DIN/ISO/ANSI/JIS What are they?
- DIN – Deutsches Institut für Normung (German Institute for Standards)
- The vast majority of metric fasteners are presently manufactured to this standard which was created long before ISO standards. There are DIN standards for just about everything. DIN standards are currently being revised to more closely match ISO standards. For ordering fasteners all you need is:
- The DIN( which defines the style of the fastener)
- The material desired (i.e. 8.8 Steel, 316 Stainless, Hastelloy C276)
- The coating or plating (if any)
- ISO – International Standard Organization
- Founded in 1946 this organization publishes standards which individual countries have to vote on and are asked to apply. Currently ISO is comprised of more than 90 member countries. ISO’s standards for metric fasteners are rapidly gaining more recognition and in the years to come will probably become the world standard.
- ANSI – American National Standard Institute
- A US organization that has developed standards which are essentially in agreement with ISO standards.
- JIS – Japanese Industrial Standard
- Although mainly based on DIN, some standards have been modified based on the needs of the Japanese market. Fasteners used in most electronic equipment manufactured in Japan fall under the JIS standard.
All of the standards listed above detail an items’ dimensional specifications and material content. These standards are accepted worldwide and ensure you that any items that are ordered according to a particular standard will meet the specifications in compliance to the listed standards regardless of the manufacturer. Although there are many different standards for metric they are all manufactured to the same thread. The DIN spec may call for a certain head dimension and ANSI spec another but a 10×1.25 ANSI hex bolt will always thread into a DIN 10×1.25 hex nut and vice versa.
What is thread pitch?
Metric screw threads are identified by the capital letter M, followed by the nominal diameter which can be further defined by the thread pitch. If no thread pitch is specified the thread is assumed to be coarse thread.
|Metric Coarse Thread||Metric Fine Thread|
The pitch is the distance from one crest of the thread to the crest of the next thread.
Please see our Technical Information section for thread pitch identification charts.
What do the markings on the head of a fastener indicate?
For metric fasteners there are usually 2 pieces of information.
- A manufacturer marking which simply indicated the company that manufactured the fastener.
- The strength class which consists of two numbers separated by a decimal point. Common classes are 4.8, 8.8, 10.9, and 12.9. The number of the left indicates 1% of the tensile strength in MPa, or N/mm2. The number on the right indicates the proportion of the yield strength in relation to the tensile strength.
|Example for Class 12.9|
|Left Digit 12 (Tensile Strength)||Right Digit .9 (Yield Strength)|
|12 x 100 = 1200 MPa = 1200 N/mm2||.9 x 1200 = 1080 MPa = 1080 N/mm2|
|Conversion factor for psi = 145
1200 MPa x 145 = 174000 psi
|Conversion factor for psi = 145
> 1080 MPa x 145 = 156600 psi
Are you ISO certified?
Yes. Fuller Metric Parts Ltd. is ISO 9001:2008 certified (certificate number CA1617). As a distributor, we have always taken great care in purchasing to ensure that our vendors supply goods which conform to quality standards. Information on our quality system.
What is Rohs?
Restriction of Hazardous Substances (Rohs)
The purpose of this initiative is to eliminate harmful materials from the waste stream for consumer electronic products.
What is Fuller Metric’s procedure in complying with Rohs?
Fuller is an importer and distributor of fastener products and industrial supplies. We are not the manufacturer and do not have any plating facilities. We rely on our international vendors to supply us with compliant parts. We now require all our vendors to supply us with Cr6 free parts, this information is documented on all the paperwork and traceable through to the final packaging process. Our internal processes and labelling procedures have been modified to retain this information.
In the fastener industry, although we try to turn out inventory several times per year, many items are maintained in large quantities and turn less often. There are thousands of SKU’s that are affected and it will take some time to totally resolve this problem.
Until these supplies are exhausted we can only individually qualify each item you require, this can be done at some reasonable expense.
What materials are we talking about?
- Cr+6 (Hexavalent Chromium called Cr6 hereafter)
Cr6 is used in zinc plated fasteners as the topcoat finish primarily for yellow zinc.
Which industries does Rohs affect?
Only consumer electronic equipment is covered by the directive, products only used in commercial applications are excluded. Our customers must specifically ask for compliant product. We are only responsible to supply what they ask for at the time of purchase.
What fasteners are affected by this initiative?
Zinc Plated Fasteners with a Chromium top coat. Plain Steel and Stainless Steel themselves may contain trace amounts of these materials but are compliant as long as they are homogeneous (This means they cannot be mechanically disjointed into different materials). Generally all fasteners that are not plated will comply.
Are all plated fasters non-compliant?
No, only certain coatings contain Hexavalent Chromium. The zinc coating on fasteners also needs protection from corrosion with a sealing product. Yellow and some other colored finishes contain Hexavalent Chromium. Clear zinc does not contain any Hexavalent Chromium that is intentionally added.
Why is the phrase “intentionally added” important?
Trace levels of these materials are allowed as long as they are not intentionally added to provide a specific characteristic to the product. Some contamination is possible at any step from initial manufacturing, plating to packaging. The key is that if these materials are not intentionally added then some small trace amounts are allowed.
Why use Hexavalent Chromium?
This product adds significant corrosion protection, up to 3-4 times compared to clear zinc alone. No direct replacement is available at this time with identical properties.
What is the best way to comply with Rohs?
Use Stainless Steel on items that need to be compliant, no testing or certification is required.
If plated steel fasteners are required how do we comply?
Clear Zinc fasteners comply with Rohs as well as some other coatings. The Manufacturer or Metal Finisher has to certify the product used complies.
Can we certify products in stock without Manufacturer or Metal Finisher certificates?
No, we can only state that no Hexavalent Chromium has been added intentionally and the goods should comply. For certification each lot will have to be tested for compliance.
If we have a certificate from a Manufacturer or Metal Finisher can we certify the product?
Yes, when our supplier certifies the goods then the liability now transfers to the supplier.