Use of hazardous event frequency to evaluate safety integrity level of subsea blowout preventer

The Distributed Electro-hydraulic Braking system (DEHB) is a wet type brake-by-wire system. As a safety critical automotive electrical and/or electronic (E/E) system, DEHB shall be designed under the guideline of ISO 26262 in order to avoid unreasonable risk due to the malfunctions in the item. This paper explores how the Automotive Safety Integrity Level (ASIL) decomposition in the concept phase is influenced by the system architectures of DEHB. Based on a typical hazardous event, analysis on DEHB with the same system architecture as the Electro-mechanical Braking system (EMB) is carried out, which is taken as the basis for comparison. Two types of DEHB with different system architectures are then analyzed. Results show that the adoption of hydraulic backup enables ASIL decomposition in the pedal unit. The adoption of both hydraulic backup and normally open balance valves offers the opportunity to perform ASIL decomposition in the brake actuator system of DEHB.

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Handling Low and High Demand Mode on Safety Instrumented Function

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v5i4.pp742-749 ◽

2015 ◽

Vol 5 (4) ◽

pp. 742

Author(s):

Totok R. Biyanto ◽

Franky Kusuma ◽

Hendra Cordova ◽

Yerry Sutatio ◽

Ridho Bayuaji

Keyword(s):

Test Interval ◽

High Demand ◽

Event Frequency ◽

Demand Rate ◽

Hazardous Event ◽

Exponential Formula ◽

Simplified Formula

In this paper, demand rate and hazardous event frequency considerations which effect to the error on the SIL calculation will be discused. The various value of hazardous event frequency and demand rate will be evaluated in this paper. The result of this paper is when hazardous event frequency 10E-06/year and PFD’s safeguard 0.00002, with test interval 1 year, the SILs of low and high demand start showing different level at demand 5.1/year. At that point, we shouldn’t use simplified formula for low demand, because it will make different SIL with the exponential formula and simplified high demand formula. The requared SIL targets are SIL 2 and SIL 1, for exponential formula and simplified high demand formula, respectifely. Hence, it should be taken more attention and consideration for various value of hazardous event frequency with various demand rate.

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Security and Reliability Research of Remote Access for Subsea Blowout Preventer System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.467.615 ◽

2013 ◽

Vol 467 ◽

pp. 615-620

Author(s):

Bao Ping Cai ◽

Yong Hong Liu ◽

Zeng Kai Liu ◽

Shi Lin Yu ◽

Yun Wei Zhang ◽

...

Keyword(s):

Virtual Private Network ◽

Remote Access ◽

Safety Integrity Level ◽

Blowout Preventer ◽

Hardware Configuration ◽

Security And Reliability ◽

Ethernet Network ◽

Product Approach ◽

Private Network ◽

Ethernet Card

Remote access for subsea blowout preventer system based on virtual private network technology over the Internet is developed. The hardware configuration and software development for remote access are described. The redundant Ethernet networks, cryptography with smart card and firewall are used to improve the security and reliability. With respect to common cause failure, the performances of Ethernet network are evaluated by using Markov method with multiple error shock model. Due to the complexity, the system is split into a set of independent modules which are merged with Kronecker product approach. The availability and reliability are researched. The reliability analysis shows that the redundant Ethernet network equipments have safety integrity level of 4, which meets the requirement of remote access of subsea blowout preventer system. In addition, the effects of failure rate of Ethernet card on the availability and reliability are obvious, which should be paid more attention when designing the Ethernet network.

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Estimation of average hazardous-event-frequency for allocation of safety-integrity levels

Reliability Engineering & System Safety ◽

10.1016/s0951-8320(99)00030-7 ◽

1999 ◽

Vol 66 (2) ◽

pp. 135-144 ◽

Cited By ~ 36

Author(s):

Y Misumi ◽

Y Sato

Keyword(s):

Event Frequency ◽

Hazardous Event

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A Bayesian network based method for reliability analysis of subsea blowout preventer control system

Journal of Loss Prevention in the Process Industries ◽

10.1016/j.jlp.2019.03.004 ◽

2019 ◽

Vol 59 ◽

pp. 44-53 ◽

Cited By ~ 8

Author(s):

Zengkai Liu ◽

Yonghong Liu

Keyword(s):

Control System ◽

Bayesian Network ◽

Reliability Analysis ◽

Blowout Preventer

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Review of Technological Advancements and HSE-Based Safety Model for Deep-Water Human Occupied Vehicles

