diff --git a/src/alfasim_score/constants.py b/src/alfasim_score/constants.py
index a83b5ad..fca8d95 100644
--- a/src/alfasim_score/constants.py
+++ b/src/alfasim_score/constants.py
@@ -1,10 +1,13 @@
 from barril.units import Scalar
 
 from alfasim_score.units import DENSITY_UNIT
+from alfasim_score.units import DIAMETER_UNIT
+from alfasim_score.units import DIMENSIONLESS
 from alfasim_score.units import FRACTION_UNIT
 from alfasim_score.units import HEAT_TRANSFER_COEFFICIENT_UNIT
 from alfasim_score.units import LENGTH_UNIT
 from alfasim_score.units import MASS_FLOW_RATE_UNIT
+from alfasim_score.units import PRESSURE_UNIT
 from alfasim_score.units import ROUGHNESS_UNIT
 from alfasim_score.units import STD_VOLUMETRIC_FLOW_RATE_UNIT
 
@@ -14,6 +17,7 @@
 ANNULUS_TOP_NODE_NAME = "WELLBORE_ANNULUS_TOP_NODE"
 GAS_LIFT_MASS_NODE_NAME = "GAS_LIFT_MASS_NODE"
 CEMENT_NAME = "cement"
+GAS_LIFT_VALVE_NAME = "GAS_LIFT_VALVE"
 
 ROCK_DEFAULT_ROUGHNESS = Scalar(0.1, ROUGHNESS_UNIT)
 ROCK_DEFAULT_HEAT_TRANSFER_COEFFICIENT = Scalar(1000.0, HEAT_TRANSFER_COEFFICIENT_UNIT)
@@ -22,7 +26,7 @@
 
 REFERENCE_VERTICAL_COORDINATE = Scalar(0.0, LENGTH_UNIT, "length")
 
-# This default fluid name for packer and fluid above filler
+# this default fluid name for packer and fluid above filler
 FLUID_DEFAULT_NAME = "fluid_default"
 
 # nodes data
@@ -37,3 +41,8 @@
 # default values used in the context of black-oil models
 H2S_MOLAR_FRACTION_DEFAULT = Scalar(0.0, FRACTION_UNIT)
 CO2_MOLAR_FRACTION_DEFAULT = Scalar(0.0, FRACTION_UNIT)
+
+# gas lift default values
+GAS_LIFT_VALVE_DEFAULT_DIAMETER = Scalar(0.25, DIAMETER_UNIT, "diameter")
+GAS_LIFT_VALVE_DEFAULT_DISCHARGE = Scalar(0.826, DIMENSIONLESS)
+GAS_LIFT_VALVE_DEFAULT_DELTA_P_MIN = Scalar(0.0, PRESSURE_UNIT)
diff --git a/src/alfasim_score/converter/alfacase/_tests/test_convert_alfacase/test_create_alfacase.alfacase b/src/alfasim_score/converter/alfacase/_tests/test_convert_alfacase/test_create_alfacase.alfacase
index a660420..8f01b46 100644
--- a/src/alfasim_score/converter/alfacase/_tests/test_convert_alfacase/test_create_alfacase.alfacase
+++ b/src/alfasim_score/converter/alfacase/_tests/test_convert_alfacase/test_create_alfacase.alfacase
@@ -954,7 +954,7 @@ wells:
             values:
             - 288.6
             unit: K
-    top_node: WELLBORE_ANNULUS_TOP_NODE
+    top_node: GAS_LIFT_MASS_NODE
   formation:
     reference_y_coordinate:
       value: 0.0
diff --git a/src/alfasim_score/converter/alfacase/_tests/test_convert_alfacase/test_create_alfacase_with_operation.alfacase b/src/alfasim_score/converter/alfacase/_tests/test_convert_alfacase/test_create_alfacase_with_operation.alfacase
index 99dfe9b..f189c43 100644
--- a/src/alfasim_score/converter/alfacase/_tests/test_convert_alfacase/test_create_alfacase_with_operation.alfacase
+++ b/src/alfasim_score/converter/alfacase/_tests/test_convert_alfacase/test_create_alfacase_with_operation.alfacase
@@ -126,7 +126,7 @@ pipes: []
 nodes:
 - name: WELLBORE_TOP_NODE
   node_type: mass_source_boundary
-  pvt_model: base
+  pvt_model: DFLT_BLACK_OIL_27.40_230.00_1.17
   pressure_properties:
     pressure:
       value: 100000.0
@@ -217,7 +217,7 @@ nodes:
       max_rate_of_change: 1e+50
 - name: WELLBORE_BOTTOM_NODE
   node_type: pressure_boundary
-  pvt_model: base
+  pvt_model: DFLT_BLACK_OIL_27.40_230.00_1.17
   pressure_properties:
     pressure:
       value: 9814.11
@@ -298,7 +298,7 @@ nodes:
       max_rate_of_change: 1e+50
 - name: GAS_LIFT_MASS_NODE
   node_type: mass_source_boundary
-  pvt_model: gas_lift
+  pvt_model: DFLT_BLACK_OIL_27.40_230.00_1.17
   pressure_properties:
     pressure:
       value: 100000.0
@@ -389,7 +389,7 @@ nodes:
       max_rate_of_change: 1e+50
 wells:
 - name: WELLBORE
-  pvt_model: base
+  pvt_model: DFLT_BLACK_OIL_27.40_230.00_1.17
   stagnant_fluid: fluid_default
   profile:
     x_and_y:
@@ -803,7 +803,8 @@ wells:
         value: 0.1
         unit: mm
   annulus:
-    has_annulus_flow: False
+    has_annulus_flow: True
+    pvt_model: DFLT_BLACK_OIL_27.40_230.00_1.17
     initial_conditions:
       pressures:
         position_input_type: length
@@ -954,7 +955,23 @@ wells:
             values:
             - 288.6
             unit: K
-    top_node: WELLBORE_ANNULUS_TOP_NODE
+    equipment:
+      gas_lift_valves:
+        GAS_LIFT_VALVE_1:
+          position:
+            value: 928.0
+            unit: m
+          diameter:
+            value: 0.25
+            unit: in
+          valve_type: check_valve
+          delta_p_min:
+            value: 0.0
+            unit: psi
+          discharge_coefficient:
+            value: 0.826
+            unit: unitless
+    top_node: GAS_LIFT_MASS_NODE
   formation:
     reference_y_coordinate:
       value: 0.0
diff --git a/src/alfasim_score/converter/alfacase/base_operation.py b/src/alfasim_score/converter/alfacase/base_operation.py
index 269ccef..d2bb42a 100644
--- a/src/alfasim_score/converter/alfacase/base_operation.py
+++ b/src/alfasim_score/converter/alfacase/base_operation.py
@@ -1,17 +1,36 @@
+from typing import Dict
 from typing import List
 
