Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D3647-16 – Standard Test Method Technical Guide
📐 Overview and Scope of D3647-16
ASTM D3647-16 is a standard practice issued under the fixed designation D3647, providing a systematic method for classifying the composition of reinforced plastic pultruded shapes. Developed by ASTM Committee D20 on Plastics and Subcommittee D20.18 on Reinforced Thermosetting Plastics, its principal objective is to offer a clear codification means and descriptive limits for classification. This standard addresses the critical compositional elements of pultruded profiles without specifying performance characteristics, making it an essential tool for material specification and communication within the industry.
Note: This practice has no known ISO equivalent, underscoring its specific role in the North American and international standardization of pultrusion compositions.
🧬 The Four-Letter Composition Code
The classification method in ASTM D3647-16 is founded on a concise four-letter code. Each sequential position in the code has a particular significance, describing a distinct aspect of the pultruded shape’s composition. The general structure of this code is as follows:
| 🔤 Code Position | 🎯 Composition Aspect | 🟦 Applicable Codes | 📝 Description |
|---|---|---|---|
| 1st | Reinforcement Material | G, C, O, S | Glass, Carbon, Other, Special (must be ≥90% of total reinforcement) |
| 2nd | Reinforcement Type | R, M, C, W, S | Roving, Mat, Combination, Woven, Stitched (must be ≥90% unless C) |
| 3rd | Resin Type | P, E, V, F, U, O | Polyester, Epoxy, Vinylester, Phenolic, Urethane, Other |
| 4th | Filler Amount | U, F | Under 5% of resin weight / 5% or more of resin weight |
Resin Type Designations (3rd Position)
The standard provides specific codes for the resin matrix, which is a critical component of the pultruded composite:
| 🔤 Code | 🧪 Resin Type |
|---|---|
| P | Polyester |
| E | Epoxy |
| V | Vinylester |
| F | Phenolic |
| U | Urethane / Urethane Hybrid |