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Can Oil Pass Through a Strainer? How Pre-Filtration Works in Lubrication Systems
Can Oil Pass Through a Strainer? How Pre-Filtration Works in Lubrication Systems
2025-05-20

In any efficient and reliable lubrication system, oil cleanliness is a core factor affecting equipment lifespan and operational efficiency. Strainers, as the front-line filtration devices in lubrication systems, play a critical role in pre-filtration. However, engineers and operators often raise the following questions: Can oil pass through strainers smoothly? What exactly is the function of a strainer? How does it differ from subsequent fine filters?   This article systematically explains the role of strainers in lubrication systems, covering their working principles, pre-filtration objectives, and practical applications across different systems.   1. Can Oil Pass Through a Strainer?   Answer: Yes, but with limitations.   (1) Strainer Structure Allows Oil Flow A strainer is fundamentally a low-precision filter made of stainless steel mesh or perforated metal plates. It features uniform pores, typically sized between 80–500 μm (micrometers), allowing most clean oil to flow through unimpeded.   (2) Contaminants Are Blocked Particles such as metal shavings, seal fragments, and carbon deposits in the oil are intercepted by the strainer, preventing them from entering the oil pump or other critical components.   (3) Oil Temperature and Viscosity Affect Flow Efficiency Low temperatures or high-viscosity oil may reduce flow rates or even cause blockages. This is one reason for low oil pressure during system startup.   2. Objectives and Significance of Pre-Filtration   (1) Protecting the Oil Pump Internal pump components (gears, impellers, or plungers) are highly sensitive to solid particles. Pre-filtration prevents particles from entering the pump, avoiding premature wear or seizure.   (2) Reducing Load on Primary Filters By intercepting large contaminants, strainers allow primary filters (e.g., oil filter cartridges) to focus on finer impurities, extending their service life and maintaining stable system flow.   (3) Lowering System Failure Rates Pre-filtration reduces risks such as pump failure, orifice blockages, and lubrication breakdown caused by foreign particles, enhancing overall system reliability.   3. Typical Applications of Pre-Filtration Devices   Application System Strainer Installation Position Strainer Type Internal Combustion Engine Lubrication Oil sump → Pump inlet Coarse metal strainer Hydraulic Systems Tank outlet → Pump suction port Suction strainer or basket strainer Turbine Lubrication Systems Pump inlet Dual-chamber switchable suction strainer Transmission/Clutch Systems Oil sump → Circulation pump inlet Perforated plate + magnetic strainer   4. Design and Usage Considerations for Strainers   (1) Pore Size Selection Must Align with System Precision Requirements 80–100 μm: Typical for engine oil systems. 150–300 μm: Used in hydraulic equipment. >400 μm:  Suitable for low-pressure or open-loop systems.   (2...

Are Ball Valves Suitable for Water Systems? A Practical Guide for Engineers & Installers
Are Ball Valves Suitable for Water Systems? A Practical Guide for Engineers & Installers
2025-04-30

Ball valves, with their simple structure, easy operation, and excellent sealing performance, have become widely used control components in both industrial and residential sectors. Particularly in water supply systems, an increasing number of engineers and installers are choosing ball valves as the primary fluid control device. But are ball valves truly suitable for water systems? How should one properly select and install them to ensure long-term stable operation? This article provides a comprehensive overview from the perspectives of structural principles, performance characteristics, and application recommendations. 1. Advantages of Ball Valves in Water Systems (1) Quick Opening and Closing Ball valves can complete the opening and closing operation with a simple 90° rotation, making them easy to operate and highly responsive—ideal for emergency situations or water systems that require frequent switching.   (2) Excellent Sealing Performance High-quality ball valves are equipped with PTFE or reinforced sealing materials, enabling zero leakage. They are particularly suitable for water supply systems in residential buildings, commercial complexes, and industrial facilities where sealing performance is critical.   (3) Compact Structure and Space-Saving Compared to gate valves or globe valves, ball valves occupy less space and offer flexible installation, making them ideal for water modules with high equipment integration.   (4) Strong Corrosion Resistance Ball valves made of stainless steel, brass, or plastic materials (such as UPVC) offer excellent corrosion resistance, capable of handling various water qualities (soft water, hard water, reclaimed water) and different additives.   2. Application Scenarios Analysis Ball valves are suitable for the following types of water systems: (1) Domestic Water Systems: Such as internal building water supply, point-of-use control for sanitary fixtures, and garden irrigation systems. (2) Industrial Water Systems: Such as cooling water circulation systems, boiler feedwater systems, and water supply for cleaning equipment. (3) Water Treatment Systems: Including reverse osmosis pretreatment, greywater recycling, and wastewater transfer processes. (4) Special Applications: High-pressure hot water systems or cleaning water containing chemical additives.   However, caution should be exercised in the following scenarios: (1) High-Frequency Modulation Conditions Standard ball valves are not suitable for precise flow regulation. It is recommended to use V-port ball valves or control-type electric ball valves. (2) Water Containing Sand, Gravel, or High Levels of Suspended Solids A Y-strainer should be installed to prevent particle blockage or damage to the sealing surfaces. (3) High-Temperature Hot Water Systems High-temperature ball valves with metal sealing structures should be selected to prevent seal aging and deformation.   3. Key Selection Criteria To ensure stable operation o...