 import attr
+from alfasim_sdk import AnnulusDescription
+from alfasim_sdk import AnnulusEquipmentDescription
+from alfasim_sdk import GasLiftValveEquipmentDescription
+from alfasim_sdk import InitialConditionsDescription
+from alfasim_sdk import InitialPressuresDescription
+from alfasim_sdk import InitialTemperaturesDescription
+from alfasim_sdk import InitialVelocitiesDescription
+from alfasim_sdk import InitialVolumeFractionsDescription
 from alfasim_sdk import MassInflowSplitType
 from alfasim_sdk import MassSourceNodePropertiesDescription
 from alfasim_sdk import MassSourceType
 from alfasim_sdk import MultiInputType
 from alfasim_sdk import NodeDescription
+from alfasim_sdk import PressureContainerDescription
 from alfasim_sdk import PressureNodePropertiesDescription
+from alfasim_sdk import TableInputType
+from alfasim_sdk import ValveType
+from alfasim_sdk import WellDescription
 from alfasim_sdk._internal.constants import FLUID_GAS
 from alfasim_sdk._internal.constants import FLUID_OIL
 from alfasim_sdk._internal.constants import FLUID_WATER
 
+from alfasim_score.common import LiftMethod
+from alfasim_score.common import ModelFluidType
 from alfasim_score.constants import GAS_LIFT_MASS_NODE_NAME
+from alfasim_score.constants import GAS_LIFT_VALVE_DEFAULT_DELTA_P_MIN
+from alfasim_score.constants import GAS_LIFT_VALVE_DEFAULT_DIAMETER
+from alfasim_score.constants import GAS_LIFT_VALVE_DEFAULT_DISCHARGE
+from alfasim_score.constants import GAS_LIFT_VALVE_NAME
 from alfasim_score.constants import NULL_VOLUMETRIC_FLOW_RATE
 from alfasim_score.constants import WELLBORE_BOTTOM_NODE_NAME
 from alfasim_score.constants import WELLBORE_TOP_NODE_NAME
@@ -23,7 +42,37 @@ class BaseOperationBuilder(ScoreAlfacaseConverter):
     def __init__(self, score_reader: ScoreInputReader):
         super().__init__(score_reader)
 
