CPCs ARC/HRC/ERC/WRC linear guide series’ use four rows of re-circulating steel balls arranged in the O-shape design and at 45º contact angle with the raceway. This achieves superior load capacity and track rail rigidity compared to other linear rail manufacturers.

If the number is negative, the opposite is true: F2B is ahead of F1, an a case can be made that ‘opting out’ of F2B and staying in F1 is the best course of action.

Linear motion components with rolling element linear bearings, such as profiled linear guides, linear shafts and bearings, crossed roller bearings and ball screws have two different load capacity specifications. These are static and dynamic load capacity. When looking at static vs dynamic load capacity, these should be evaluated independent of each other as they are based on different operating parameters and performance criteria. Understanding the difference between them, as well as understanding ball bearing arrangement, is essential to suitably size and select the correct linear motion product.

Static loadexamples

Simply put, when looking at static vs dynamic loads, a static load refers to stationary loads, when the linear component is fixed or stationary. A dynamic load will involve movement of the carried load.

Static vs dynamic loadcalculator

Static load capacity will nearly always be higher than dynamic load capacity. As the load is being applied to the bearing in a static, stationary non-moving state (or very slow moving) the failure point is limited to deformation of the raceway material and the ball bearing.

The problem is that the Covid-19 pandemic created at the NVC a backlog of Worldwide F2B cases that are ‘documentarily qualified’. So the question becomes, how quickly are the associated interviews scheduled?

The incredibly sad news here is that family Green Cards that were not issued over the last two years are gone forever. They are not coming back for family (they were transferred to ’employment’ based Green Cards). As a result, time to current will go up:

The dynamic load capacity is used to determine the rated life of a linear rolling element bearing. This is commonly referred to as the L10 life. So called L10 life as it is the life that 90 percent of a group of identical bearings is expected to achieve under set conditions of speed and load.

Difference betweenstatic loadanddynamic loadPDF

Time to current measures the time it takes an applicant to have their ‘priority date’ current when compared to the ‘final action date’ of the Visa Bulletin. Although not factually correct, time to current is often used by applicants as an estimation of how long it is going to take them to get their Green Card. We also make predictions about time to current for our Green Card dynamic timeline predictions: the process of scheduling a Green Card interview cannot be initiated before the applicant’s date is ‘current’, so it is one of the key ‘anchor’ of the process.

The design of ball bearing raceway arrangement is key when manufacturers define static and dynamic load capacity. All linear motion manufacturers will list their static and dynamic load capacity ratings, but not all linear guides were created equal. Let’s look at the difference between raceway arrangements. Linear rails and guides should always offer good travel accuracy and high stiffness. They can withstand downward, upward and side loads. They can also withstand overhung, or moment loads. The larger the rail, the more moment capacity it has of course, but crucially, depending on the raceway arrangement, ‘O’ or ‘X’, this directly impacts the moment loads the linear guide can withstand.

We expect to update our predictions the day after the next Visa Bulletin is released. Our best guess as to when we will update these predictions is as follows: Oct 15, 2022

Dynamic load capacity, C, is based on observational testing in which a load that is constant in size and ‘normal’ to the load carrying ball bearing surfaces allows the bearing to achieve a defined travel distance for linear guides or number of revolutions for ball screws without any signs of fatigue. Any flaking on the surface of the raceway material or the linear rolling elements is defined as fatigue.

The application should always be considered when considering static loads. Linear product manufacturers recommend applying a static safety factor depending on the operating conditions. This factor is the ratio between the maximum static load and the basic static load rating. If the linear component is to operate under smooth conditions with low risk of vibrations this can be as low as 2, with a factor as high as 5 or 6 if the application conditions have severe shock loads and, or vibration.

FY2020 is the year where the Covid-19 pandemic hit, and the weirdest thing happened: the Visa Office of the U.S. State Department advanced the F.A.D more rapidly during the second half of FY2020 (from April to September 2020) then it did during the first half of the year (from October 2019 to March 2020). In other words, the F.A.D. (Graph A.) advanced more after the pandemic started than before!

Don’t see your Priority Date? Want to know when your Interview will take place? Get a detailed, personalized Timeline with Date Predictions for each step.

F2BLatest Visa Bulletin Date:Oct 2022Chargeability:allCountriesFinal Action Date:Sep 22, 2015Movement:None Fiscal Year 2020 and 2021 have essentially been on par with the average of the last decade, even when the number of F2B interviews was severely reduced by the pandemic. As a consequence, there is a backlog of worldwide F2B applications that are either already ‘documentarily qualified’ at the National Visa Center (NVC) and the State Department will need to go through that backlog before we can see the dates move forward again.

The L10 life calculation and dynamic load capacity are again defined by the ISO 14728-1:2017 standard for linear bearings, and by the ISO 3408-5:2006 standard for ball screws. The ball screw standard specifies that dynamic load capacity is based on an L10 life of 1 million revolutions. The linear bearing standard for dynamic load capacity specifies an L10 life of 50,000m or 100,000m. CPC (Chieftek Precision Company) have market leading static and dynamic load capacities due to their innovative linear guide ball arrangement allowing in many cases for the designer to choose a lighter linear product with smaller dimensions than other manufacturers. All calculations and important specifying information are available through Kiwi Motion.

Our latest predictions for the Final Action Dates of F2B for ?All Countries. Children of Green Card holders who are adults, but not married.

