Precision gauging for aerospace & defence.
Aerospace and defence components carry tight thread and fit tolerances, where a gauge's acceptance call has to be unambiguous, since a failed thread fit in this industry has real consequences. Inspection here leans on tightly controlled thread classes and gauges that are independently certified, not just accurate in principle.
Dry-seal and taper threads
Where a port or fitting has to seal by the thread itself, ANPT gauges to SAE AS71051B check the controlled truncation that a dry-seal thread depends on, using L1 and L2 plug and ring members plus a 6-step crest-crack check. NPTF gauges to ANSI/ASME B1.20.5 cover the equivalent commercial dry-seal thread, with L1 and L3 members.
Unified and special threads
Fastener threads on aerospace hardware are frequently unified, UNC, UNF or UN, to ANSI/ASME B1.2, checked with thread plug and ring gauges. Where a standard family does not cover an unusual length, pilot or depth-step requirement, we build special gauges to drawing.
Why traceability matters here
Every thread gauge we supply ships with a test certificate accredited by NABL to ISO/IEC 17025, giving a recorded, traceable basis for the acceptance decision. Choosing the right gauge starts with confirming whether the drawing calls for a standard NPT/NPTF thread or the dry-seal ANPT variant, since the two are not interchangeable, followed by confirming the unified class where fasteners are involved.
Gauge families used for this inspection
Questions about aerospace & defence
Which gauge families are typically used in aerospace and defence inspection?
ANPT and NPTF dry-seal taper gauges, plus unified thread plug and ring gauges for fastener threads.
Which standards apply?
ANPT to SAE AS71051B, NPTF to ANSI/ASME B1.20.5, and unified threads to ANSI/ASME B1.2.
What is the difference between NPTF and ANPT?
Both are dry-seal taper threads checked without a separate sealant; ANPT to SAE AS71051B and NPTF to ANSI/ASME B1.20.5 use the same L1/L2/L3 member system with standard-specific acceptance limits.
Does every gauge come with a traceable certificate?
Yes. Every gauge we supply is accompanied by a test certificate accredited by NABL to ISO/IEC 17025.
Can you make special or non-standard gauges for aerospace parts?
Yes, we build non-standard and special gauges to drawing: extra lengths, air grooves, pilots and depth steps.
How do I request a quote?
Share the thread size, standard or a drawing on our quote page and we will confirm the class, availability and pricing within one business day.
Tell us what you are inspecting.
Share your thread, standard or drawing and get the right acceptance class, certified.