+    def has_gas_lift(self) -> bool:
+        """Check the operation has gas lift."""
+        return self.score_input.read_operation_data()["lift_method"] == LiftMethod.GAS_LIFT
+
+    def _get_gas_lift_valves(self) -> Dict[str, GasLiftValveEquipmentDescription]:
+        """Create the gas lift valves for the annulus."""
+        gas_lift_data = self.score_input.read_operation_method_data()
+        valves = {
+            f"{GAS_LIFT_VALVE_NAME}_1": GasLiftValveEquipmentDescription(
+                position=self._get_position_in_well(gas_lift_data["valve_depth"]),
+                diameter=GAS_LIFT_VALVE_DEFAULT_DIAMETER,
+                valve_type=ValveType.CheckValve,
+                delta_p_min=GAS_LIFT_VALVE_DEFAULT_DELTA_P_MIN,
+                discharge_coefficient=GAS_LIFT_VALVE_DEFAULT_DISCHARGE,
+            )
+        }
+        return valves
+
+    def build_annulus(self) -> AnnulusDescription:
+        """Configure the annulus with data from SCORE operation."""
+        return AnnulusDescription(
+            has_annulus_flow=self.has_gas_lift(),
+            pvt_model=self.get_fluid_model_name(),
+            equipment=AnnulusEquipmentDescription(
+                gas_lift_valves=self._get_gas_lift_valves(),
+            ),
+            top_node=GAS_LIFT_MASS_NODE_NAME,
+        )
+
     def build_nodes(self) -> List[NodeDescription]:
+        """ "Configure the nodes with data from SCORE operation."""
         operation_data = self.score_input.read_operation_data()
         default_nodes = {node.name: node for node in super().build_nodes()}
         configured_nodes = [
@@ -40,6 +89,7 @@ def build_nodes(self) -> List[NodeDescription]:
                         FLUID_WATER: -1.0 * operation_data["water_flow_rate"],
                     },
                 ),
+                pvt_model=self.get_fluid_model_name(),
             ),
             attr.evolve(
                 default_nodes.pop(WELLBORE_BOTTOM_NODE_NAME),
@@ -48,9 +98,10 @@ def build_nodes(self) -> List[NodeDescription]:
                     pressure=operation_data["flow_initial_pressure"],
                     split_type=MassInflowSplitType.Pvt,
                 ),
+                pvt_model=self.get_fluid_model_name(),
             ),
         ]
-        if GAS_LIFT_MASS_NODE_NAME in default_nodes:
+        if self.has_gas_lift():
             gas_lift_data = self.score_input.read_operation_method_data()
             configured_nodes.append(
                 attr.evolve(
@@ -65,6 +116,14 @@ def build_nodes(self) -> List[NodeDescription]:
                             FLUID_WATER: NULL_VOLUMETRIC_FLOW_RATE,
                         },
                     ),
+                    pvt_model=self.get_fluid_model_name(),
                 )
             )
         return configured_nodes
+
+    def build_well(self) -> WellDescription:
+        """Create the description for the well."""
+        return attr.evolve(
+            super().build_well(),
+            pvt_model=self.get_fluid_model_name(),
+        )
diff --git a/src/alfasim_score/converter/alfacase/convert_alfacase.py b/src/alfasim_score/converter/alfacase/convert_alfacase.py
index f3bdd7d..66d2fc1 100644
--- a/src/alfasim_score/converter/alfacase/convert_alfacase.py
+++ b/src/alfasim_score/converter/alfacase/convert_alfacase.py
@@ -35,11 +35,10 @@
 from alfasim_sdk._internal.constants import FLUID_WATER
 from barril.units import Scalar
 
-from alfasim_score.common import LiftMethod
+from alfasim_score.common import ModelFluidType
 from alfasim_score.common import convert_api_gravity_to_oil_density
 from alfasim_score.common import convert_gas_gravity_to_gas_density
 from alfasim_score.common import convert_quota_to_tvd
-from alfasim_score.constants import ANNULUS_TOP_NODE_NAME
 from alfasim_score.constants import BASE_PVT_TABLE_NAME
 from alfasim_score.constants import CASING_DEFAULT_ROUGHNESS
 from alfasim_score.constants import CEMENT_NAME
@@ -58,6 +57,7 @@
 from alfasim_score.constants import WELLBORE_TOP_NODE_NAME
 from alfasim_score.converter.alfacase.score_input_reader import ScoreInputReader
 from alfasim_score.units import LENGTH_UNIT
+from alfasim_score.units import PRESSURE_UNIT
 from alfasim_score.units import TEMPERATURE_UNIT
 
