Know the intricacies of choosing metric thread gauges
A person new to the world of tapping and threading might be flabbergasted by the myriad of gauging equipment that lay in front of him. In order to understand the world of metrology, one needs to grasp the concept of metric thread gauges and its intricacies. So, no need to panic as yet. This article provides a deeper insight into the types of gauges and their areas of application.
1. ACME thread gauges:
ACMEs find primary application in thin wall areas. They are durable and strong in nature. In areas of the coarse pitch, ACME thread gauges find significant use quite similar to those used in oil field equipment.
2. UN thread gages:
Invariable or uniform thread series having a consistent bore per inch are measured using UN gauges. The primary function of gauges is to attain impeccable accuracy, and the UN series justifies this cause. This lineup has eight distinct varieties starting from the 4TPI and extending up to the 32 TPI mark. When this fixed UN series receives complementation from C, F, or EF segments, it gives rise to the following variants:
UNF – Unified National Fine Series UNC – Unifies National Coarse Series UNS – Unified National Special UNEF thread gauges – Unifies National Extra Fine Series
3. Trapezoidal Thread gauges:
Trapezoidal gauges find major application in heavy machinery industries. They are mainly used for translational motion. These gauges aim to provide accurate measurements of taps as well as any damage due to overuse.
How to choose your thread gauge?
Now, since you have received some knowledge on the types of thread gauges, it is important to take a look at the specifics of choosing a thread gauge.
The trivial condition of buying a gauge is to perform a close check of a nation’s threading standards. For example, US specifies its thread gauge standard as ASME/ANSI B1.2 for UN screw threads while ANSI B1.16 M for metric thread gauges. Also, reference temperature should remain consistent around the 68 F mark so as to ensure the accuracy of inspection.
So, one should keep in mind the following points before opting for any type of screw gauges.
The gauge should support special and standard tolerance levels.
Complete inspection certificates should be available on demand.
The minimum strength of a gauge should exceed the standard limits by a considerable amount.
UNEF thread gauges of the UN thread gauge and similar others must provide true dimensions.
Double surface gauges are necessary so as to allow ample space for markings when necessary.
Greater resistibility against wear and tear.
ISO 9001 certification should be available on all gauges.
One should keep in mind that a thread head is prone to wear and tear with overuse. This may hamper accurate measurements leading to a quality loss. So, one must check a gauge for any wear and tear or zero error so as to prevent any unprecedented damage.
So, keeping a clear knowledge of threads and gauges is essential in order to garner accurate measurements. Metric thread gauges should pass the above points to ensure safety and security of machines at work.