neither route vets a factory for you. The checks that follow — the Department of Business Development registry, the certificate check, the visit — are set out in finding and checking factories across ASEAN and Taiwan and in our buyer’s guide to sourcing from Thailand.
Checked against the BOI’s BUILD brochure and the build.boi.go.th site on 19 October 2026.
Appliance parts: the safety file fixes the material
If your finished product holds a safety certification, the materials and components named in its test report are part of the specification, and the Thai factory must use exactly those, not an equivalent.
Safety test reports for electrical products, including reports under the IECEE CB Scheme, commonly list the components and materials that matter for safety — insulating plastics, internal wiring, switches, inlets — by maker and type, and changes to that list are recorded as report revisions. A housing in a resin “of the same family”, or a terminal block from another maker, may be a good part and still fall outside your product’s certification.
Three lines in the purchase order prevent this:
- Name the listed material exactly. Give the resin maker’s grade designation, colour code and the flame rating the report relies on, and state that no substitute is allowed without your written approval. The general resin-grade discipline is in injection moulding in Vietnam; it applies unchanged in Thailand.
- Require evidence per lot. A material lot number on the moulding record, traceable to the resin delivery, lets you prove which grade went into which parts if the certifier asks.
- Cover bought-in components. If the Thai factory also assembles cable sets, switches or terminals into the part, the same rule applies to each listed component. A wire harness is often where an unapproved substitution enters an appliance; see wire harness manufacturing in Vietnam for how to control it.
A metal chassis that forms part of the earthing path needs bare contact points, so the drawing should show where coating is masked. Restricted-substance declarations for the EU and similar markets are handled as described in quality documents from a parts supplier.
💬 Need the listed materials and components in your safety report carried into a Thai purchase order without gaps? Send us the part drawing and the relevant page of the report.
Machinery and equipment parts: function decides
For a machine part, acceptance rests on fits, hardness, material and the dimensions that matter in assembly, so those characteristics must be marked and measured, not left to the general tolerance.
A shaft, a guide block or a welded frame is judged by whether it fits and lasts. The risk is that the factory cannot tell which dimensions matter most. Mark the critical characteristics, ask for a measured report on those for the first lot and a sampling plan after that, and state the heat-treatment condition together with a hardness range and the place it is measured. How to write tolerances, fits and the general tolerance note so they survive translation is covered in CNC machining drawings and tolerances; forged blanks are covered in forgings from Vietnam, and the same specification points apply to a Thai forge.
Two habits matter more for machinery than for appliances:
- Spare-part traceability. A machine part may be reordered years later, one at a time. Keep the approved revision, material and process route on file, and have the part number and revision marked on the part.
- Standard parts by standard. Fasteners, springs, pins and bearings fitted by the Thai factory should be specified by their standard and property class, not by appearance. The sourcing points for those items are in fasteners and springs from Vietnam.
Thai shops may work in JIS, ASTM, EN or Thai Industrial Standard designations. Ask which the shop uses by default, and accept any grade from another system in writing.
Supplying materials or components to a Thai factory
If you consign resin, steel, components or tooling to the factory, the factory’s customs status — BOI promotion, a Section 29 duty refund, a bonded warehouse or a free zone — decides how those goods enter, how they are recorded and what may happen to the surplus.
Buyers consign materials for good reasons: a listed resin, a component the factory cannot buy, a price agreed at group level. In Thailand, imported materials used to make goods for export can be relieved of duty through several routes, each with its own records:
| Factory’s status | What it means for consigned goods | What to ask the factory |
|---|---|---|
| BOI-promoted, with the Section 36(1) benefit | Import duty on raw or essential materials used to produce goods for export can be exempted for the promoted activity; the BOI controls imported stock and production formulas | Is the promotion current, and does it cover this product? How will our materials be recorded? |
| Duty refund under Section 29 of the Customs Act B.E. 2560 | Duty is paid on import and refunded when the finished goods are exported within the period the law sets | Who pays the duty up front, and who receives the refund? |
| Bonded warehouse or free zone operator | Goods are held and processed under customs control; removing them into the Thai market triggers duty | Can our surplus material and rejected parts be exported back, or must they be destroyed or duty-paid? |
| None of the above | Duty and VAT are paid on import in the normal way | Who is the importer of record for our materials? |
So agree three things in writing: who is the importer of record for anything you send; what happens to surplus material, rejects and scrap, which under these regimes cannot simply be sold locally (BOI guidance, for example, provides for surplus to be exported, duty-paid or destroyed with approval); and who owns the consigned material at each stage.