 
@@ -90,6 +90,10 @@ def _get_position_in_well(self, position: Scalar) -> Scalar:
         """Get the position relative to the well start position."""
         return position - self.well_start_position
 
+    def get_fluid_model_name(self) -> ModelFluidType:
+        """Get the name of the fluid model used for this operation."""
+        return self.score_input.read_operation_fluid_data()["name"]
+
     def _convert_well_trajectory(self) -> ProfileDescription:
         """
         Convert the trajectory for the imported well.
@@ -123,11 +127,9 @@ def _convert_materials(self) -> List[MaterialDescription]:
             )
         return filter_duplicated_materials(material_descriptions)
 
-    def _convert_annulus(self) -> AnnulusDescription:
-        # TODO PWPA-1937: implement this method
-        # TODO PWPA-1937: Use the GAS_LIFT_MASS_NODE, check for the gas lift presence
-        #                 and set flow rate zero with the flag false for annulus flow.
-        return AnnulusDescription(has_annulus_flow=False, top_node=ANNULUS_TOP_NODE_NAME)
+    def build_annulus(self) -> AnnulusDescription:
+        """Create the description for the annulus."""
+        return AnnulusDescription(has_annulus_flow=False, top_node=GAS_LIFT_MASS_NODE_NAME)
 
     def _convert_formation(self) -> FormationDescription:
         """Create the description for the formations."""
@@ -305,25 +307,21 @@ def build_nodes(self) -> List[NodeDescription]:
                     split_type=MassInflowSplitType.Pvt,
                 ),
             ),
+            NodeDescription(
+                name=GAS_LIFT_MASS_NODE_NAME,
+                node_type=NodeCellType.MassSource,
+                pvt_model=GAS_LIFT_PVT_TABLE_NAME,
+                mass_source_properties=MassSourceNodePropertiesDescription(
+                    temperature_input_type=MultiInputType.Constant,
+                    source_type=MassSourceType.AllVolumetricFlowRates,
+                    volumetric_flow_rates_std={
+                        FLUID_GAS: NULL_VOLUMETRIC_FLOW_RATE,
+                        FLUID_OIL: NULL_VOLUMETRIC_FLOW_RATE,
+                        FLUID_WATER: NULL_VOLUMETRIC_FLOW_RATE,
+                    },
+                ),
+            ),
         ]
-        operation_input_data = self.score_input.read_operation_data()
-        if operation_input_data["lift_method"] == LiftMethod.GAS_LIFT:
-            nodes.append(
-                NodeDescription(
-                    name=GAS_LIFT_MASS_NODE_NAME,
-                    node_type=NodeCellType.MassSource,
-                    pvt_model=GAS_LIFT_PVT_TABLE_NAME,
-                    mass_source_properties=MassSourceNodePropertiesDescription(
-                        temperature_input_type=MultiInputType.Constant,
-                        source_type=MassSourceType.AllVolumetricFlowRates,
-                        volumetric_flow_rates_std={
-                            "gas": NULL_VOLUMETRIC_FLOW_RATE,
-                            "oil": NULL_VOLUMETRIC_FLOW_RATE,
-                            "water": NULL_VOLUMETRIC_FLOW_RATE,
-                        },
-                    ),
-                )
-            )
         return nodes
 
     def build_well(self) -> WellDescription:
@@ -334,7 +332,7 @@ def build_well(self) -> WellDescription:
             stagnant_fluid=FLUID_DEFAULT_NAME,
             profile=self._convert_well_trajectory(),
             casing=self._convert_casings(),
-            annulus=self._convert_annulus(),
+            annulus=self.build_annulus(),
             formation=self._convert_formation(),
             top_node=WELLBORE_TOP_NODE_NAME,
             bottom_node=WELLBORE_BOTTOM_NODE_NAME,
@@ -342,7 +340,7 @@ def build_well(self) -> WellDescription:
         )
 
     def build_case_description(self) -> CaseDescription:
-        """ "Create the description for the alfacase."""
+        """Create the description for the alfacase."""
         return CaseDescription(
             name=self.general_data["case_name"],
             physics=self.build_physics(),
diff --git a/src/alfasim_score/units.py b/src/alfasim_score/units.py
index 59f9d56..9e9c081 100644
--- a/src/alfasim_score/units.py
+++ b/src/alfasim_score/units.py
@@ -14,3 +14,4 @@
 TEMPERATURE_UNIT = "degC"
 GAS_OIL_RATIO_UNIT = "sm3/sm3"
 HEAT_TRANSFER_COEFFICIENT_UNIT = "W/m2.K"
+DIMENSIONLESS = "unitless"