AlfaSlot
Description
AlfaSlot is and one of the simplest options for a slotted sand screen. Slotted holes are mechanically cut in the base pipe. Filters are manufactured on a special machine with a set of saws for cutting slits or slots in the base pipe. The slot width varies from 0.3 mm to 4-6 mm.
The productivity of the machine depends on the size of the slot; the time for cutting the slots increases with decreasing the width of the slot. The slots are rectangular. Longitudinal cutting of slots is used. The slicing pattern may include double or quadruple slots, staggered or otherwise evenly distributed throughout the pipe.
The use of a multiple slot cutting template allows a multiple increase of the open filter surface area. The error in the width of the slot depends on its size, the smaller the size, the smaller the error. On average, it is +/-50 microns. The quality of the slots cutting is checked, the treated surface is cleaned of all kinds of mechanical burrs, if necessary, it can be treated with a special lubricant or wax to prevent rust before installing the filter in the well. In the production of slotted filters, it is possible to use pipes of different materials standards, pipe diameters can vary from 1.5 to 18 inches.
Slotted filters are used to equip producing oil horizontal wells in a wide range of conditions. Filters of this type are easy to use and install. Despite the small open surface, slot filters are quite effective for long horizontal wells. When running a liner with slotted filters, as well as their operation, their strength to different loads is important: compression, bending, torsion, longitudinal tension-compression, thermal stress. The design of the slotted holes is designed in such a way that the product has sufficient resistance to these loads, comparable to the strength of a conventional or perforated pipe. The resistance of the filter to torsional loads is of key importance in the technological running of the string into the well, since the running is performed with rotation and the filters must withstand these loads without deforming the slot holes.
AlfaSlot is used to equip producing oil horizontal wells in a wide range of conditions.
AlfaSlot filters are easy to use and install, and despite the small open surface, they are quite effective for long horizontal wells. AlfaSlot solution is an economical alternative to wire filters for sand control, but with less erosion resistance.
Characteristics
- High strength to torsional, longitudinal compression, bending, compression loads
- Slot width 0.3 - 6 mm, length 50-70 mm, pitch 75-100 mm
- Rectangular slit shape, template can include double, quadruple slots and different layout options
- Filter pipes can be sized from 1.5 to 18 inches
- Small open section area 1-4%.
- Slit width accuracy, ± 50 microns
- The ability to equalize the inflow by changing the density of slot holes along the well
Usage
Slot screens are used in a wide range of oil production conditions. Slotted screens are mainly used for long horizontal poduction oil wells or injection wells and SAGD wells
Advantages
- The slotted screen provides a stable inflow of the produced fluid with sand filtration according to the size of the filter slots.
- Slotted screen allows efficient running of liners over long horizontal distances using a rotating set-up.
- Slotted screens are a simple and reliable solution with a high structural strength.
- The slots design and their distribution along the well allows you to effectively solve the issues of uniform inflow.
- AlfaSlot is a cost – effective solution, prices are lower than other sand screen types
Scheme of the device
