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 Are there quantity price breaks on stock items?
What is the difference between Steel, Chrome, and Carbide?
What is the difference between Adjustable Thread Rings and Solid Thread Rings?
What is A2LA?
What are "Part Type Masters"?
What is API?
What is Helical Coil?
How can I lengthen the life of my gage?
What is uncertainty?
Common Misconceptions About Certification Requirements
What’s the difference in Steel, Chrome, and Carbide?
Gages
are manufactured from Tool Steel and hardened to 58 - 62 Rc, unless
specified otherwise by the customer. Chrome is a plating process that
increases the hardness/wearablity and protects the gage from corrosion.
Carbide is a sintered metal with a harder wear surface than Steel and
Chrome with a comparable hardness of 79 - 81 Rc, but it is also brittle.
What is the difference between Adjustable Thread Rings and Solid Thread Rings?
Adjustable
Thread Rings are as the name implies, adjustable. As the ring gage is
used it will wear outside the allowable tolerance but can be
re-adjusted back into tolerance increasing its wear life. In the US,
Solid Thread Rings are usually master rings used for setting Internal
Thread Comparators. Outside the US, the standard design of working
gages is a solid ring. The Adjustable Thread Ring is an American design.
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What is A2LA?
A2LA
is The American Association for Laboratory Accreditation. This
accreditation means an independent qualified party audited and appraised
GSG’s lab to ISO 17025. A2LA is recognized throughout the world as a
registrar for laboratories. Glastonbury Southern Gage is one of very few gage manufacturers
that has this level of accreditation for our laboratories.
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What are “Part Type Masters”?
Part
Type Masters are used to set up gaging systems typically in a
manufacturing line. Due to GSG’s unique capability to manufacture part
masters with very close, gage-like tolerances, we have developed this
market to serve gage system manufacturers. Typical masters including
brake drums, rotors, connecting rods, crank shafts, pistons of all
sizes, etc., are furnished to the auto industry, but many other
industries can improve their processes by using part masters.
What is API?
API is the American Petroleum Institute.
Typical specification include:
- Spec 5B - Casing, Tubing & Line Pipe Threads
- Spec 7 - Rotary Drill Stem Elements
- Spec 11B - Sucker Rod
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How can I lengthen the life of my gage?
A
longer gage life can be obtained by making sure the gages are handled
and stored properly. Gages should be handled like any precision tool or
measuring device that is required to inspect close tolerances.
Mishandling and poor storage can cause nicks or other deformities which
will destroy the gage. When storing gages make sure the gage surfaces
are protected and lubricated to prevent corrosion.
Many people talk
about uncertainty, what does that mean? When we discuss uncertainty, we
in the dimensional measuring field, are talking about the influences
that affect the measurement being made. Some of the affects are the
environment, equipment, methods, personnel, instrument used, procedure,
etc.
Some examples are:
The room in which the measurement is being performed:
We say that the
temperature is 68 degrees plus or minus 1 degree, however the
temperature at the measuring surface could be at 67 or 69 degrees. That
difference could make a large difference in the true measured size. For
example steel moves at 6.3 millionths per degree per inch size
difference (co efficiency of expansion) in steel. A steel disc 1.000”
class XX (+/-.000015”) diameter could measure .999994” or 1.000006”
respectfully. Half of the tolerance is lost by only considering
uncertainty in temperature. Imagine the measurement not taken in a
controlled environment!
Equipment:
You could measure
the same disc using any instrument you choose. A highly accurate
measuring instrument measuring in millionths of an inch would typically
produce a lower uncertainty than a vernier caliper measuring in
thousandths of an inch. No one can tell the customer what instrument
they will use, however the uncertainty measuring with a vernier caliper
would be quite large and well outside the tolerance of the 1.000” disc.
For example the uncertainty using the highly accurate measuring
instrument measuring in millionths of an inch might be .000005” and the
vernier caliper might be .003” inches. Neither method is wrong; however
ignoring the uncertainty may mean the measurement is unusable.
Misconceptions about Certification Requirements
There
are several common misconceptions of what is required on a calibration
certificate for Inspection, Measurement, and Test Equipment (IM&TE)
according to ISO-17025, or ANSI/NCSL Z540-1. The requirements for a
calibration certificate are listed in the previously mentioned
standards in a section specific and only for calibration certificates.
Misconceptions arise because the sections in the standards that apply
to the 'Quality System' supporting the IM&TE are incorrectly
applied to the calibration certificate.
Some
calibration labs and companies have designed their calibration
certificate to supply anything and everything their customers might
want whether listed in the properly applied section of the standards or
listed in other and improperly applied sections of the standards. This
eliminates the questions that arise from their customers, and may be
some of the source if not fuel for the misconceptions. Glastonbury
Southern Gage takes a very active role in many ANSI standards writing
committees, and organizations like AMTMA, and we believe the standards
should be applied properly as written because they were conceived,
written and published to create consistency in industry.
GSG
provides a table of comparisons of the two standards for calibration
certificates, included is a column for ISO 10012-1, which is for the
'Quality (Calibration) System' supporting the IM&TE, not the
certificate. These comparisons are available on our web site or our
technical CD.
The most common
misconception is that the certificate must include the instrument used
to obtain the calibration results, and its calibration information.
However, it is not an item in the requirements lists for a certificate.
This misconception appears to result from the requirement that a
certificate has a ‘Traceability Statement,’ and the Quality System have
‘the source of the calibration used to obtain traceability.’ To help
people understand the application of this requirement we have added a
sentence to our certifications that states "The user's calibration
source for NIST traceability is GSG."
In
conclusion, we at GSG would like to offer our services in interpreting
and applying these calibration standards. Any customer you have that is
demanding things not required by the standards, a list can be obtained
from GSG. If this doesn't solve the problem, have them get out their
copy of the standard and find the requirement they are demanding. You
will discover they are in a section other than the appropriate section
for calibration certificates. If you need assistance in helping them
understand which section they should be looking in or how to properly
apply the requirements they are looking at, we will be more than happy
to talk with them.
For
that group of customers who have designed their quality system without
adhering to the standard, and now require more than the standards do
for calibration certificates, we will be glad to furnish a calibration
certificate with any and all information the customer desires. Have
your customer list all the additional items they want on the
certificate, be sure they are clearly stated on your request for quote
so the appropriate costs can be added for this additional work. Be sure
also that this same list is prominently displayed on your purchase
order, because special handling is required to comply with these
special requests.
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