Horizontal well cluster perforation staged fracturing method

Abstract

The invention discloses a horizontal well cluster perforation staged fracturing method. The horizontal well cluster perforation staged fracturing method comprises the steps that the number of clusterof the first stage of the perforation is 2-4; the number of the cluster of other per stage perforation is set to be 6 or more; each cluster has four perforations, and the four perforation charges exhibit a 90-degree phase angle, so that the four perforations are located in the same plane in the direction perpendicular to a horizontal wellbore; and the diameter of the perforation is 14.5 mm or more. The horizontal well cluster perforation staged fracturing method increases the number of clusters in a single segment by optimizing the perforation position and parameters such as the number of perforations, the perforation diameter, the perforation density and the phase angle, and forms a single crack in the single cluster; and then the fracturing construction parameters are optimized and the pretreatment techniques such as medium-high-viscosity acid gradual extraction and displacement are combined, and the multi-cluster cracks in the segments are simultaneously cracked and extended. The technology can effectively increase the number of artificial cracks and crack length, improve the complexity of cracks, improve the transforming volume of cracks, solve the problem of the limitation ofthe current technology, and maximize the effect of a reservoir yield-increasing effect.

Description

technical field

[0001] The invention relates to the technical field of horizontal well fracturing, and more specifically relates to a horizontal well cluster perforation staged fracturing method. The invention can be used for segmental fracturing of horizontal wells in carbonate rock, sandstone, shale and other reservoirs. Background technique

[0002] At present, the application of staged fracturing technology for horizontal wells is becoming more and more common, such as sandstone, carbonate rock, shale and coalbed methane. And the casing completion ratio of horizontal wells is above 80%. However, the combination of cluster perforation and bridge plug is generally used for fracturing operations in casing-completed horizontal wells.

[0003] The cluster perforation in foreign countries generally adopts the spiral perforation mode, with multiple clusters in a single section, generally 3-8 clusters, and even more than 12 clusters. Generally, the cluster length is 0.3-0.6m, ...

Examples

Embodiment

[0078] In Well A, the lithology of the target interval is gray fluorescent fine sandstone with pebbles, and natural fractures are well developed. The fracturing section of the target layer is 3128.2-3589.7m, the average Young's modulus of the reservoir is 23.2GPa, and the average Poisson's ratio is 0.22; the stress difference between the target layer and the upper barrier is about 8MPa, and the stress difference between the target layer and the lower barrier is about 4MPa ; The target layer temperature is 112°C. In order to understand the gas-bearing property and production capacity of the target layer, and to carry out the next step of exploration and evaluation work in this block, the fracturing scheme design and on-site pilot of the well were carried out by referring to the process method proposed in this patent and combining with the actual situation of the well. The specific implementation method and effect of the test are as follows:

[0079] (1) Reservoir parameter eva...

technical field

[0001] The invention relates to the technical field of horizontal well fracturing, and more specifically relates to a horizontal well cluster perforation staged fracturing method. The invention can be used for segmental fracturing of horizontal wells in carbonate rock, sandstone, shale and other reservoirs. Background technique

[0002] At present, the application of staged fracturing technology for horizontal wells is becoming more and more common, such as sandstone, carbonate rock, shale and coalbed methane. And the casing completion ratio of horizontal wells is above 80%. However, the combination of cluster perforation and bridge plug is generally used for fracturing operations in casing-completed horizontal wells.

[0003] The cluster perforation in foreign countries generally adopts the spiral perforation mode, with multiple clusters in a single section, generally 3-8 clusters, and even more than 12 clusters. Generally, the cluster length is 0.3-0.6m, ...

Examples

Embodiment

[0078] In Well A, the lithology of the target interval is gray fluorescent fine sandstone with pebbles, and natural fractures are well developed. The fracturing section of the target layer is 3128.2-3589.7m, the average Young's modulus of the reservoir is 23.2GPa, and the average Poisson's ratio is 0.22; the stress difference between the target layer and the upper barrier is about 8MPa, and the stress difference between the target layer and the lower barrier is about 4MPa ; The target layer temperature is 112°C. In order to understand the gas-bearing property and production capacity of the target layer, and to carry out the next step of exploration and evaluation work in this block, the fracturing scheme design and on-site pilot of the well were carried out by referring to the process method proposed in this patent and combining with the actual situation of the well. The specific implementation method and effect of the test are as follows:

[0079] (1) Reservoir parameter eva...

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