WOODWARD Turbine Shutdown Trip Block Assemblies

WOODWARD Turbine Shutdown Trip Block Assemblies

Product Overview

The QuickTrip trip block component is carefully designed for steam, gas, and turbine shutdown systems, suitable for mechanical or generator driven turbines using low-pressure (5-25 bar/73-363 psi) hydraulic trip oil manifolds. Its core function is to quickly discharge the tripping oil main of the turbine, providing a solid guarantee for the safe shutdown of the turbine in emergency situations.

Model and Features

Represented by the 9907-1978 model, this component has a unique design and notable features.

Fault tolerant design: Three independent rotary valves are used, working together based on a 3-to-2 voting mechanism. This design ensures that in the event of any component failure, such as valve actuators, valves, circuits, or connectors, it will not cause false tripping, greatly improving the reliability of the system and fully complying with the API-670 industry standard. For example, in a complex industrial environment, a valve driver may experience a brief malfunction due to electrical interference, but due to the 3-to-2 voting mechanism, the system can still accurately determine and operate normally without causing unnecessary downtime, ensuring the continuity of production.

Corrosion resistant and self-cleaning design: The components are made of corrosion-resistant materials, with a rotating chip shear force of 25 lbf and a self-cleaning port design. This enables it to operate stably in harsh conditions with dirty or contaminated oil, especially suitable for steam turbine applications. During the operation of steam turbines, their lubricating oil is usually used to drive hydraulic turbine control valve actuators, and the oil system of steam turbines often mixes with dirt, metal shavings, water, and other pollutants such as Babbitt metal, ammonia, etc. In addition, due to the high operating temperature of the steam turbine, the turbine oil is prone to decomposition, producing sludge like substances, resulting in varnishing of internal system components. The 9907-1978 model trip block component, with its special design, can effectively address these issues and ensure the normal operation of the system.

Online maintenance function: This component supports online maintenance. When the turbine is in online operation, users can replace key components such as electrical modules, solenoid valves, circuits, drivers, etc. This feature greatly improves the maintainability of the system and reduces downtime caused by equipment maintenance. For example, during peak production periods, if a certain solenoid valve malfunctions, it can be replaced online without stopping the machine, avoiding the impact of downtime maintenance on production progress.

Technical parameters

Working voltage: 24 VDC, stable low voltage power supply, suitable for various electrical system environments, ensuring the stable operation of component control circuits.

Maximum supply pressure: 500 psi, capable of withstanding high pressure hydraulic oil input, meeting the demand for discharge pressure of the trip oil main pipe under different operating conditions.

Applicable oil types: Mineral oil, synthetic oil, or Fyrquel EHC base oil can be used, with a wide range of oil adaptability and compatibility with different types of turbine oil systems.

Operating temperature range: -40 to+85 ° C (-40 to+185 ° F), can operate normally in extreme environmental temperatures, ensuring stable performance whether in cold outdoor environments or high-temperature industrial plants.

Operating oil temperature range:+15 to+70 ° C (+59 to+158 ° F). There are clear requirements for the oil temperature during operation to ensure that the hydraulic components inside the components can work normally within the appropriate oil temperature range, avoiding the impact of high or low oil temperature on component performance.

Diagnostic testing

Given the adoption of a 3-to-2 configuration, diagnostic testing can be conducted while QuickTrip is online and the turbine is running. The testing program will set the tripping output of the tested module to a tripping state (configured as a power-off state for power-off tripping), and only test one module at a time.

Users can automate the testing process by using the built-in "Automatic Sequence Testing" feature in ProTech TPS, or by leveraging ProTech's programmability and test mode configuration. During the testing process, it is necessary to verify whether there is a running alarm (failure to power on and enter the running state), and to verify the trip time of each module by checking the trip cycle time log. This log will display the last 20 trip events, as well as the time interval from the control signal dropping to the QuickTrip valve rotating to the open position and the trip position sensor sending a trip signal to ProTech. Under normal circumstances, this trip time should be less than 50 ms. If the QuickTrip module (valve) malfunctions upon receiving a command to rotate to open or close, or if the trip time exceeds 50 ms, timely maintenance and troubleshooting are required to ensure the normal operation of the components and the safety of the turbine.