What Causes Ball Valve Failure? 5 Common Issues and How to Prevent Them
What Causes Ball Valve Failure? 5 Common Issues and How to Prevent Them
2025-04-11

Ball valves are widely used industrial flow control components, commonly found in applications such as water treatment, oil and gas, chemical processing, HVAC systems, and the food and pharmaceutical industries. Thanks to their compact structure, quick shut-off capability, and excellent sealing performance, ball valves play a critical role in various fluid systems. However, even the most reliable ball valve can encounter failures after prolonged operation. When a ball valve fails, it can compromise the stability of the entire system and, in severe cases, lead to media leakage or even safety incidents. Therefore, understanding the root causes of ball valve failure and implementing effective preventive measures is essential for engineers and maintenance personnel.   1. Seal Failure Cause: Seal failure in ball valves is often caused by seat wear, debris accumulation, or aging of sealing materials. This issue is especially common in high-temperature, high-pressure, or corrosive media environments. Prevention Tips: To extend the service life of the seal, choose ball valves with PTFE or metal seats that are compatible with the process media. Regularly clean the seat area and establish a replacement schedule based on the operating conditions.   2. Corrosion or Scratches on the Ball Surface Cause: When a ball valve is used with media containing acids, alkalis, high salt content, or abrasive particles, improper material selection can lead to corrosion, pitting, or surface scratches. These issues reduce sealing performance and affect smooth operation. Prevention Tips: Select stainless steel ball valves (such as 304 or 316 grades) or special alloy ball valves based on the specific media characteristics. Additionally, install a strainer or filter to minimize solid particle intrusion and protect the valve internals.   3. Stem Breakage or Seizure Cause: The valve stem, which transmits torque to the ball, may experience metal fatigue and fracture under frequent operation or excessive torque. Seizure can also occur due to bearing wear or lack of lubrication. In some low-quality ball valves, insufficient structural design margin further increases the risk of stem failure. Prevention Tips: Use ball valves with blow-out proof stem designs to enhance operational safety. Ensure that operating torque stays within the valve’s rated limits, and apply lubricant regularly to reduce friction and wear, extending service life.   4. Improper Installation or Operation Cause: Human errors such as incorrect installation direction, loose flange connections, or frequent forceful operation are major contributors to early ball valve failure. In the case of electric or pneumatic ball valves, signal control errors can also lead to misoperation or valve jamming. Prevention Tips: Always follow the manufacturer’s installation guidelines, ensure proper alignment and secure flange connections. Install limit switches and torque protection devices to safeguard...

MSS SP-81 Manual Lug Type Knife Gate Valve Bi-directional
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MSS SP-81 Manual Lug Type Knife Gate Valve Bi-directional

The knife gate is a bi-directional lug type valve designed according to MSS-SP-81 and for industrial service applications. The design of the body and seat assures non-clogging shut off on suspended solids in industries.

  • Payment:

    30% when order confirmed, 70% before shipment
  • Product Origin:

    China
  • Color:

    Customization
  • Shipping Port:

    Shanghai, China
  • Lead Time:

    30~60 days Ex Works after order confirmation
  • Material:

    2205
  • Method of Operation:

    Handwheel
Inquiry now
Product Detail

Quick Detail

Type

KnifeGate Valve

Size

6''

Design Pressure

150LB

Construction 

Knife Type Gate Valve

Connection Type

Lug Type, RF

Operation Type

Hand wheel

Body Material

2205

Seat Material

EPDM

Design Code

MSS SP-81

Flange Dimensions

ASME B16.5

Temp. Range:

-29~.+120℃

Medium

Water, Oil and Gas

Origin

China


Features

All stainless steel design

Standard knife gate valves: NPS 2–24 (DN 50–600)  

Bolted bonnet knife gate valves: NPS 4–24 (DN 50–600)

ASME Classes: 1690-4500  

0-14ph packing standard

Locking device on standard knife gate valve

Environmentally friendly bi-directional bolted bonnet and standard body styles

Resilient and metal seats


Technical Drawing


Before Manufacturing

Nameplate&Packaging


Reports

For each order, Dervos will provide inspection reports to show you the whole inspection process and results. Plus, we will provide material report to let you know that the material we provide is as per standards.



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If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.

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    If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.

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