Quality Bolts

By flamin

Date 05-27-2011 17:37

I could see that happening with a grade 2 bolt. What grade is that?

By Cumminsguy71 (*****)

Date 05-27-2011 17:40 Edited 05-27-2011 17:47

here's another pic.

"SAE J429, Grade 2, has a tensile strength requirement of 74,000 PSI and the ASTM A307 Grade A only has a tensile strength requirement of 60,000 PSI. This means that SAE bolts have a 23% higher strength requirement than the ASTM bolts in the 1/4 through 3/4 diameter range."

According to what I've found A307 is rated at 60k psi, not thinking I put 60k on with a standard length wrench and a cresent wrench though. These were bolt packs or "flange packs" with bolts and gasket for 3" flanges.

By flamin

Date 05-27-2011 17:47

ASTM 307 grade A has about a 60KSI tensile. It's basically a general purpose bolt. Something you'd find at home depot.

By fschweighardt (***)

Date 05-27-2011 19:58

That looks like a crappy upset job on the head, some kind of cold lap in there and maybe upset at a low temp or something

By DaveBoyer (*****)

Date 05-28-2011 02:31

Doing a little math, 5/8" diameter made from 60KSI material should fail at 18,407# load. I would expect the bolt to fail at the junction of the threaded part and the body diameter. Perhaps there was some issue with the head upset. This is done cold on bolts like this

Short of testing, it is hard to tell what load it actually failed at.

An SAE Grade 2 bolt is pretty much the bottom of the barrel, so an ASTM A307 grade A is the mud under the barrel.

Do they give any elongagation specs for these bolts?

I take it this is a bolted pipe ? Pehaps there was more load on the bolts than the pre load You tightened them to from the pipe warming or cooling and trying to deflect.

By Cumminsguy71 (*****)

Date 05-28-2011 02:42

Not sure Dave. We don't even have the system up yet and I make sure they alternate on the tightening sequence. From what I've found the torque is around 80 ft/lbs. I've seen lots of over torqued bolts and the elongation in the threads but the head just popping off just odd. Called the supplier we got the kits from and he was going to contact his guy. Said they were Chinese or Taiwan made bolts. From what you said, "mud under the barrel" these are some cheap arse bolts.

By DaveBoyer (*****)

Date 05-28-2011 03:20

It is a good chance that You will be using imported bolts, as US made is a whole lot more money. BUT there are better made import products, and worse ones.

As a mechanic, I am sure YOU understand about bolt tightening sequences.

If a goober ran one bolt down tight with the other side gapped open [depending on gasket & face configuration], the leverage when the open side is tightened increases the load on the first tightened bolt drasticly.

By CHGuilford (****)

Date 06-01-2011 16:10

It looks like those bolts are made of case-hardened peanut butter.

By Cumminsguy71 (*****)

Date 05-27-2011 21:20 Edited 05-28-2011 12:18

I told the guys on the job they keep popping I'll run to Caterpillar and get some grade 8 Cat bolts, those won't break! He said, I wouldn't spend my own money, they just buy the cheapest stuff to get by with. Told him I'd rather spend my own money than get blamed when one of these cheap arse bolts pops, or all of them when they get a 3" line turned on full of water!

By Pat

Date 05-28-2011 11:25

At work we are in the process of getting rid of our present fastener supplier along with all the junk they have over stocked us with. I believe management is in discussions with Lawson, who I believe have fairly good quality products. The present one must search high and low for the cheapest crap they can find. The washers they have been supplying are a crap shoot on the thickness. Some of the same sized washers will be half the thickness of others out of the same batch. I had ordered some 3/8" grade 8 cap screws for a project. A Mech on another shift started using them, and left me a note along with some twisted off ones stating that they were of lesser strength than the grade 5 in the cabinet....he was not kidding. I can't wait for Lawson, or whoever. Also, the present place seems more concerned about selling their used fleet vehicles than fasteners.

By warmka weld (*)

Date 05-28-2011 13:36

They based out of winona mn? Very hard to get a bolt and nut to thread together without a wrench from those guys. Very poor quality.

By Pat

Date 05-28-2011 17:33

I believe they are headquartered in Winona. I am beginning to wonder if they import most of their fasteners because quite a bit of the items we have gotten lately have that not so finished finish to them like a lot of the Chinese fasteners have. The Lawson reps that showed up left some bolt samples that have a good quality finish and look like they may be USA made.

