Unmatched Durability
The difference is simple… There is only one moving part.
Perma-Cal® Direct Drive
Competitors C-Tube Design
One moving part
No Gears, No Linkages, No Springs
Helical Bourdon Tube attached directly to the pointer shaft
Multiple moving parts
Over time, movement-amplifying gears, linkages and springs can wear or break
Requires lubrication for proper functionality
No liquid fill
Internally dampened to reduce pointer flutter
No internal mechanical components requiring lubrication
Liquid filled
Liquid filled to reduce pointer flutter and for internal lubrication
Over time, liquid fill can leak or cause discoloration resulting in premature failure
Greater life equals lower costs
Fatigue life oftentimes of 1,000,000 cycles or more
Reduces maintenance costs and allows for extended recertification cycles
Shorter fatigue life
Fatigue life often only 20,000-30,000 cycles
Internal wear results in increased maintenance and shorter recertification cycles
Safety is prioritized
All gauges feature a Solid Front Case for greater protection
Low volume minimizes spillage if catastrophic failure occurs
Safety is optional
Optional solid front case increases risk of blowout in the front
High volume spills large amounts of process if catastrophic failure occurs
Proof Pressure above industry standard
Withstands over-pressure of 150% F.S.
Standard Proof Pressure
Withstands over-pressure of 125% F.S.
Reliable temperature performance
Inconel, Helical Bourdon Tube means that accuracy is 25% less affected by changes in temperature
Options available operating from -65°F up to 600°F Media
Uncertain temperature performance
Stainless Steel, C-Type Bourdon Tubes provide less consistent readings vs. Inconel
Standard operating temperature -40°F up to 212°F Media
Consistent, accurate diaphragm seal performance
Unique, low volume design requires 85% less fill fluid. This means accuracy is 50% less affected by temperature changes
Mini-Seal compatibility provides performance advantages and significant cost savings
Inconsistent diaphragm seal performance
High Volume C-Tube combined with a larger seal requires significantly more fill fluid
Increasing temperature leads to fill fluid expansion and inconsistent accuracy
Aerospace Quality | Military Trusted
Military and Aerospace Engineers recognize the performance advantages Direct Drive Design offers and demand it on critical applications
Commercial Standard Design
C-Tube design is widely used in standard commercial and military applications, but is very rarely seen in Aerospace