50% VS 100% Bolting: What's the Difference?
When installing bolt-on flange protectors, you'll often hear the terms 50% bolting and 100% bolting. These terms describe how many of the available bolt holes are used to secure the protector to the flange.
Understanding the difference between the two methods helps ensure the protector performs as intended while balancing installation time with the level of protection required.
What Is 100% Bolting?
100% bolting means every available bolt hole is used to secure the flange protector. For Precision Piping Products' bolt-on protectors, this is achieved by installing a multiNUTS™ and machine screw in each bolt hole around the flange.
Using every bolt hole provides the highest level of mechanical stability and helps keep the protector securely in place during handling, transportation, storage, and extended outdoor exposure. Because the protector is evenly secured around its entire circumference, it is better able to resist movement caused by vibration, impact, or environmental conditions.
For applications involving long-term preservation—typically 24 months or longer—100% bolting is the recommended installation method.
What Is 50% Bolting?
50% bolting means only half of the available bolt holes are used to secure the protector. To maintain even clamping force, the multiNUTS™ and machine screws should always be installed in an alternating pattern around the flange.
Alternating the fasteners distributes the holding force more evenly and helps prevent the protector from shifting or becoming loose.
This installation method can significantly reduce installation time, particularly on large-diameter flanges with a high number of bolt holes. While 50% bolting provides a secure attachment for many short-term applications, it does not offer the same level of mechanical retention as 100% bolting and is generally not recommended for long-term preservation.
When Should You Use 50% or 100% Bolting?
The appropriate installation method depends on the application and the level of protection required.
As a general guideline:
- 100% bolting is recommended for long-term storage, extended outdoor exposure, transportation, and applications where maximum mechanical protection is required.
- 50% bolting may be suitable for temporary protection during fabrication, short-term storage, maintenance activities, or situations where reducing installation time is a priority.
Project specifications and customer requirements should always be followed when determining the appropriate installation method.
P3 Products That Use 50% or 100% Bolting
The concepts of 50% and 100% bolting apply to Precision Piping Products' bolt-on protectors that are secured using multiNUTS™ and machine screws.
These products include:
Each product is designed to provide mechanical protection for critical sealing surfaces or equipment during storage, transportation, fabrication, and maintenance.
While many applications can successfully use 50% bolting for temporary protection, 100% bolting is recommended whenever maximum retention, stability, and long-term preservation are required. Using every available bolt hole helps ensure the protector remains securely attached throughout the project's duration, providing the highest level of protection for valuable assets.