Static load vs dynamic loadbearing

In order to fully understand where we are with F2B, we need to go back to Fiscal Year 2019 (FY2019), which took place from October 2018 to September 2019. At the time, it feels like the Visa Office was unhappy with the ‘response rate’ to the Welcome Letters sent by the National Visa Center (NVC). In other words, they felt that not enough applicants were submitting forms and documents, and moving towards being ‘documentarily qualified’ (or ‘interview-ready’). As a consequence, they moved the F3 worldwide Final Action Date (F.A.D.) forward very rapidly during FY2019, making it the best in the last 20 years.

Some F2B applicants have the option to become F1 applicants when their sponsor naturalize. The great advantage of becoming F1 is that your Green Card application is no longer terminated if you get married (as an F1 you are switched to F3).

The following graph represents F1 minus F2B. If F1 minus F2B yields a positive number, then it means that the Final Action Date for F1 is ahead of the F2B one, and F1 has the advantage (and applicants should welcome the switch to F1).

Static vs dynamic loadreddit

The ‘O’ type arrangement provides a larger moment arm and gives higher moment load capacities as well as providing equal load capacity in all directions.

Yes, obviously the decade of 2010 – 2019 is significantly slower than the 2000 – 2009 one, which means that the pace of advancement of F2B is slowing down. But the point here is that FY2020 and 2021 have essentially been on par with the average of the last decade, even when the number of F2B interviews was severely curtailed. So what did we see? We saw the best year of the last 20 years (FY2019) followed by two years on par with recent averages that took place when not that many Green Card were issued. The consequences of this sequence of events is easy to understand: there is a backlog of worldwide F2B applications that are either already ‘documentarily qualified’ at the National Visa Center (NVC), or that are on the verge of being so. The State Department will have to go through this backlog of interviews before the F2B F.A.D can start moving forward again.

But if marriage is for reason or another not a concern as an F2B applicant, and your sponsor gets U.S. Citizenship, you have the option to ‘switch’ from F2B to F1, or they can ‘opt-out’ and stay F2B.

Static load capacity, C0, is the amount of load a linear rolling bearing can withstand before the sum of the raceway deformation and of the ball equals 0.01 percent of the ball diameter. This is defined by ISO 14728-2:2017.

Switching to F1 used to be an obvious choice. For the last few years however, ‘opting-out’ and staying in F2B has been the way to go.

Static loadanddynamic loadexamples

In conclusion, when assessing linear motion components such as profiled linear guides, linear shafts, and ball screws, it’s essential to differentiate between static and dynamic load capacity. CPC’s ARC/HRC/ERC/WRC linear guide series, featuring an O-shape ball bearing arrangement, demonstrates superior load capacity and rigidity. Understanding the nuances of static vs. dynamic load capacity and the importance of ball bearing arrangement is crucial for precise sizing and selection of linear motion products.

Static vs dynamic loadformula

The ‘X’ type arrangement does provide equal load capacity in all directions as per the ‘O’ type design; however, it results in a shorter moment arm where overhung loads are applied thus reducing moment load capacity.

Static loadanddynamic loadcalculation

So let’s see how the last two Fiscal Years did when compared with the averages of prior decades. Here we are comparing the last two Fiscal Years (2020 and 2021) in red with an average of the last decade (2010 – 2019) that is shown in green, and the average of the decade before that (2000 – 2009) that is shown in blue.

The Green Card Interview can be scheduled when the applicant’s Priority Date is ‘current’ (when compared to Chart A of the Visa Bulletin, Final Action Dates for Family-Sponsored Preference Cases), and the applicant’s case has been declared ‘documentarily qualified’ (so-called ‘DQ’, also known as ‘complete’ and ‘interview-ready’), by the National Visa Center (NVC).

Applicants going through Adjustment of Status are often allowed to use the ‘Filing Date’ of the Visa Bulletin to determine when they are allowed to file Form I-485. Here is the latest: Filing DateMovementStatus Jan 8, 2015+5 weeks✔︎ Yes, the Filing Date can be used

Your Plan, Instructions, Forms (including Affidavit of Support) Get your personalized Green Card Plan, detailed instructions, and online USCIS Forms (including Affidavit of Support Form I-864EZ, and Medical Form I-693) with automatic error detection.

In order to answer this question, Immigration Planner has carried out an in-depth analysis of U.S. Department of State data, building a database of all the Consular Green Cards issued since October 2018 at the ~150 U.S. Consulates and Embassies which issue family Green Cards outside the United States (the ‘raw’ data from the State Department can be found  here).

The O-shape design allows the use of larger steel balls in greater quantities to increase the load capacity, moment capacity and rigidity. This allows the machine designer to use a smaller product, so vitally important when trying to reduce overall machine weight and to save on purchasing costs.

The key of our short-term prediction is that there will be no ‘forward movement’ for F2B-All Countries until September 2022, at the vert least. This has been stated numerous times by Charlie Oppenheim, who is the head of the ‘Visa Office’ that makes the decision about the Visa Bulletin (you can listen to him talking about the family preferences in November 2021 at  on this Youtube video).

You are going to have to use our web app to get longer terms predictions (which is free, and it takes only a few minutes to get results), but this will give you a sense of where we see things going in the short term –>

The issue with is that the number of consular F2Bs issued in Fiscal Year 2022 is 43% lower than it was pre-pandemic. Check out the details per consulate: