 |
707.940.1506
 |
|
|
|
|
|
|
|
|
|
|
Preparation of Witness Panels
|
Witness panels are fabricated daily on the job site using materials prepared for application to the structure, and under the same conditions that are found on the job site. At the discretion of the inspector, or as outlined in the job specifications, a percentage of the panels are tested by an accredited laboratory to ensure that the materials applied on the job conform to, or exceed, the required properties and performance. The samples are typically tested in accordance with ASTM D-3039 2000, Standard Test Method for Properties of Polymer Matrix Composite Materials.
|
|
|
| Lay-Up Witness Panels for Testing |
Witness panels are required for each day materials are laminated. An accredited lab may then test these. If the witness panel does not meet the standard set for the job, the job may have to be redone or additional layers applied. It is vital that the witness panels are produced according to the following procedures. Witness panels typically consist of 3 to 4 layers for Velacarb 335u and 2 layers for Velaglass 875u.
|
| [Top] |
Remedial Measures and Repairs
|
|
FRP composites, as with all materials, can suffer damage from outside influences, and can occasionally contain defects. This document outlines most damage and defect scenarios and instructions on remedial measures.
|
| [Top] |
| Procedure for Saturator / Impregnator |
The saturator/impregnator is a manually operated machine that saturates fiber fabric such as glass, carbon, aramid etc with epoxy resins. As the fabric is pulled through a bath of epoxy resin and between two steel mandrels (that actually do the pulling) it becomes heavily saturated with epoxy. As the fabric is pulled between the mandrels the epoxy is forced deep into the fibers. The mandrels are spaced apart from each other so that the thickness of the fabric (plus a little) can pass between them. This results in a predetermined, consistent epoxy content.
The purpose of the saturator/impregnator is to increase production and to control the saturation quality on large volume installations. The saturator/impregnator can produce up to five times the saturated fabric than can be produced by hand wet-out methods. The fiber to resin ratios are much more consistent when using the saturator/impregnator. The saturator/impregnator should not be used for smaller jobs that do not have the manpower to install the fabric as quickly as the saturator/impregnator can produce it.
|