Marine Technology Society Journal ◽

10.4031/mtsj.48.3.7 ◽

2014 ◽

Vol 48 (3) ◽

pp. 25-42 ◽

Cited By ~ 5

Author(s):

Narayanaswamy Vedachalam ◽

Gidugu Ananada Ramadass ◽

Malayath Aravindakshan Atmanand

Keyword(s):

Deep Water ◽

Capital Expenditure ◽

Mean Time Between Failures ◽

Safety Integrity Level ◽

Geological Surveys ◽

Time Between Failures ◽

High Resolution Bathymetry ◽

Safety Systems ◽

Mean Time ◽

Safety And Environment

AbstractThis paper reviews the latest advancements in subsea technologies associated with the safety of deep-water human occupied vehicles. Human occupied submersible operations are required for deep-water activities, such as high-resolution bathymetry, biological and geological surveys, search activities, salvage operations, and engineering support for underwater operations. As this involves direct human presence, the system has to be extremely safe and reliable. Based on applicable IEC 61508 Standards for health, safety, and environment (HSE), the safety integrity level requirements for the submersible safety systems are estimated. Safety analyses are done on 10 critical submersible safety systems with the assumption that the submersible is utilized for 10 deep-water missions per year. The results of the analyses are compared with the estimated target HSE requirements, and it is found that, with the present technological maturity and safety-centered design, it is possible to meet the required safety integrity levels. By proper maintenance, it is possible to keep the mean time between failures to more than 9 years. The results presented shall serve as a model for designers to arrive at the required trade-off between the capital expenditure, operating expenditure, and required safety levels.

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Effects of Perforated Flow Tube on the Flow Field of a Blowout Well

SPE Journal ◽

10.2118/179730-pa ◽

2016 ◽

Vol 21 (04) ◽

pp. 1470-1476 ◽

Cited By ~ 1

Author(s):

Ebrahim Hajidavalloo ◽

Saeed Alidadi Dehkohneh

Keyword(s):

Flow Field ◽

Flow Tube ◽

Gas Well ◽

Safety Measures ◽

Team Members ◽

Well Control ◽

Blowout Preventer ◽

New Type ◽

Oil Gas ◽

Simple Flow

Summary When a blowout oil/gas well catches fire, usually a flow tube is used to detach the fire from the wellhead and provide appropriate conditions for operating team members to approach the well and install the blowout-preventer (BOP) cap. Using the flow tube above the wellhead creates powerful suction around the tube that may jeopardize the safety of crew members. To reduce the power of suction around the well, a new perforated flow tube instead of simple flow tube was introduced. To understand the effect of this new type of flow tube, modeling and simulation of the flow field around the blowout well were performed for both simple and perforated types of flow tube with Fluent 6.3.26 (2003) and Gambit 2.3.16 (2003) softwares. Different parameters around the well mouth were compared in both designs. The results showed that using the perforated flow tube decreases the vacuum around the well by 33% compared with the simple flow tubes. Thus, application of the perforated flow tube can be recommended in well-control operations for safety measures.

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Temperature Measurement Applications in Power Plants

ASME 2009 Power Conference ◽

10.1115/power2009-81172 ◽

2009 ◽

Author(s):

Ravi Jethra

Keyword(s):

Power Plant ◽

Temperature Measurement ◽

Power Plants ◽

New Technologies ◽

Measurement Information ◽

Safety Integrity Level ◽

Safety And Reliability ◽

Technical Advances ◽

Incorrect Measurement ◽

Major Equipment

Temperature is one of the most widely measured parameters in a power plant. Temperature is monitored and also used for control in some areas. The paper covers some of the basics of Temperature measurement, and leads into some of the technical advances that impart higher a degree of safety and reliability to power plant operation. These advances are based on some of the latest and innovative technologies that are being implemented in process instrumentation. Irrespective of the type of power plant (coal-fired, Oil or gas based), temperature measurement remains high on the list for operational excellence throughout the plant. Implementation of some of the new technologies results in improved Safety and lower installation and maintenance costs. Incorrect measurement information due to temperature effects, non linearity or stability can result in major equipment getting damaged. Ensuring instruments that have minimal downtime from a maintenance standpoint, not just devices that have been evaluated to provide Safety Integrity Level service in Safety Instrumented Systems, is crucial for daily operations in a power plant.

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