Hex Head Steel Cap Screws, SXS Series
Hex Head Steel Cap Screws, SXS Series
Strainsert fasteners utilize an exclusive internal gaging method (U.S. Patent #2,873,341) to indicate bolt tension due to preload with strain gage accuracy. Fasteners provide a means for accurate, independent inspection of an assembled bolt for preload, thereby enhancing the structural integrity and reliability of both the bolt and the assembly.
See our force sensing bolts and studs product information page for general specifications and detailed information.
Features
The gaging process consists of the installation of foil type bonded strain gages in a small hole drilled along the longitudinal neutral axis of the bolt. This method compares favorably in accuracy and stability with the best external gage installations, but is vastly superior to external gage installations in mechanical and environmental ruggedness and miniaturization since the internal strain gage installation is self-protecting.
In most bolts, neither the gage or the drilled hole reduce the allowable bolt load in a Strainsert fastener. The hole depth is confined to the shank of the bolt, and the hole diameter is controlled so that the bolt cross-section through the threads is smaller than the section through the shank with the gage hole. Therefore, the gage installation will withstand and accurately indicate high strength loads.
Some Features Include:
- To measure accurate preload, service load and overload of bolted assemblies
- For maximum uniformity, efficiency and reliability in bolted assemblies
- For effective research, testing and manufacturing of bolted assemblies
Applications
These Force Sensing Bolts are available from ¼” diameter up to 1 ½” diameter, and are available in many different lengths. They are typically grade 9, (180 KSI) high strength alloy steel and they are intended for use in applications where hex head bolts are used.
| Specifications | |
|---|---|
| Material | Steel Alloy (SAE Grade 9), SAE 4140 or equivalent |
| Hardness | Rockwell C38 to C42 |
| Ultimate Tensile Strength | 180,000 psi Minimum; (SAE Grade 9) |
| Threads | Class 2A, rolled |
| Thread Length | 2-diameters + 1/4 inch full threads + 3/16 inch maximum imperfect threads |
| Finish | Zinc Dichromate plated. Corrosion Protection per Federal Spec. QQ P-416 Type II, Class 3 |
| Calibration | Load & Unload Calibration Load Only Calibration (Standard) |
| Performance Specifications | |
|---|---|
| Gages Type | Metal Foil |
| Gage Factor (Nominal) | 2 |
| Non-Linearity | ±1% of Allowable Load FS |
| Non-Repetition | ±0.1% FS |
| Excitation | 350-ohm (Standard) FB: 12V (Maximum) 350-ohm (Standard) QB: 6V (Maximum) 120-ohm FB: 3V (Maximum) |
| Output Signal (Nominal) | FB:3.5 to 4mV/V QB:1.3 to 1.5mV/V |
| Configuration | Full Bridge Strain Gage Circuit (Standard) Quarter Bridge Strain Gage Circuit |
| Bridge Resistance (Nominal) | 120 Ω 350 Ω (Standard) |
| Service Temperature | 150°F (Standard) 300°F (Max.) |