Flowline
Choke beans, seats and stems
The orifice in a choke takes the full pressure drop and every grain of sand in the flow. Beans, seats and stem tips are the parts that wear, and the parts most worth making in the right material.
A choke bean is the replaceable orifice insert in a positive choke; in an adjustable choke the same job is done by a seat and a tapered stem tip. Orifice sizes are given in 64ths of an inch, so a 32/64 bean has a 1/2 in orifice. We make beans, seats and stems to fit your choke bodies, in alloy or stainless steel for clean fluids and with tungsten carbide or ceramic linings where sand and high pressure drops would cut steel quickly.
Orifice sizes
| Size | Orifice, in | Orifice, mm |
|---|---|---|
| 8/64 | 0.125 | 3.2 |
| 12/64 | 0.188 | 4.8 |
| 16/64 | 0.250 | 6.3 |
| 20/64 | 0.313 | 7.9 |
| 24/64 | 0.375 | 9.5 |
| 32/64 | 0.500 | 12.7 |
| 40/64 | 0.625 | 15.9 |
| 48/64 | 0.750 | 19.0 |
| 64/64 | 1.000 | 25.4 |
Any size in 64ths can be made, up to the largest bean the choke body accepts.
Trim materials
| Material | Strength | Use it for |
|---|---|---|
| Alloy or stainless steel | Tough and low cost, but erodes fastest | Clean liquids and gas, short jobs |
| Tungsten carbide lined | Very hard and tough; tolerates surges | Sandy flowback, cleanup and test flows |
| Ceramic lined | Very hard and erosion resistant; more brittle | Erosive or corrosive flow without heavy impact |
Lined beans have a steel body carrying the threads and a hard insert forming the orifice, so the insert takes the wear and the body takes the make-up torque. Adjustable choke trim follows the same rule: a hard stem tip working against a hard seat.
Positive beans and adjustable trim
A positive bean screws into the choke body and is changed to change the rate; the size is stamped on its head so it can be read before it goes in. In an adjustable choke, the handwheel moves the stem towards the seat to close the opening, and the indicator reads in 64ths. Worn stem tips and seats make the indicator lie, because the true opening grows as the trim erodes, so they are replaced on a schedule or when the rate stops matching the reading.
Beans are not interchangeable between makes. Thread, outside diameter, length and seating face must match the body. Send the make and model, a used bean or a drawing with each order.
Ordering
Positive choke bean, tungsten carbide lined, 24/64 in orifice, to fit the 2 in positive choke body in the attached drawing, 10 pcs; 32/64 in, 10 pcs
Adjustable choke trim, tungsten carbide stem tip and seat, 1 in maximum orifice, to fit the 2 in adjustable choke in the attached drawing, 4 sets
Frequently asked questions
What does a 24/64 choke mean?
An orifice of 24/64 in, which is 3/8 in or 0.375 in (9.5 mm) across. Choke sizes are always given in 64ths of an inch, so a 64/64 choke is a 1 in orifice.
Tungsten carbide or ceramic?
Both resist sand far better than steel. Tungsten carbide is tougher and takes knocks and pressure surges better; ceramic resists erosion and many corrosive fluids very well but is more brittle. For sandy flowback, tungsten carbide is the usual choice.
Will your beans fit our choke bodies?
They are made to fit the body they go into: send the body make and model, a used bean or a drawing with the thread, outside diameter and length, and we make the bean to it.
Do you keep beans in stock?
No. Beans are made to your order and your body, in the sizes and materials on your list. Small mixed orders are welcome.