DEVELOPMENT OF DAMPING TREATMENTS FOR NEW CONSTRUCTION SUBMARINES
Abstract
The development of elastomeric materials to replace chromated felt in constrained-layer treatments for damping heavy plating in new construction submarines was undertaken. A treatment having a weight ratio to the treated plate of 1 to 4 and utilizing a perforated nitrile rubber damping layer was found to be almost as effective as Treatment 198, a similar treatment developed by the Rubber Laboratory which utilized chromated felt. The new treatment, designated Treatment 227, consisted of an Al constraining layer 1-1/4 in. thick and a perforated nitrile rubber damping layer 1/16 in. thick. It was fastened by means of 1/2 in. studs on 12 in. centers to 1-3/4 in. thick steel plate. The average damping at 75 F for Treatment 227 over the frequency range of 50 to 2000 cps was 6.2% of critical as compared to 6.5% of critical for Treatment 198. It was found that the damping behavior of the nitrile rubber layer was affected similarly to the chromated felt by temperature change. Maximum damping occurred at 65 F. Substantially lower damping were obtained at 35 and 120 F. Work was continued on the development of damping treatments which will be efficient over the temperature range of 35 to 120 F.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1962
- Accession Number
- AD0281835
Entities
People
- J. Oser