In the field of thermal power generation and industrial power, the steam turbine fire-resistant oil system (EH oil system) is the “heart of high-pressure hydraulic control”, and the reliability of its core component, the oil pressure transmission solenoid directional valve, is directly related to the safety of the unit. With its revolutionary anti-pollution design, the D1VW004CNJW91 solenoid directional valve has set a new technical benchmark in the industry. This article will deeply analyze the survival of this valve under extreme pollution conditions from three dimensions: material science, structural optimization, and system synergy.

I. Pollution challenges of EH oil system

The fire-resistant oil system uses triaryl phosphate synthetic oil. Although it has the safety advantage of a high ignition point of 665℃, its physical and chemical properties bring dual challenges:

• Oil sensitivity: Fire-resistant oil is easily affected by moisture and metal particles to produce hydrolysis and acidification, generating conductive colloids.
• System complexity: Multiple components such as servo actuators and accumulators work together to produce 0.5-10μm metal wear particles.

Traditional solenoid valves will have problems such as valve core jamming and response delay in oil containing 3% contamination (NAS 10 level), but the solenoid valve D1VW004CNJW91 can withstand extreme contamination conditions of NAS 12 level. The secret lies in four core technology breakthroughs.

II. Multi-level anti-pollution technology matrix

(1) Magnetic steel guard: three-stage adsorption filtration system

The solenoid valve D1VW004CNJW91 integrates a sintered metal filter element with a diameter of 140μm at the oil inlet, which is achieved through a gradient aperture design:

1. The first stage intercepts metal debris >50μm (such as wear products of the regulating valve oil motor)
2. The second stage magnetic filter absorbs ferromagnetic particles (drawing on the principle of EH oil tank magnetic filter)
3. The third stage 10μm precision filter element ensures the cleanliness of the oil entering the valve cavity

Measured data show that this design reduces the passing rate of particles below 5μm to 1/8 of that of traditional valves, and the pressure drop only increases by 0.3MPa.

(2) Dynamic seal: dance of elastomer and metal

Adopting fluororubber (FKM) sealing technology, the valve core surface is hard chrome plated (thickness 15-20μm), with a hardness of HRC65, which resists particle erosion. The stepped sealing structure forms a dynamic oil film and establishes a self-cleaning flow field within the 0.1mm matching gap. The redundant seal design allows the valve to maintain 80% of its sealing efficiency when a single seal fails. In an accelerated life test containing 0.1% by weight of aluminum oxide abrasive, the valve continued to work for 5,000 hours without internal leakage.

III. Electromagnetic drive: Precise control in polluted environments

(1) Super strong electromagnetic system

The H-class insulation (180°C) wet electromagnet is used. Its core innovation lies in the dual-coil redundant design, which can maintain 75% of the driving force when a single coil fails. The magnetic circuit optimization increases the effective suction force to 1.8 times that of traditional valves, overcoming the viscous resistance caused by pollutants. The 0.5A low operating current design reduces the risk of arc carbon deposition. In oil with sudden viscosity changes (such as a 30% increase in viscosity due to water intrusion), the solenoid valve D1VW004CNJW91 can still ensure a response speed of <15ms.

(2) Intelligent fault-tolerant mechanism

Integrated pressure compensation pilot control module: real-time monitoring of the P→A and B→T oil circuit pressure differences, and dynamic adjustment of the pilot oil flow. When the valve core displacement deviation is detected to be >5%, the high-frequency oscillation cleaning program is automatically triggered three times. Equipped with dual LVDT redundant feedback to ensure the position accuracy of ±0.05mm3 under polluted conditions.

IV. System synergy: protection from components to ecology

(1) Oil regeneration system

Integrated with the EH system self-circulating oil filter device: diatomaceous earth-fiber filter is regenerated in series to maintain the acid value (KOH) <0.15mg/g. Online moisture monitoring module automatically starts the vacuum dehydration program after triggering the alarm. The forced regeneration cycle is 8 hours per week to maintain the oil cleanliness at ISO 17/14/11.

(2) Intelligent operation and maintenance strategy

Predictive maintenance system based on the Internet of Things: monitor the valve core movement current waveform and identify early jamming characteristics (such as a sudden increase of 15% in peak current). The differential pressure sensor tracks the filter element blockage in real time with an accuracy of ±0.02MPa. Combined with historical data, the remaining life model is established to achieve 72 hours of early warning of failure.

In the power industry, the D1VW004CNJW91 solenoid directional valve, with its excellent anti-pollution ability, not only protects the safety red line of the turbine, but also redefines the reliability standard of high-pressure hydraulic components.

When looking for high-quality, reliable oil pumps, YOYIK is undoubtedly a choice worth considering. The company specializes in providing a variety of power equipment including steam turbine accessories, and has won wide acclaim for its high-quality products and services. For more information or inquiries, please contact the customer service below:

E-mail: sales@yoyik.com
Tel: +86-838-2226655
Whatsapp: +86-13618105229

Yoyik offers various types of spare parts for steam turbines, generators, boilers in power plants:
proportional solenoid 4WE10Y-L3X/EG220NZ5L
ESV SOV 4WE10Y-20/AG110NZ4
Electric stop valve J961Y-P56160V
Pump Shaft CZ80-160
solenoid valve SCG553A017MS-230/50
accumulator valve NXQ-A1.6/20-H-HT
Servo valve G761-3024B
Stop valve J61Y-200
Electric steam trap J961WG-P5516V
Dermal vesicle NXQA-40/31.5-L
Check valve H44H-16C
Electric regulating valve (electric pressure holding valve) T968Y-1500SPL WCB
steam turbine stop valve WJ25F3.2P
液压阀 F3DG5S2-062A-220DC-50-DFZK
starting oil solenoid valve 4WE10D50/EG220N9K4/V
Valve G761-3039B
Vane Pump V20-1P8P-1C11
Instrument valve J61Y-P55150V 12Cr1MoV
VALVE, CONTROL; TYPE: FLOW, SERVO G761-3002B
Stop valve J961Y-100V
Stop valve J61Y-1500(I)SPL
ball valve M-3SEW6U36/420MG24N9K4
accumulator bracket NXQ A10/31.5-L
boiler main steam stop valve WJ65F1.6P
Throttle valve L61Y-25
DIAPHRAGM FOR BLADDER ACCUMULATORS NXQ2-L63/31.5
Electric gate valve Z962H-200 WCB
Block valve SD61H-100I WC6
solenoid valve coil 230v J-220VAC-DN10-D/20B/2A
RING,SEAL 100AY67X6-62
Pressure reducing valve ZZYP-17B
Electric stop valve body J961Y-630P SA-182F347H
solenoid dc valve D1VW004CNJW91