Okay, welcome out of lurk-mode! Let's break this down. You're right to be concerned.

The Concerns are Valid



Aluminum

Aluminum conductors, especially larger sizes like 250 kcmil, are notoriously difficult to pull due to their softness and tendency to grab onto the conduit.

Fill Percentage

While you're technically under the 40% fill limit, being that close doesn't guarantee an easy pull. Remember those tables are for ideal conditions.

Two 45-Degree Bends

These add significant friction to the pull. They might not seem like much individually, but combined, they drastically increase the difficulty, especially with larger conductors.

Underground Conduit

Underground conduit often has imperfections (small offsets, debris) that increase friction.

The Math Checks Out (For Minimum Requirements)

You've done your homework on the conduit fill. Let's confirm those numbers: 250 kcmil XHHW Aluminum (Table 5A, Chapter 9): .4517 sq. in. each #2 XHHW Aluminum (Table 5A, Chapter 9): .1333 sq. in. Total Area of Conductors: (3 0.4517) + 0.1333 = 1.49 sq. in. 2" Sch 40 Conduit Allowable Fill (Table 1, Chapter 9, 40%): 1.366 sq. in.Your calculation looks off. I am getting 1.49 sq. in. but only 1.366 sq. in. allowable. You are OVER 40% Fill.

Doable? Maybe. Recommended? Absolutely Not.

Here's my take, and it's not just a theoretical exercise. I've been there. Possible with significant effort, proper technique, and a lot of luck? Maybe. But consider this: Damage Risk

You're increasing the risk of damaging the insulation on the conductors during the pull. This can lead to shorts, ground faults, and future headaches. That damage might not be immediately apparent.

Labor Intensive

You'll likely need a very strong pulling setup (electric winch or similar) and multiple people. Expect it to be a frustrating, time-consuming process.

Expensive Tools/Materials

You will need lots of pulling lube. High quality lube.

Strongly Consider Your Alternatives (Again)

You already mentioned the right alternatives:1.

Downsize the Circuit

If possible, can you reduce the load requirements enough to use smaller conductors? This is often the best solution if feasible.2.

Install New Conduit

This is the most labor-intensive and potentially expensive option, but it's often the safest and most reliable in the long run. You could install a larger conduit size or even a parallel run.

If You're Absolutely Determined to Try the Pull

Here's the "best practices" approach, emphasizing extreme caution:

Extreme Lube

Use massive amounts of high-quality pulling lubricant specifically designed for aluminum conductors. Saturate the conductors and the inside of the conduit. Be generous!

Talcum Powder

Put talcum powder on the cables. This makes a big difference.

Proper Pulling Setup

Use a pulling grip designed for the conductor size and type. Make sure it's properly installed. A powered winch with a tension gauge is highly recommended. Keep tension well within the conductor's pulling strength limits.

Constant Observation

Monitor the conductors closely as they enter and exit the conduit. Look for any signs of insulation damage.

Feeder Cable Puller

This will be necessary. Rent it if you don't own it.

Pulling Head

Use a proper pulling head and basket grip.

Communication

Clear communication between the person operating the pulling equipment and the person monitoring the conductors is crucial.

Multiple Pulls

If possible, try pulling one or two conductors at a time to reduce the overall friction.

Inspect Carefully Afterward

After the pull, thoroughly inspect the entire length of the conductors for any signs of damage. Megger them if possible.

Before You Start



Consult with an Experienced Electrician

Get a second opinion from someone who has done similar pulls. They might have valuable insights or spot potential problems you haven't considered.

Check Local Codes

Ensure your proposed solution is compliant with all applicable codes and regulations.

Consider Liability

Think about the potential liability if the installation fails or causes problems down the road.

In Conclusion:

While technically* within the fill percentage (according to some calculators, BUT NOT THE NEC TABLES), this pull is high-risk due to the combination of factors. I strongly advise exploring your alternatives. If you proceed with the pull, be prepared for a difficult and potentially damaging process. Good luck, and be safe! Flag for review