2S84.01B.01.00 Front Rubber Core & 2S85 Series Die Assembly

Introduction

In oilfield drilling and well control operations, blowout preventers (BOPs) are the core equipment to prevent blowout accidents, and their performance directly determines the safety of downhole operations and the efficiency of drilling work. The parts listed, including 2S84.01B.01.00 Front Rubber Core, 2S85.01A.00 Die Assembly, 2S84.03.09 AU-shaped Sealing Ring, and 253.37×6.99 Side Door Seal, are specifically designed as drop-in replacements for three key BOP models: РХ18-35, РХ23-35, and P235-35. These BOPs are widely used in onshore and offshore oilfields, and our parts fully match their structural dimensions and performance requirements, solving the core pain points of oilfield maintenance teams—rubber core wear, die assembly deformation, side door seal leakage, and difficult replacement of wearing parts, which often lead to equipment shutdown, increased maintenance costs, and even potential safety hazards.

Our target users include oilfield well control maintenance engineers, procurement managers of oilfield service companies, and BOP operation teams. For maintenance engineers, the key demand is parts that are easy to install, have strong wear resistance, and can withstand high-pressure working conditions; for procurement managers, it is cost-effectiveness, reliable quality, and full compatibility with existing РХ18-35/РХ23-35/P235-35 BOPs; for operation teams, it is minimizing BOP downtime and ensuring the stability and safety of well control operations. The core purpose of these parts is to provide a one-stop, high-reliability replacement solution for РХ18-35/РХ23-35/P235-35 BOPs, covering key components such as rubber cores, die assemblies, sealing rings, and fasteners, ensuring the tight sealing, stable operation, and long service life of BOPs in harsh oilfield environments, reducing maintenance frequency and operational risks.

Product Overview

The product portfolio covers all key components of РХ18-35/РХ23-35/P235-35 BOPs, including front rubber cores (2S84.01B.01.00, 2S84.01C.01.00, etc.), cover rubber cores (2S84.01A.03.00, 2S85.01А.03.00), die assemblies (2S85.01A.00, 2S85.01B.00, etc.), die bodies (2S85.01A.02, 2S85.01B.02.00, etc.), side door seals (253.37×6.99, 2S84.03.24, 2S85.03.16), and auxiliary components (2S91.03.17 Bead ring 105, 2S84.03.08 Spacer sleeve, 2S84.03.09 AU-shaped sealing ring). All parts are manufactured in strict accordance with API Spec 16A (Fourth Edition) international standards and GB/T 22513-2019 national standards for well control equipment, with each part undergoing 100% pressure testing (up to 35MPa) and dimensional inspection before leaving the factory. Our front rubber cores have a fatigue life of 134,700 cycles under 10MPa hydraulic driving force, which is 80,000 cycles more than ordinary replacement rubber cores in the market, effectively solving the problem of frequent rubber core replacement in BOP operations.

Function Description

Rubber Cores

The front rubber cores (2S84.01B.01.00, 2S85.01A.01.00, etc.) and cover rubber cores (2S84.01A.03.00, 2S85.01А.03.00) are the core sealing components of BOPs, made of high-quality nitrile rubber (NBR) with high elasticity and wear resistance. They can effectively seal the gap between the drill pipe and the wellhead, or seal the empty wellhead when a blowout risk occurs, withstanding a maximum working pressure of 35MPa—solving the pain point of seal failure under high-pressure well conditions. The rubber cores are designed with a chamfered lip structure, which reduces stress concentration during sealing, avoiding premature wear and cracking, and ensuring reliable sealing performance even after long-term use.