These regimes have detailed procedures that change by announcement. Confirm the current conditions with the BOI or the Thai Customs Department before you build a cost case on them. Checked against BOI guidance on Section 36 of the Investment Promotion Act and Thai government guidance on Section 29 of the Customs Act on 19 October 2026.
Moulds and dies follow the same logic when they are brought into Thailand rather than made there. Ownership, marking and recovery belong in the contract; see mould and tooling ownership.
Shipping the parts out
Check three things before the first shipment: whether any export control applies, which trade agreement and proof of origin your destination will accept, and whether a Thai compulsory standard is relevant at all.
- Export control. Most metal and plastic parts are untouched by Thailand’s controls on weapons-of-mass-destruction-related items, but some machine and electronic parts can be. How to ask the factory for a written classification is in contract manufacturing in Thailand, Taiwan or Malaysia.
- Origin. A Thai part assembled from imported components may or may not qualify under a given agreement. For Japan, see EPA or RCEP for ASEAN imports into Japan; for a factory in Vietnam receiving Thai parts, see proof of origin for ASEAN and Taiwan imports into Vietnam.
- TISI. Thai compulsory standards govern products made or sold in Thailand. A component made for export is usually outside them, and the export provision for products that are inside them is explained in the auto parts note linked above.
To compare a Thai quotation with one from Vietnam or elsewhere on the same basis, use comparing Asian quotations on landed cost.
The enquiry pack for a non-automotive part
Send every Thai candidate the same pack, so the quotations differ only in what the factories would actually do.
| Item | Appliance part | Machinery part |
|---|---|---|
| Drawing and model | Revision on every sheet; which governs | Revision on every sheet; critical characteristics marked |
| Material | Exact listed grade, colour and flame rating; no substitution | Grade with its standard number; accepted equivalents |
| Process route | Moulding or stamping in-house; named subcontractors | Machining, heat treatment, finishing; named subcontractors |
| Evidence per lot | Material lot traceability; appearance against limit samples | Dimensional report on critical characteristics; hardness record |
| Consigned items | Listed resin or components; importer of record; surplus rule | Bar stock, castings or forgings; importer of record; surplus rule |
| Packing | Scratch protection for visible faces | Rust prevention for machined faces |
| Volumes | First order and annual forecast | First order, forecast and spare-part demand |
Approval of the first samples, and what to freeze at each stage, is covered in sample approval stages; the same staging works for a Thai part.
💬 Want one enquiry pack sent to several Thai factories in parallel and the answers set side by side? That is how we run sourcing from across Asia. Start with the drawing.
Frequently asked questions
1. Do non-automotive parts from Thailand need PPAP?
No framework requires it. Ask for a PPAP-style package if your customer expects one; otherwise a first-article report, material evidence and an agreed inspection plan are usually enough. Decide before the first sample.
2. Can a Thai moulder use an equivalent resin for an appliance housing?
Only with your written approval, and only after you have checked whether the resin is listed in your product’s safety test report. A substitute listed nowhere in the report may require the report to be revised before the parts can be used.
3. How do I find Thai suppliers for a specific process?
Search by process, then use the BOI’s Industrial Linkage Development Division (BUILD) sourcing service and the SUBCON Thailand fair alongside trade directories. Check every candidate in the Department of Business Development registry and visit before ordering.
4. Can I send my own materials to a Thai factory?
Yes. Agree who imports them, how the factory’s customs status treats them, who owns them during production, and what happens to surplus and scrap. Under the BOI, duty refund, bonded warehouse and free zone regimes, surplus usually cannot be sold locally without paying duty.
5. Does my part need a TISI mark if it is made in Thailand for export?
Usually not. TISI’s compulsory standards apply to listed products made or sold in Thailand, and the law has a separate provision for listed products made to a foreign standard for export. Check the current list for your product.
Sources: Thailand Board of Investment, BUILD brochure and build.boi.go.th (Industrial Linkage Development Division, SUBCON Thailand); BOI guidance and announcements on Section 36(1) of the Investment Promotion Act B.E. 2520 (including Announcement Por 3/2556); Thai government guidance on duty refund under Section 29 of the Customs Act B.E. 2560, bonded warehouses and free zones; IECEE CB Scheme test certificates and critical component lists. Checked on 19 October 2026 — confirm the current text before you rely on it.
More industrial sourcing guides: Plastic Extrusion in Vietnam: Dies, Dimensions and Regrind · Rubber Moulded Parts From Vietnam: Seals, O-Rings and Mounts · Castings and Forgings From India: Clusters, Specs, Shipping. All guides by category are on the industrial sourcing page.