Turning downtime to uptime: Enhancing Drill Pipe Float Valve design for an International Oilfield Service Company
Client: Major international well service company
Industry: Upstream Oil & Gas
Location: Saudi Arabia
Introduction
In 2016, IRE was contacted by a leading well service company based in Saudi Arabia to open a discussion on supplying Float Valves. Our Partner, Keystone Energy Tools, is a leading manufacturer of Float Valves so we brought them into the discussion to identify what challenges our client was facing and how we could prevent those issues. This case study outlines the collaborative efforts between IRE, Keystone and the client to improve the design, quality and reliability of these critical components.
Challenges
The client was experiencing frequent and severe failures with their existing flapper valves, which resulted in an operational failure rate exceeding 50%. This resulted in pressure from the NOC to improve results or face contract termination.
The primary challenge was the recurring failure of the valve springs in less than two days of operation. This high failure rate caused the flapper valves to remain open downhole, leading to lost time and increased costs. As a result, the client began sourcing another brand in the market to test their performance – that’s when they contacted IRE.
Assessing our client’s requirements
To gain a full understanding of the challenges and contributing factors at play, IRE initiated discussions with the client and Keystone. The client provided detailed data reports on run times and post-operation inspections, which offered critical insights into wear patterns and failure points of the valves. Frequent failures were identified with the existing flapper valves highlighting three major areas for improvement:
- Strength of valve springs
- Poor seal quality and swelled hinges
- Integrity of the valve body
Over a two year period, IRE and Keystone engaged in a rigorous iterative process analysing failed valves to refine the float valve design. Consistent wear and fatigue were highlighted at two specific contact points between the spring and the pin. Although the dimensions and manufacturing tolerances were within acceptable limits, it became evident that the existing spring design could not withstand the operational stresses encountered during use.
Solution assessment and qualification
To address these challenges, IRE and Keystone began root cause analysis then developed a corrective and preventative action plan which involved designing several new prototypes. The client agreed to test these in-field and report back findings for further review and improvements.
Keystone made several design changes including the spring material, spring sizing, seal material and valve body constructions (going from cast to machined). After new designs were manufactured and tested by Keystone, IRE sent over 15 samples of the new prototypes to the client for further testing. Throughout the trial, the company meticulously recorded key data relating to the valves, springs, operational hours and relevant mud data.
After the operational period, the client inspected and photographed the valves, sharing the collected data with IRE and Keystone for joint evaluation. IRE regularly visited Saudi Arabia on behalf of Keystone to inspect the tested prototype valves and gather feedback directly from the field – a crucial step in fine-tuning the design to meet the demands of drilling.
Design Improvements
Looking at the spring design in isolation, Keystone’s engineering team increased wire diameter by 30% to increase spring strength and added a new coating to further reduce washout allowing for further re-runs. These changes combined increased tension and load capacity by 600%. The enhancements allowed tension to be dispersed among all coils to reduce stress at specific points to boost durability.
Keystone refined the manufacturing process by continuing to use an investment casting method for the float valve body but machined the ID to size to ensure a smoother and more precise finish compared to the previous process. To enhance durability for use in harsh environments, a prototype valve body was developed with a nickel coating to reduce washout, erosion and overall elevate the valve’s resistance to corrosive environments.
Furthermore, Keystone also developed a new prototype designed specifically to address the client’s need for double stacking two float valves inside the sub body. With guidance from the client, Keystone designed a new single-body, double-valve design for the client to test. This helped to reduce the cost, shortened the length of a double valve assembly and saved time during changeout and redressing.
Deliverables and Results
The outcome of the collaborative project was highly positive. The upgraded valves improved performance, with the new design ensuring a longer operational life, a notable reduction in failure rates and significant cost savings. As a result, the NOC was highly satisfied with the reliability of the equipment in service which was a key factor in contributing to multiple contract extensions for our client.
Based on these successful trials, IRE and Keystone proceeded to supply upgraded springs, seals and cages on all new float valves going to the client. This case study highlights several key insights. It underscores the importance of robust design enhancements and careful material selection to ensure durability in harsh operational conditions. Secondly, it demonstrates the effectiveness of collaborative problem-solving, where joint efforts between the manufacturer and the client can address and resolve critical issues.
Most significantly, it emphasises the value of data-driven decisions, where detailed recording and analysis of operational data are essential for validating improvements.
Since the finalisation of the valve design in 2018, the client has continued to support and utilise the new float valves without any reported complaints or failures.
Through meticulous investigation, innovative design enhancements and comprehensive testing, this collaboration significantly improved the performance and reliability of the valves. This led to better operational outcomes which further spotlight the advantages of collaborative problem-solving and cutting-edge engineering solutions.
This partnership not only improved the quality and reliability of the equipment but also reinforced our client’s reputation with the NOC and provided a competitive advantage in the demanding oil and gas sector.