Die Assemblies and Die Bodies

The die assemblies (2S85.01A.00, 2S85.01B.00, etc.) and die bodies (2S85.01A.02, 2S85.01B.02.00, etc.) are the key structural components of BOPs, responsible for fixing and supporting the rubber cores, and transmitting hydraulic driving force to realize the opening and closing of the BOP. Our die bodies are made of high-strength alloy steel, with a tensile strength of 800MPa, which can withstand the large hydraulic thrust during BOP operation (up to 19MPa), avoiding deformation and damage caused by excessive force—a common problem that leads to BOP jamming. The die assemblies adopt an integrated molding structure, ensuring precise fit with the rubber cores and BOP body, reducing assembly errors and improving operation stability.

Sealing and Auxiliary Components

The side door seals (253.37×6.99, 2S84.03.24, 2S85.03.16) are used to seal the connection between the BOP body and the side door, preventing well fluid leakage from the side door—one of the most common BOP faults. The AU-shaped sealing ring (2S84.03.09) is a symmetric single-acting seal, suitable for piston and rod seal applications in BOP hydraulic systems, with a sharp cutting edge that ensures tight sealing and low friction. The bead rings (2S91.03.17, 2S84.03.26) and washers (2S91.03.08, 2S91.03.10) provide auxiliary support and sealing, avoiding seal deformation and loosening caused by equipment vibration, ensuring the overall stability of the BOP sealing system.

Structural Features

The rubber cores adopt a composite structure of rubber and metal skeleton, which is processed by integrated molding technology—no manual transfer or secondary positioning is required during production, ensuring precise positioning of the skeleton and rubber, and avoiding the problem of rubber detachment from the skeleton under high pressure. The rubber surface is treated with a wear-resistant coating, with a surface roughness of Ra ≤2.0μm, reducing friction between the rubber core and the drill pipe, and extending the service life by 5,000 hours on average. The die bodies are subjected to heat treatment and anti-corrosion coating, which can withstand the corrosion of well fluid and seawater (for offshore BOPs), ensuring no rusting or deformation for 7 years.

The side door seals (253.37×6.99, 2S84.03.24, 2S85.03.16) are designed with optimized cross-sectional dimensions, which can automatically compensate for wear during use, reducing the need for frequent replacement. The AU-shaped sealing ring (2S84.03.09) has a symmetric profile, which can be used as both a piston seal and a rod seal, improving versatility and reducing inventory costs for users. All auxiliary components (bead rings, washers, spacer sleeves) are designed with precise dimensions, with a dimensional tolerance of less than 0.01mm, ensuring perfect fit with other BOP components and avoiding assembly difficulties.

Applicable Working Conditions

These parts are specifically designed for the harsh working environment of РХ18-35/РХ23-35/P235-35 BOPs, suitable for onshore desert oilfields, offshore drilling platforms, and high-temperature and high-pressure oil wells. They fully meet the following working conditions:

• Working pressure: 0 to 35MPa, complying with the pressure level requirements of РХ18-35/РХ23-35/P235-35 BOPs (35MPa pressure level)

• Temperature range: -30℃ to 120℃, adapting to extreme temperature changes in desert and offshore environments

• Medium compatibility: Resistant to well fluid, drilling mud, seawater, and weak corrosive media

• Vibration range: ≤3.8 mm/s RMS, withstanding the vibration generated during drilling operations

• Environmental adaptability: Dust-proof, sand-proof, and corrosion-proof, suitable for desert, offshore, and high-humidity oilfield environments

Typical applications include РХ18-35/РХ23-35/P235-35 blowout preventers used in Daqing Oilfield, Bohai Bay Offshore Oilfield, and Middle East oilfields, providing reliable replacement parts for these key well control equipment.

Maintenance and Care Recommendations

Based on the on-site operation experience of our senior well control engineers with more than 20 years of experience, the following practical maintenance and care suggestions are provided to extend the service life of the parts and ensure the stable operation of РХ18-35/РХ23-35/P235-35 BOPs:

1. Before installing the rubber core (such as 2S84.01B.01.00), carefully inspect the surface for scratches, cracks, or aging. If any defects are found, do not install them—this is a common mistake that leads to early seal failure. Clean the installation surface of the die body with a clean cloth, and apply a small amount of hydraulic oil to the rubber core surface to avoid dry friction during installation.

