Question 1

What is an API 11AX ball and seat?

Accepted Answer

API 11AX ball and seat are the critical sealing pair inside a subsurface sucker rod pump. The ball lifts off the seat on the up-stroke to let fluid enter, then seals on the down-stroke to push fluid upward. API 11AX is the API specification that defines their dimensions, materials, and performance.

Question 2

What materials are used for API 11AX ball and seat?

Accepted Answer

Common materials include 9Cr18Mo and 6Cr18Mo stainless steel, cobalt-chromium-tungsten alloy (Stellite), YG8/YG13 tungsten carbide, titanium carbide-based hard alloy, and non-magnetic nickel-based alloy. Selection depends on well fluid, sand content, temperature, and pressure.

Question 3

What is the difference between V11 and V13 ball and seat?

Accepted Answer

V11 and V13 are API 11AX valve series with different dimensional envelopes. V11 covers common pump sizes from V11-106 to V11-275. V13 is a larger, heavier-duty series for higher-volume or deeper wells. Both can be supplied in matching sets with material selected for well conditions.

Question 4

What precision can your API 11AX balls and seats achieve?

Accepted Answer

Our balls achieve sphericity within ±2 µm, surface roughness Ra 0.025 µm, and pass 100% vacuum seal testing at 85 kPa for 5–12 seconds. Seats are machined to drawing with OD Ra 1.6, end-face Ra 0.4–0.8, and sealing-line Ra 0.2.

Question 5

Can you make API 11AX ball and seat parts from my drawing?

Accepted Answer

Yes. You can send your drawing, and we can evaluate custom API 11AX ball and seat production based on your size, material, hardness, precision, and surface requirements. We will review the details and confirm whether your specification can be made.

Question 6

How do I choose the right hardness for a ball and seat set?

Accepted Answer

For general service, 9Cr18Mo at HRC 55–60 is standard. For sandy or abrasive wells, choose YG8/YG13 tungsten carbide (HRA 88–92) or Stellite (HRC 40–50). For corrosive low-abrasion wells, 6Cr18Mo or non-magnetic nickel-based alloys work well. We recommend based on your well fluid analysis.

Bola de acero inoxidable

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