I have heard, but have no concrete information about it, but I guess all fasteners are supposed to meet several standards. In other words if I buy some bolts that are grade 5, it should not matter where they are from because they have to meet the grading requirements..........I don't know about this. Who is to stop a place from making or importing inferior fasteners. Where I am at, the Farm & Fleet stores carry some good quality fasteners made in Rockford, IL. The Lowes stores carry fasteners (junk) that state they may be from 1 of about 20 different countries. It is really sad that just about everything is imported to save manufacturing costs, but it costs you and I the same or more. Some of these corporations must be making a killing on this crap.

By 803056

Date 05-31-2011 21:03

Why are SAE bolts used on an ASME project? Or isn't it an ASME project.

Assuming the applicable code is an ASME B31.X, I would expect all bolting materials to be complient with ASME fastener, i.e., ASME B18.2.1 and B18.2.2, specifications, not SAE or ASTM fasteners.

Best regards - Al

By Bob Garner (***)

Date 06-01-2011 15:29

The symbol below the grade marking is supposed to represent the manufacturer for traceability. But the Chinese are known to copy American company symbols on their bolts.

By Cumminsguy71 (*****)

Date 06-02-2011 00:28

Hmmmm, not sure about that one. They supply all materials I'm there to ensure the gaps between pipes don't leak water. Interesting point though.

By FixaLinc (****)

Date 06-04-2011 03:48

Lawson use to have all better bolts but their smaller sizes now and some of their others are imported now. Some smaller machine bolts I got from Lawson & Rockford both had tags in the box listing about 5 countries none were the USA of where they could have been made. Rockford bolts are probably all imported now. Had bolts breaking on a loader years ago and tried many others even the bolts Case said to use failed but finally tried Lawson and those didn't fall out or break again. Many USA truck company builders were having problems with counterfeit bolts and recommended Lawson bolts to their dealers and required them to keep some on hand for steering box replacements and other chassis bolts.

http://www.lawsonproducts.com/webapp/wcs/stores/servlet/Home?langId=-1&storeId=10001&catalogId=10001&ahome=N

By A_DAB_will_do (*)

Date 06-01-2011 19:32

There's a million things that can go wrong with bolts when they're being made. Cheap suppliers don't do all the right steps in manufacturing or quality control.

If you look at the photos of the broken bolts you can see a couple interesting things.

First, I'm color blind, but the surfaces of the breaks look like they have light rust/red discoloration. If this is true, then the bolts cracked a long time before you ever put a wrench to them. High strength fasteners are heat treated to achieve the right strength. If the quench and temper isn't done correctly, the bolts can crack as they cool.

Second, usually bolts fail from cracks starting where the head meets the shank of the bolt, or from cracks starting in the bottom of the threads. These might have started from where the head meets the bolt shank; its tough to tell for certain. Bad forming operations can leave defects, just like undercut on the toe lines of a weld that will cause bolts to fail prematurely.

Third, and really interesting, in the photo you can see some hair-fine lines that radiate from the center of the fracture surface like spokes on a wagon wheel. These lines are often a sign of fatigue. I can't say for sure if these are fatigue failures from the photos posted, but that would be odd to see on a brand new bolt. Any chance these were re-used somehow?

Lastly, the bolts look to be coated. If the coating is an electro-plating or hot dip galvanizing, then the bolts can be damaged if they aren't properly baked immediately after the coating process is done. Hydrogen embrittlement can cause just the kind of cracking and failure you're seeing here.

Other than mis-use, all of these failure modes are signs of poor quality manufacturing. It would take a more detailed examination by a metallurgical lab to say for certain why these failed, but the odds definitely favor failure by bad manufacturing practice.

It's not just bolts these days. I have seen flanges crack, brand new parts that won't thread together, and poor fitup (out of round) all from imported pipe fittings...

Just my $0.02....

By Tommyjoking (****)

Date 06-02-2011 00:55

I just want say metoo More then likely or as already said Bolts from the FAR EAST. Metallurgy but especially sound repeatable manufacturing practices are just not there....but if I knew the bolt come from Japan I would not hesitate to use it. I have been having the same problem on different things for the last couple of years especially. I bought 10 pounds of "grade 8" 1/2 just last year that snapped like they where made of melted down ceiling fan parts...at the head mostly.....I quit using them after the fifth break (yea I am stubborn). I think most ma and pop hardware and even bolt suppliers have switched or offer a cheaper line...you can guarantee they are Chinese or Taiwanese. I reckon if it has got to hold you should expect traceability paperwork these days like your working to ISO standards.