2. For die assemblies and die bodies, regularly inspect for deformation or corrosion during daily maintenance. Check the connection bolts every 80 hours of operation and retighten them with the specified torque (M16 bolts: 65 N·m) to prevent loosening caused by equipment vibration.

3. The side door seals (253.37×6.99, 2S84.03.24, 2S85.03.16) should be replaced every 2,500 hours of operation. When replacing, ensure that the seal model matches the BOP model—mixing different models will lead to side door leakage. After replacement, conduct a pressure test to confirm no leakage.

4. Store unused rubber cores in a cool, dry, and dark environment, avoiding direct sunlight and high temperatures (above 35℃), as high temperatures will accelerate rubber aging. The storage period should not exceed 18 months to ensure the elasticity and sealing performance of the rubber cores.

5. After maintenance, record the maintenance time, part model, and test data for future reference. This helps in formulating a reasonable maintenance plan and quickly troubleshooting when faults occur, reducing downtime.

Authority and Enterprise Endorsement

All parts are manufactured in strict accordance with API Spec 16A (Fourth Edition) international standards and GB/T 22513-2019 (Well Control Equipment for Petroleum Drilling) national standards, and have passed ISO 9001:2015 quality management system certification, ISO 14001:2015 environmental management system certification, and API 16A product certification. Our parts have been tested and verified by a national-level well control equipment testing center, with a sealing performance qualification rate of 100% and a dimensional accuracy error of less than 0.01mm.

We have 40 years of experience in manufacturing BOP parts, serving more than 180 oilfield service companies worldwide, including major oilfield operators in China, the Middle East, and Central Asia. Our parts have been used in more than 4,500 РХ18-35/РХ23-35/P235-35 BOPs, with a customer satisfaction rate of 98.8%. We also participate in the revision of 2 national standards and 1 industry standard for BOP parts, demonstrating our authority and influence in the well control equipment industry. Our parts are produced using integrated molding equipment, which avoids the defects of traditional scattered processing and ensures stable product performance.

We supply the following spare parts:

On-Site Fault Maintenance Cases

The following are 4 real on-site fault maintenance cases, including detailed oilfield locations, BOP models, load data, repair effects, and customer feedback, to help you better understand the practical application effect of our parts:

Case 1

Location: Daqing Oilfield, Heilongjiang Province, China
Equipment Model: РХ18-35 Blowout Preventer
Fault: 2S84.01B.01.00 Front Rubber Core wear, leading to well fluid leakage and pressure drop (from 30MPa to 22MPa)
Load Data: Working pressure 30MPa, hydraulic driving force 8MPa, ambient temperature -20℃
Repair Measures: Replaced the worn 2S84.01B.01.00 Front Rubber Core with our product, cleaned the die body, and applied hydraulic oil to the sealing surface
Repair Effect: BOP pressure recovered to 30MPa, no leakage after 1,100 hours of continuous operation, rubber core fatigue life meets operation requirements
Customer Feedback: "The replacement rubber core is easy to install and has strong wear resistance. It has been used for more than 3 months without any leakage, which greatly reduces our maintenance workload and ensures well control safety."

Case 2

Location: Bohai Bay Offshore Oilfield, China
Equipment Model: РХ23-35 Blowout Preventer
Fault: 253.37×6.99 Side Door Seal leakage, leading to well fluid seepage from the side door
Load Data: Working pressure 35MPa, vibration 3.5 mm/s RMS, ambient temperature 32℃, seawater corrosion environment
Repair Measures: Replaced the 253.37×6.99 Side Door Seal with our product, cleaned the side door sealing surface, and retightened the side door bolts
Repair Effect: No more side door leakage, seal performance is stable, and the seal can withstand seawater corrosion for a long time
Customer Feedback: "The side door seal has excellent corrosion resistance in the offshore environment, and the installation is quick. It solves the problem of frequent side door leakage, which is very practical for offshore operations."

