Product and assembly brief
A plastic-direct screw forms its mating thread in a prepared plastic receiving hole rather than engaging a separate metal nut or threaded insert. Select the screw together with the actual polymer and moulded boss, not by head appearance alone. The manufacturer references below illustrate different plastic-specific thread designs; they do not establish FastenerBridge brand affiliation, licensed manufacture or availability.
Product forms and reference names
| Choice or field | What to identify |
|---|---|
| Plastic-specific direct thread forming | Specify the selected profile and receiving component together. A sheet-metal ST tapping-thread reference or DIN 7500 metal-forming designation alone does not identify a plastic-specific design. |
| EJOT PT reference family | EJOT describes PT as a plastic-specific thread forming directly in thermoplastics. Its WN 14 company-reference family includes different heads and drives; a head code is not a universal plastic joint specification. |
| EJOT DELTA PT reference family | EJOT describes DELTA PT as a development of PT with geometry adapted to material displacement. WN 54 head/drive references belong to this maker family, not a DIN/ISO equivalence claim. |
| EJOT EVO PT reference family | A separately identified EJOT plastic-direct family, with application-specific calculation and component design support. Do not treat EVO PT, DELTA PT and PT as interchangeable ordering names. |
| REMFORM II HS reference family | ARNOLD describes an asymmetric thread with a rounded crest-side tip and curved load flank, with an enlarged core for its high-performance plastic applications. Exact supplier identity, profile and application qualification must be confirmed; the name is not a generic interchangeable standard. |
| Metal insert plus machine screw alternative | An after-moulding or moulded-in metal insert provides a separate female thread. This is a different assembly route, not another head form of a plastic-direct screw. |
Thread identity is not head identity
Pan, round washer, hexagon washer and countersunk heads describe seating and drive choices, not the plastic-contacting thread. EJOT's published PT WN 14 and DELTA PT WN 54 lists associate head/drive forms with different company-reference families. Specify the complete selected code and controlled drawing. No generic catalogue image can prove the flank profile, pitch, core or mating-hole design.
Polymer, receiving hole and boss
Identify the actual resin grade, reinforcement and conditioning, together with the moulded receiving-hole and boss drawing. ARNOLD's application discussion identifies component/screw geometry, hole diameter, material condition and fibre content as joint variables. Procurement guidance here is an inference from those variables: supply the hole depth, draft, wall geometry and tolerance basis, rather than adopting a universal diameter ratio. Blind-hole clearance and usable thread engagement need selected-design review.
Assembly and service conditions
Record the assembly equipment and speed, seating condition and application environment. Temperature, load duration and dynamics can matter to a plastic joint; a manufacturer's application result is not a guarantee for a different resin or component. Request a selected-joint qualification plan for installation, stripping, screw failure and relaxation as applicable. This page gives no assembly torque, preload, retention, reuse or temperature rating.
Keep direct forming separate from other routes
Plastic-direct forming displaces the receiving material. A thread-cutting design removes material and needs separate cutting/chip evaluation; a drill point addresses another installation mechanism. A machine screw in a metal insert uses an existing metal female thread. Repeated dismantling requirements should be declared for application review, not inferred from a generic self-locking description.
Drawing and supply confirmation
Manufacturer product pages identify reference families, not stock or production capability at FastenerBridge. EJOT's detailed company drawings and calculation services may require authorized access; no registration, confidential-access request or calculation submission was made. Normative dimensions, tolerances and selected application recommendations remain gaps until controlled specifications and actual quotation are confirmed.
Specification fields
| Choice or field | What to identify |
|---|---|
| Reference identity | Manufacturer family, complete selected head/drive code and revision-controlled specification; declare whether a named proprietary product is required. |
| Polymer | Actual resin grade, reinforcement/fibre content, conditioning and relevant moulding condition; generic plastic is insufficient. |
| Receiving component | Boss and hole drawing, hole diameter/depth/draft, wall geometry, tolerance basis and blind-hole clearance for selected-design review. |
| Screw geometry | Selected thread profile/pitch/core, lead form, length definition and usable engagement, confirmed by controlled drawing rather than photograph. |
| Head and drive | Head bearing surface or countersink seat, access and exact drive/bit interface; no generic tool compatibility assumption. |
| Material and finish | Specified screw material, treatment and finish, with compatibility and corrosion requirements reviewed for the actual resin/environment. |
| Assembly requirements | Equipment, speed and seating, validation method and any required dismantling cycles; approved torque/window from selected joint only. |
| Service and purchase | Load/environment/duration requirements, inspection evidence, quantity and packing; actual qualification, stock and delivery remain quotation facts. |
Common product questions
Can a normal sheet-metal tapping screw be substituted?
Not on head similarity alone. Plastic-specific geometry and the actual resin, hole and boss require review. An ST or metal-forming reference is not evidence of equivalent plastic-joint performance.
Are PT, DELTA PT, EVO PT and REMFORM the same standard?
No equivalence is asserted. They are manufacturer reference families, with different identified geometry and selection systems. Obtain the required complete specification and permission or authorized supply basis where applicable.
What pilot-hole diameter and tightening torque should be used?
There is no universal value on this page. Both depend on the selected screw, polymer, receiving component and assembly conditions. Controlled recommendations and joint testing remain required.
Does the image show a branded screw or tested assembly?
No. It is an AI-generated generic appearance reference. It cannot establish a proprietary profile, normative dimensions, delivered model or tested plastic-joint performance.
Related product choices
- Self-tapping screw parent and head choices
- Thread-forming screws for metal
- Machine screws for an existing female thread
- After-moulding plastic inserts
- In-moulding plastic inserts
Product references
References checked 10 October 2026 identify structures, not FastenerBridge stock, compliance or brand affiliation. Final requirements follow the selected specification. No normative dimension, load rating or tightening torque is stated.