I have a question regarding ASTM A519 wall thickness tolerance. The wall thickness tolerance says
- If OD is less than 3”, the tolerance is 12.5% when the WT < 15% of the OD and 10.0% when WT > 15% of the OD.
- If OD is 3” to less than 6”, the tolerance is 10% when the WT < 15% of the OD and...
I have an application where I need to grip onto the OD of a tube with jaws/slips to resist an axial load that is applied to the tube. There will be three or five jaws equally spaced around the OD to clamp. In order to size the hydraulic cylinders that will provide the clamping force I need to...
I need to select a stainless steel grade for a cryogenic application. We use liquid nitrogen to drop the temperature of a steel pipe in order to remove an lining inside the pipe (differential thermal expansion causes cracking & thus removal). We load the tank with steel tubes at room...
I am trying to redesign an existing piece of outdoor structural equipment and bring it in line with code. I have two options to rework a deficiency where a square HSS member joins to a plate with a fillet weld around the square HSS:
1. Replace an 1 1/4" A36 plate with a ~80 ksi plate. Likely...
This may be a simple question but it has me stumped. I am trying to find the equivalent ASTM Axxx number for API tubing/casing (eg:5CT J55). Does an equivalent ASTM number exist? I have reviewed the API specs I have and found no such cross reference.
The reason I ask is that I am trying to...
I have a PTFE (graphite filled) seal that I am testing running on a 2" shaft @ 500 RPM, 500 Psi. Test fluid is water at 50°C. It is grease lubricated. We are measuring temperature near the seal of 150°C which seems ridiculously high to me. Are you surprised by the temperature? I would never...
I need to find the spring constant (or load vs. deflection curve) for a piece of wire rope (1/4" 7x19 in my case). Surprisingly this is not something that any vendors publish....only breaking strength. I suppose the published data makes sense for the typical application where you are...
I have a device that is attached to the wellhead. It transmits a large bending moment, axial load, and some shear to the casing and wellhead. I would like to know what the max allowable load/stress for a given casing / wellhead flange combination is? I have looked over some of the API specs...
Can someone tell me if there is an API spec that governs what material must be using for a structure that mounts to a producing wellhead that will operate at low temperature(-40C)? I have API 4F that covers the structure but it makes no mention of material requirements for low temperature. I...
I am building a piece of test equipment that has five housings (approx 6" OD x 3" thick) bolted together. On each end of the bolted together housing assembly I have ball bearings which guide a shaft through the housings. I am trying to maintain the housing to shaft concentricity as tight as...
This may be a simple question, but it PTFE incompressible? I have a graphite filled teflon material used for a lip seal and want to do some preliminary analysis. I need to know the poisson's ratio of the material. I have some experience dealing with elastomers but little experience with PTFE...
I am looking for a method of measuring runout on a shaft while it is rotating. The shaft will be approx 2" diameter, rotating 500RPM, and there may be a film of grease on OD of shaft. There is a small 1/4" dia hole providing access to the shaft from a housing that covers it. For a "static"...
I am doing an advanced FEA analysis that involves permanently forming a copper water pipe (C12200 ASTM B88). My problem is that I cannot find any DETAILED stress-strain curve information that includes the nonlinear yielding portion of the curve....all that's normally listed in elastic modulus...
Does anyone know if there is an API spec that details the hoop stress calculations for a sucker rod coupling? It would be useful for some other threaded connection designs Iam working on but can't seem to find that kind of calculations in the spec I have.
Thank You
I am working on building a spreadsheet for threaded connection design. It is for an oilfield application (or others) where you need to join two coaxial shafts together with a cylindrical coupling. The coupling has to transmit a torque and axial (tensile) load between the two shafts. One of...
I am going to try hydroforming a copper water pipe into a new shape. My question is, how much will standard copper water pipe strain harden when formed? I looked and in Canada the spec is ASTM B75-C12200. My info says that is 99.9% pure copper.
Does anyone have any ideas of the hardening of...
I am reading some articles from Axel Products re: tests for specifying elastomer properties for FEA. I am confused about the planar shear test. This is the test that looks like a very wide tensile specimen. My ASCII art below shows the specimen and the axis orientation.
^ Y-Axis
|...
I need to begin to venture into analysis of elastomers. I have only used (hate to admit it) Mechanica to date along with some experimentation using Ansys. Abaqus keeps coming up when I search for elastomer FEA. Problem is, I am not a PhD...only a B.SC ME. I have what I consider a good...
I am trying/learning via a simple 2d plane strain (solid182) free thermal expansion problem. I have applied a temperature to an area and solved for the thermal expansion. Works as expected...although the whole TUNIF and TREF still has me a little confused...looks like the delta T used for...
Probably a simple question, but for a newcomer it's still confusing.
I want to display all of the symbols for loads, constraints, etc ALL THE TIME. When I apply a constraint, I see the symbols showing it has been created. After doing a few more operations those symbols disappear. I would...