By MBSims

Date 06-02-2011 02:37 Edited 06-02-2011 02:39

Very good observations. The photos almost appear as if a threaded stud was welded to a piece of hex stock, but hopefully that is not the case. I would love to have a couple of those failed and unfailed bolts to cross-section, polish and etch to see what the grain structure looks like.

Another manufacturing issue is bolt heads that are not perpendicular to the shank. One side of the head may bear against the members being joined while the opposite side is not even touching. This places a bending load on the bolt which will cause this type of failure.

The Fastener Quality Act was intended to stop the flood of counterfeit bolting coming out of Asia and other countries. Here is a link to some educational info on this federal law:

http://www.nist.gov/pml/wmd/metric/fqa.cfm

By MBSims

Date 06-02-2011 02:47

For what it's worth, I did not find the insignia shown on the bolt head above in the FQA Registry (http://www.uspto.gov/trademarks/law/FQA_Registry.pdf). I have another index at work that I will check tomorrow.

By 803056

Date 06-02-2011 03:12

You never told us what piping code was applicable. That is an important consideration because the fasteners have to comply with the requirements of the applicable code.

Whether you are checking welds, structural steel, or bolted flanges, it is important to check the materials against the project specifications, applicable codes, and drawings.

Designers and engineers are human. There are competent people and there are those that are less competent. The inspector is the safety net to verify the PS, codes, and drawing requirements are met in all respects. The improper selection of materials could be intentional or an oversight. A quick RFI could clarify the situation.

Until the question is asked, there is no way to determine if the supplier provided something ”better” than what was asked for. Suppliers are notorious for supplying material that is in inventory rather purchasing the “right stuff” if they suspect no one is checking the purchasing requirements.

No vendor would ever think of supplying inferior materials, but that is just one of the many functions performed by the inspector; to provide verification the proper materials are used.

Best regards - Al

By Cumminsguy71 (*****)

Date 06-02-2011 12:18

Your right about that Al. I've contacted the place where we got the bolts from and sent the bolts back to him so he can get with the supplier and pull anything that is related in the batch if needed. I understand what your saying about the code. ASME bolts will be stronger than ASTM for the application and so on. From what I've been reading though on bolt testing a bolt should never break like these two did though. I can't remember which I was reading but believe it was the ASTM and it stated if the bolt failed where the head meets the shank it was considered junk for the most part. I believe I also remember reading how it said the bolt, if it were to fail should fail at the threads or in the shank. I've stretched some bolts(Caterpillar) because we had upgraded torque specs on the 3200 series head bolts. We had to torque a 1/2" bolt to 110lb/ft. Talk about a bolt getting spongy! I've lost some bolts along the way doing that, in my learning curve you'd hear a ping. Pull the head and remove the busted bolt and try again. I do remember seeing the bolt where it stretched and was usually where the shank met the threads you could see the elongation.

I'm also sure there is a "cheap" factor involved as far as, uhm, the folks getting the material on the job to me and not talking about the guy who sells the material, the guy between the seller and me, LoL! I hear the employees talking while I'm there and it's sad. With me, I'd rather spend the money on top notch stuff, the correct stuff and never worry again. Some people get the cheapest dog poop available and by the time it's all said and done spend 3 times as much after all of the go backs and reworks. I know my welds are right, ASME and I fit everything the way it was called out on the print, i.e., this valve here, that one there and so on. Thanks for the info though Al, always good to have your input. Always learning something from your posts! (ok, no arse kissing intended!!)

Shawn

By Pickupman (***)

Date 06-04-2011 00:15

I had the same thought as MBSims. They look like they were two pieces at some time before they morphed into "bolts" and then back into their former state. Interesting problems you run into Shawn. Keep um coming. I learn alot from your projects. Thanks

By Cumminsguy71 (*****)

Date 06-04-2011 10:36

Thanks for the information MB, saved this stuff for future reference. Wish I had an extra bolt to send you. Gave them back to the salesman where they were bought at who is supposed to get them to the manufacturer so I'm officially out of the loop now. I'd like to hear what they found was the cause.

By Bob Garner (***)

Date 06-07-2011 16:32

I noticed the grade identification is "307A". All the A307's I've seen say, "A307" with the "A" preceding the "307". 'Bet these are counterfeits.

By Bob Garner (***)

Date 06-07-2011 16:39

Disregard my last post. ASTM A307 specifies the marking "307A".