octagonal ring joints.
octagonal ring joints.
(OP)
Can anyone give me any guidance on how many times you can safetly re-use an octagonal ring joint. At present I am getting conflicting information and i am opening out my options.
Thanks.
Thanks.





RE: octagonal ring joints.
Hope this helps.
saxon
RE: octagonal ring joints.
Many years ago, I worked for a major oil field service company that would reuse the rings and hammer the stud nuts tight. The stud bolts were never torqued, and as such, I have no idea if we were over tightening them. The same company did not change the packing on their coil tubing equipment as scheduled by contract. They saved $$ by not doing the job correctly. Fortunately, I had the good sense to quite before their reckless practices created an oil spill or injury while I was in the field.
Because you don’t know who tightened the stud bolts in the past, it may be good insurance to replace the stud bolts and nuts every time as well.
RE: octagonal ring joints.
I agree with Saxon. Joint rings are made of softer material than the flanges and are designed to "deform" to make the seal. When you loosen the flange they do not "recover" and as such it is dangerous practice to re-use the ring in a joint since it will not be located in exactly the same orientation and "local" irregularities will cause leakage. Always opt for a new ring and the sealing faces should be checked for damage.
RE: octagonal ring joints.
Just out of interest have any of you heard of KAMOS ring joints which are on the market.
RE: octagonal ring joints.
Thread378-96151
RE: octagonal ring joints.
RE: octagonal ring joints.
I have never seen a problem with the reuse of studs, B7 or B16, used in the above systems or any system where the stud has been protected from the enviroment. If a stud is tightened properly and has no physical damage there is no reason that it can’t be returned to service. The studs used in the above system have been reused many times and some are the old Crane alloy studs, precursor to B7, over 40 years old. I ran a dimension test on 1000 each of B7 & B16 studs that had been inservice many years by using a thread rolling die. There were only 2 that had been stretched enough not roll on the die. I conducted this survey 3 times over a 20 yr period.
The other half of the plant uses B8 class 2 studs were the reuse, probably 80% is more limited by damage, mainly galling. The original B8's had a much lower reuse factor for the above reason plus having more that had been stretched.
RE: octagonal ring joints.
RE: octagonal ring joints.