# **Comprehensive Analysis of Pressure-Resistant Sealing Equipment: A Complete Installation Guide from Basic Tools to Professional Systems** ## **Introduction** The pressure-sealing technology, as the core process of modern pipeline maintenance and repair, can complete pipeline repair, renovation and branch operations without pipeline shutdown. It is widely applied in high-pressure pipeline systems such as those for oil, gas and chemicals. According to statistics, standardized pressure-sealing operations can reduce pipeline shutdown losses by over 90%, but the operation risk coefficient is 3-5 times that of conventional maintenance. This article will systematically introduce the professional equipment system required for pressure-sealing operations, covering key systems such as mechanical sealing, hydraulic control and safety monitoring, and provide equipment selection guidelines and operation specifications to help engineering teams complete the operations safely and efficiently. ## 1. Classification and Equipment Differences of Pressure-Resistant Sealing Technology 1.1 Comparison of Three Main Blocking Processes | **Type** | **Applicable Pressure** | **Core Equipment** | **Typical Applications** | |---------|------------|------------|------------|| **Capsule Sealing** | ≤1.6MPa | Expansion sealing capsule, injection pump | Low-pressure gas pipeline | | **Mechanical Clamping Type** | ≤10MPa | Double-sealing double-blocking machine, balance valve assembly | Long-distance crude oil pipeline | | **Foldable Sealing** | ≤ 4.0 MPa | Foldable sealing head, hydraulic station | Chemical medium pipeline | 1.2 Requirements for Equipment Based on Pressure Levels - **Low pressure (less than 1.6 MPa)**: Manual hydraulic pumps and simple fixtures can be used. - **Medium pressure (1.6 - 4.0 MPa)**: A dual-channel hydraulic system must be equipped. - **High pressure (＞4.0 MPa)**: Requires explosion-proof electro-hydraulic control system ## 2. List of Basic Operating Equipment ### 2.1 Core Blocking Unit #### (1) Blockage of the three-way valve device - **Composition**: Welded/Clamp-type three-way fitting, sealing bushing - **Selection Guidelines**: ✓ Material matches pipeline steel grade (special heat treatment required for X60 - X80) ✓ The deviation of the path is less than 0.5% of the pipe diameter (D represents the diameter of the pipe) #### (2) Blocking the actuator - **Mechanical type** Chain-type plug (DN200 - DN600) Gear and rack type (DN600 and above) - **Hydraulic type** Double-acting hydraulic cylinder (stroke should be ≥ 1.5 times the pipe diameter) ### 2.2 Pressure Control System | **Equipment** | **Functional Requirements** | **Safety Standards** | |---------|------------|------------|| Hydraulic Power Station | Flow rate ≥ 20L/min, Pressure 35MPa | Equipped with relief valve and pressure memory function | | Balance Discharge System | Dual-valve group structure, response time < 3 seconds | API 6D certified | | Pressure Monitoring Unit | Digital display with ±0.5% accuracy | Explosion-proof rating ExdⅡBT4 | ## III. Detailed Explanation of Professional Supporting Equipment ### 3.1 Pipeline Pre-treatment Equipment #### (1) Hole Punching System - **Combination Type Hole Puncher** ✓ The radial runout of the spindle is less than 0.03mm ✓ Equipped with quick-change tool holder (suitable for carbon steel / stainless steel) - **Key Parameters** The maximum cutting torque is ≥ 3000 N·m (for DN1000 pipes) The feed speed can be adjusted from 0.1 to 2 mm per second. #### (2) Weld Seam Inspection Equipment