Our partners at Parker – a long-time Gallagher O-ring supplier – discuss this trend in a recent blog post.
As of last year, NARs has gone up by nearly 20 percent. In most cases, these incidents involved problems with the manway. The four main issues were loose bolts, missing gaskets, misaligned gaskets and deteriorated gaskets.
Parker went to work looking for a sealing solution that could eliminate the leading causes of NARs while also providing a gasket that could be used more than once.
The company looked for feedback from experts in the use of manway gaskets, as well as input from the AAR and the Department of Transportation.
Parker used this input to design and patent its Sure Torque gasket, which features a stainless steel insert and over-molded elastomers. It then tested Sure Torque against four other popular gaskets made by competitors.
These were the parameters for the test:
- The test centered around a heavily-used manway fitting at room temperature.
- It was secured using the start pattern over three passes to 250 pounds.
- Pressure was increased in 10 psi increments to 165 psi and monitored for 24 hours.
- The three steps were repeated until the test gasket failed.
In each case, the competitor’s gaskets leaked and showed torque loss after the first or second cycle. They also showed either cracking or compression set after the first two cycles. For each of the competitors, the leaks occurred before reaching 165 psi, and the torque loss was 10 ft-lbs or more.
The Sure Torque gaskets, on the other hand, had no leaks at 165 psi after 30 cycles, had a torque loss of less than 3 ft-lbs after 30 cycles, and showed no signs of permanent compression set.
In short, Parker found that its Sure Torque gasket and its stainless steel ring resolved the leading issues causing manway NAR. It’s also the only gasket that can be reused, only needs to be torqued once, can’t fall into the manway, is easy to install and requires minimal maintenance.
If you want to know more about finding the right seal for your machinery, contact Gallagher’s engineering department. Our experts can guide you toward sealing solutions for a number of industries.