Key advantages

1. High reliability fault-tolerant design

3-for-2 voting mechanism: By working together with three independent rotary valves, any single component failure (such as valve driver, circuit or connector) will not trigger false tripping, meeting the API-670 industry standard and suitable for critical industrial scenarios of continuous operation. For example, when a certain solenoid valve fails due to voltage fluctuations, the other two valves can still maintain normal system logic and avoid unnecessary shutdowns.

Fault isolation capability: Each module operates independently, and the faulty module can be isolated online without affecting the overall system operation, improving the stability of turbine operation.

2. Adaptability to harsh working conditions

Corrosion resistant materials and self-cleaning design: Using corrosion-resistant materials (such as stainless steel valve body), combined with 25 lbf rotating chip shear force and self-cleaning ports, can effectively deal with dirt, metal shavings, and decomposition products (such as Babbitt alloy particles and ammonia pollution commonly found in steam turbines) in the oil, preventing port blockage or valve body corrosion.

Wide temperature operation capability: The operating temperature range is -40 to+85 ° C, suitable for extreme environments (such as outdoor low-temperature or high-temperature factories), and the operating oil temperature range is+15 to+70 ° C, compatible with hydraulic oils of different viscosities.

3. Maintain convenience and efficiency

Online maintenance function: Key components such as electrical modules and solenoid valves can be replaced without stopping the machine, reducing unplanned downtime. For example, during peak production periods, faulty solenoid valves can be directly replaced to avoid production capacity losses caused by maintenance.

Automated diagnostic support: Through the "automatic sequence testing" function of ProTech TPS, module trip time (<50 ms) and operating status can be verified online, potential faults can be detected in advance, and maintenance costs can be reduced.

4. Compliance with safety standards

Multi certification guarantee: Designed to comply with API-670 standards, supporting Canadian/US hazardous site certification and EU ATEX directive, suitable for high-risk industries such as petroleum and chemical, ensuring safety regulatory requirements.

Quick response capability: Trip time ≤ 50 ms, can quickly cut off the power source of the turbine in emergency situations, preventing the expansion of dangerous working conditions such as overspeed and overpressure.

Precautions

1. Installation and environmental requirements

Oil cleanliness control: It is necessary to ensure that the hydraulic oil cleanliness meets the ISO 4406 standard (recommended ≤ 18/16/13) to avoid valve jamming caused by oil contamination. If the oil contains water or particulate matter, it needs to be paired with a high-precision filter (filtration accuracy ≤ 10 μ m).

Temperature limit: The operating oil temperature should be controlled between+15 and+70 ° C. If the oil temperature exceeds 70 ° C, it may lead to increased oxidation of the oil, and a cooling system needs to be configured; When the temperature is below 15 ° C, the viscosity of the oil increases, which may affect the tripping response speed and requires preheating in advance.

2. Maintenance and testing standards

Regular diagnostic testing: Perform a trip time test at least once every quarter, and record the last 20 trip events through ProTech TPS. If a module trips for more than 50 ms, immediately investigate valve wear or hydraulic system leaks.

Precautions for component replacement: When replacing solenoid valves or electrical modules online, the corresponding module power should be disconnected first, and special tools should be used for disassembly to avoid short circuits caused by live operation; After replacement, it is necessary to perform functional verification again.

3. Oil compatibility management

Do not mix oil: Mixing different types of oil (such as mineral oil and synthetic oil) may cause viscosity changes or additive precipitation. It is necessary to ensure that the system uses a single type of oil and regularly test the physical and chemical indicators of the oil (such as acid value and viscosity index).

Fyrquel EHC base oil special treatment: When using this type of oil, attention should be paid to its flame retardant properties, which may affect the sealing material. Fluororubber (FKM) seals should be selected to avoid swelling and failure of ordinary rubber parts.

4. Emergency handling of faults

Troubleshooting of accidental tripping: In case of unexpected tripping, priority should be given to checking the alarm logs of ProTech TPS to confirm whether it is caused by sensor failure or line interference; At the same time, check whether the pressure of the tripped oil main is abnormal (normal working pressure 5-25 bar).

Emergency manual operation: If the automated diagnostic system fails, the trip valve can be forcibly opened by manually operating the knob, but it is necessary to ensure that the operator wears protective equipment to avoid the risk of high-pressure oil spray.