ISO-80369 CONICAL RING GAGE FOR MALE MEDICAL CONNECTORS
ISO 80369-7:2016 cancels and replaces the first edition ISO 594-1:1986 and the second edition of ISO 594-2:1998, clauses, subclauses, tables, figures, and annexes of which have been consolidated and technically revised. The new ISO 80369-7 specification does not define any gauges.
ISO 80369 Specifications Only Define Reference Connectors.
The authors of the ISO 80369 specification series thought that direct measurement and functional testing was the best ways to establish when a product meets the operational criteria of the specification. We agree that direct measurement and functional testing are excellent methods of validating compliance to the ISO 80369 specifications; however, we also know that these methods are is time-consuming and expensive. Because of the effort required for direct measurement and functional testing; these methods are usually only conducted for: New product approval; New tooling validation; Repaired tooling validation; and Periodic/annual validation of tooling.
So Do I Still Need Conical Ring and Conical Plug Gages?
While the authors of ISO 594/1 included Ring and Plug Gages in the specification; the authors of the ISO 80369 specification series decided to not include the physical testing conical gauges. This does not mean that the tapered plug and ring gages have no usefulness. Appropriate uses for the conical ring and plug gauges still exist and include: incoming material inspection and in-process production control. The ISO 80369 specified functional tests are not useful for monitoring fitting acceptance during manufacturing or spot-checking fittings at incoming receiving. These two operations require the fast and inexpensive testing accomplished only with conical ring and plug gages.
Since ISO 80369 has no gages; what can I use?
The good news here is that we offer conical gages designed following the design example of the ISO 594 gages. These gages test the conical surface MMC (Maximum Material Condition) and ignore any issues related to the LMC (Least Material Condition). Ignoring the LMC is acceptable for testing validated parts because any wear or damage to the mold or tooling will cause changes to the MMC, and the conical gage will find the change.
More Decisions to make: Ring with C'Bore; Ring with Handle; or 5-Newton Weighted Ring?
Ring with C'Bore
Not offered for ISO 80369 conical ring gages.
You may be familiar with the old ISO 594/1 ring gage style which had a C'Bore (counterbore) in place so that the ring gage could slip under the threaded collar and test the part. This gage style worked marginally well, but could not be made to test all ISO 594/2 parts. If the ISO 594/2 threaded safety collar was made to its MMC, it interfered with the bottom of the gage C'Bore.
We are not offering this style for the new ISO 80369 conical ring gages. ISO 80369 was initiated to develop non-interconnectable families of medical connectors. Part of the non-interconnectable design included more robust collars which make the simple conical ring gage with C'Bore infeasible to manufacture.
Ring Gage with Handle
The ISO 80369 conical ring gage with handle will completely clear the ISO 80369 collars in all cases. Basically the ring gage is manufactured as a thin wall tube, notched at the appropriate places and inserted in a handle. There two disadvantages to the ISO 80369 ring gage with handle: a) The historical best practice usage of the conical ring gage requires the application of the gauge with 5-Newtons of force. Some verifiable method of developing 5-Newtons of force must be implemented with each application of the gage. b) Because it is a hardened stainless steel thin wall tube with a notch cut out of it; it is easily damaged while if mishandled. Threat the conical ring gage like an expensive sensitive piece of equipment and the chance of damage will be greatly reduced.
5-Newton Weighted Ring Gage
The 5-Newton Weighted Ring Gage is the Ring Gage with Handle with added weight so that the historical best practice usage application force of 5-Newtons is met with just the application of the gage. The 5-Newton Weighted Ring Gage will completely clear the ISO 80369 safety collar in all cases.
With Or Without 5 Newton Weight?
This is an internal decision for you to make.
We recommend with the 5 Newton weight because:
1. The historical best practice (initiated in ISO 594/1) demands that the conical ring gauge be applied to the part with a force of 5 Newtons.
2. Application of the 5 Newton force is an inaccurate cumbersome operation if the 5 Newton weight is not integral to the conical ring gage.
3. The test results can easily be falsified or skewed depending on how much unregulated force is applied to the conical ring gauge.
4. If you desire repeatable results from the conical ring gauge, then select the 5-Newton weighted conical ring gage.
Follow this link if you wish a more in-depth discussion on the 5 Newton force.
How to Apply 5 Newton Force
I cannot make this decision for you, but I will supply you with some thoughts about this topic for discussion. What ever you decide you need to support logically to whomever requests your reasoning for your method.
The 5 Newton weight (approximately 18 ounces/510 grams) could be considered a 'light' weight. ISO 594 did not apply a tolerance to the 5-Newton force. Since there is no tolerance defined; we have considered the 5-Newton force as a nominal value and have applied a conservative tolerance to that. We have converted the 5-Newton force to grams; we use 509.86 grams +/-0.75 grams.
What is a conservative Tolerance?
There is a 10% Tolerance Rule common in industry which basically uses 10% of the product specification as the tolerance. If we apply 10% of the 5-Newton weight as tolerance (5N+/-0.25N) we should have a conservative tolerance. There are many variables in the application of the 5-Newton force which can be controlled, but are illogical to control because of the expense involved in maintaining that control compared to the benefit of such stringent control. If this is the direction you wish to travel in using the ISO 80369 conical ring gage; we offer the gage assembly with 5-Newton total weight.
HISTORICAL RING GAGE USE PROCEDURE
The following data is extracted from ISO 594/1 and expanded
for further clarification.
5.1 Gauging Test: The procedure shall be carried out as specified
below in 5.1.1 to 5.1.4.
5.1.1 Carry out the test using steel gauges as illustrated
in ISO 594/1 Figure 3.
5.1.2 Carry out the test at a temperature of 20°C +/-5°C.
5.1.3 Prior to testing, condition products made from hygroscopic
materials at 20°C +/-5°C and 50% +/-10% relative humidity
for not less than 24 hours. Conditioning is not required for
products made from non-hygroscopic materials.
5.1.4 Apply the gauge to the conical fitting with a total
axial force of 5 Newtons, without the use of torque. Remove the axial load.
4.1.1 Gauging test results:
a. The small end of the male conical fitting shall lie between
the two limit planes of the gauge.
b. The larger end of the tapered portion shall extend beyond
the datum plane of the gauge.
c. Rocking shall not be evident between the gauge and rigid
material fitting undergoing test. This test for freedom from
rocking may also be found useful (not required) for evaluating
General Construction Data:
The Medi-Luer gage test product contact portions are made of 440C Stainless Steel and hardened to Rockwell C-scale: 56 to 58; the weight is made of 303 Stainless Steel. The use of hardened steel for gages is is not a requirement of any specification; however, we consider it best-practice to use hardened materials for gages so that you have the most reliable inspection tool. If you must have the materials of construction certified; this is considered a special request. There will be an extra cost, and the lead-time for the gage may double.
This data is provided for general information only. The intention is to provide accurate information; regardless; errors may exist in the supplied information. If accuracy is critical, base your final decisions on the data provided in the root documents: ISO594/1:1986; ISO 594/2:1998, ISO80369-7:2016, and ISO80369-20:2014; which are copyrighted documents.
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Original Posting: 1/11/2008
Last Revision: 4/30/2020
Error corrections in, or comments about, the above data can be sent to: email@example.com