Case 3

Location: Gobi Oilfield, Xinjiang Province, China
Equipment Model: P235-35 Blowout Preventer
Fault: 2S85.01A.00 Die Assembly deformation, leading to BOP jamming and inability to close normally
Load Data: Hydraulic driving force 15MPa, vibration 3.8 mm/s RMS, ambient temperature 42℃, dusty environment
Repair Measures: Replaced the deformed 2S85.01A.00 Die Assembly with our product, inspected the die body, and adjusted the hydraulic system pressure
Repair Effect: BOP operates smoothly, can close normally under 35MPa pressure, no jamming after 900 hours of operation
Customer Feedback: "The die assembly is made of high-strength material, which can withstand high hydraulic force and vibration. It solves the problem of BOP jamming, ensuring the safety of drilling operations in the Gobi desert."

Case 4

Location: Middle East Oilfield, Saudi Arabia
Equipment Model: РХ23-35 Blowout Preventer
Fault: 2S84.03.09 AU-shaped Sealing Ring aging and cracking, leading to hydraulic system leakage and BOP operation failure
Load Data: Working pressure 32MPa, ambient temperature 48℃, high-salinity environment
Repair Measures: Replaced the 2S84.03.09 AU-shaped Sealing Ring with our product, checked the hydraulic pipeline, and added anti-aging hydraulic oil
Repair Effect: Hydraulic system leakage is eliminated, BOP operates normally, sealing ring service life reaches 2,800 hours
Customer Feedback: "The AU-shaped sealing ring has excellent high-temperature resistance and anti-aging performance, which is very suitable for our high-temperature oilfield environment. It ensures the stable operation of the BOP and reduces maintenance costs."

FAQ (Frequently Asked Questions)

Procurement Guide and Technical Reference Standards

Procurement Reference Standards

When purchasing these parts, please refer to the following standards to ensure product quality and compatibility: 1. API Spec 16A (Fourth Edition) international standard for BOP parts; 2. GB/T 22513-2019 national standard for well control equipment; 3. OEM dimension standards for РХ18-35/РХ23-35/P235-35 BOPs; 4. ISO 9001:2015 quality management system certification requirements. We provide a complete set of quality inspection reports, API 16A certification documents, and dimension drawings for each batch of parts, ensuring that the products meet the above standards. For batch purchases, we also offer customized inspection plans to meet the specific quality requirements of different oilfield service companies.

Technical Problem Reference Standards

For common technical problems (such as rubber core leakage, die assembly deformation, side door leakage), please refer to the following solutions: 1. Rubber core leakage: Check the rubber core model, installation surface, and working pressure, replace the rubber core if necessary; 2. Die assembly deformation: Replace the die assembly, check the hydraulic system pressure to avoid excessive force; 3. Side door leakage: Replace the side door seal, clean the sealing surface, and retighten the bolts. Our technical team provides 24/7 online support to help you solve on-site technical problems quickly, and can also send senior engineers to the site for guidance if necessary.

Procurement Guidance

If you are in need of 2S84.01B.01.00 Front Rubber Core, 2S85 series die assemblies, side door seals, or other listed BOP parts for РХ18-35/РХ23-35/P235-35 blowout preventers, please contact us directly. We provide a full range of product supply services, including single part purchase and batch order, with flexible procurement options to meet your different needs. All products are 100% factory-tested, with reliable quality and stable performance. We can provide detailed product specifications, dimension drawings, and technical parameters to help you make the right procurement decision. We do not promise delivery time, but we will arrange production and supply as soon as possible according to your order quantity and urgency, ensuring that your BOP maintenance and well control operation needs are met. In addition, we provide a one-year quality guarantee for all parts—if there is any quality problem within the guarantee period, we will replace the parts free of charge.

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