Injection Molded Plastic Obturator for 105-mm M735 Projectile
Abstract
The objective of the contract was the development of a nonproprietary, low cost, production process for nylon obturators for the 105-mm M735 projectile that would give product performance equivalent to that obtained from current production machined from centrifugally cast nylon 6/6. Injection molding, using general purpose molding grade nylon 6/6 (DuPont Zytel 101L), was selected as the preferred process, based on cost analysis comparisons with compression and transfer molding. A single cavity, diaphragm-gate mold was designed and built. Molding cycles and post molding treatments were developed to minimize molded-in stress levels and to meet dimensional requirements after installation. Injection molded obturators met all the physical property requirements specified except for the water absorption value of 0.58 average vs maximum of 0.42. Installation on M735 projectiles was demonstrated successfully at ARRADCOM using modified standard procedures. Ballistic firing trials at -53 F, +70 F, and +145 F showed almost 1 to 1 correlation with control cast obturators.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1983
- Accession Number
- ADA126106
Entities
People
- Martin Connor
- Stephen B. King