Choke Bean Sizing Guide
A choke bean is a calibrated hole. Order the wrong bore and the flow rate you record is not the flow rate you have.
A choke bean is a calibrated hole. Order the wrong bore and the flow rate you record is not the flow rate you have.
What A Choke Bean Does
A choke bean is used in the positive choke valve for controlling flow. On one side of the choke manifold, calibrated choke beans are used to control the flow rate through the fixed choke box. Each bean is a specific diameter, usually in graduations of one sixty-fourth of an inch, and is screwed into the choke box.
The tungsten carbide liner is what makes the bean last. Our grades of cemented carbide have been developed specifically to excel in aggressive environments that often include corrosive, abrasive and impacting elements at the same time.
The Common Sizes
These are the most common bean sizes in inches, depending on the type of equipment used:
1/8, 3/16, 1/4, 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, 3/4, 7/8, 1, 1-1/4 and 1-1/2.
Our published chart is finer than that list. It runs in single 1/64 inch steps from 3/64 inch through to 64/64 inch, which is item CH-03-5875 to CH-64-5875.
Reading The Item Number
The number in the middle is the bore in sixty-fourths of an inch.
| Bore inch | Sixty-fourths | Item no. | Bore mm | OD inch |
|---|---|---|---|---|
| 1/8 | 8/64 | CH-08-5875 | 3.175 | 0.375 |
| 3/16 | 12/64 | CH-12-5875 | 4.763 | 0.5 |
| 1/4 | 16/64 | CH-16-5875 | 6.350 | 0.5 |
| 5/16 | 20/64 | CH-20-5875 | 7.938 | 0.625 |
| 3/8 | 24/64 | CH-24-5875 | 9.525 | 0.625 |
| 7/16 | 28/64 | CH-28-5875 | 11.113 | 0.75 |
| 1/2 | 32/64 | CH-32-5875 | 12.700 | 0.75 |
| 9/16 | 36/64 | CH-36-5875 | 14.288 | 0.875 |
| 5/8 | 40/64 | CH-40-5875 | 15.875 | 0.875 |
| 3/4 | 48/64 | CH-48-5875 | 19.050 | 1 |
| 7/8 | 56/64 | CH-56-5875 | 22.225 | 1.125 |
| 1 | 64/64 | CH-64-5875 | 25.400 | 1.25 |
Bore sizes above one inch, including 1-1/4 and 1-1/2, are customizable rather than listed items.
Bore Alone Does Not Identify The Part
Outside diameter is grouped in bands. Bores from 3/64 to 8/64 inch sit in a 0.375 inch body, 9/64 to 16/64 in 0.5 inch, 17/64 to 24/64 in 0.625 inch, 25/64 to 32/64 in 0.75 inch, 33/64 to 40/64 in 0.875 inch, 41/64 to 48/64 in 1 inch, 49/64 to 56/64 in 1.125 inch and 57/64 to 64/64 in 1.25 inch. Outside diameter tolerance is +0 to −0.254 mm across the whole range, and the listed length is 149.225 mm with a ±0.381 mm tolerance.
Our liner is dimensioned to suit the choke bean of the Cameron type H2 Big John, where the body material is 410SS. For any other choke body, send the old bean or the box drawing.
Ordering A Graduated Set
Well test work usually needs a range rather than a single size. Order the range as one batch so every bean comes from the same grade and the same production lot, which means the wear behaviour is consistent as you step through the programme.
When To Change A Bean
Bleed down and confirm zero pressure before opening the choke box. Inspect the seat face inside the box as well as the bean itself: if the box has washed out, a new bean will not hold the setting either. Record the bore that went in, because a flow rate reading only means something against a known bore.
Frequently Asked Questions
What does 5875 mean in the item number?
It is part of the standard item code on our choke bean chart. The size information you need is the two digit number in the middle, which is the bore in sixty-fourths of an inch.
How long is a standard bean liner?
149.225 mm, with a tolerance of plus or minus 0.381 mm.
Which choke body do these fit?
They are dimensioned to suit the choke bean of the Cameron type H2 Big John, body material 410SS.
Can you make a bore that is not in the chart?
Yes, sizes are customizable. Send the bore, outside diameter, length and the choke body.
Still Not Sure
Send the drawing or describe the duty. Technical help with grade and preform design comes with the quotation, and quotes go out in 24 hours or less.