1. Product Overview
WF-FQ11-6 straight internal thread float ball sight flow indicator is a compact heavy-duty mini inline visual flow monitor independently developed by TechWF. Adopting one-piece precision cast 304 stainless steel cylindrical body with symmetrical dual BSP/NPT internal thread ports, top snap-on borosilicate sight window and single anti-corrosion floating ball indicator. Simple structure, small footprint and reliable performance, it is widely applied in industrial equipment cooling, light fine chemical, agricultural greenhouse irrigation, HVAC heating, yacht and coastal marine small-bore threaded auxiliary pipeline systems.
This sight glass is integrally cast from 304 stainless steel with seamless smooth inner cavity, symmetrical full internal thread for bidirectional screw installation. The top detachable transparent sight window holds a single solid anti-corrosion float ball. When fluid flows through the pipeline, buoyancy lifts the float ball upwards for clear visual confirmation of flowing status; if flow stops or backflow occurs, the float sinks down to remind operators of pipeline cut-off, empty pipe or reverse medium. It provides low-cost real-time flow monitoring for small circulation pumps, dosing pipelines, branch irrigation lines and yacht cooling loops to avoid dry-running, cavitation and equipment overheating damage.
All finished units pass hydraulic burst pressure test, salt spray anti-corrosion aging test, thread sealing leakage test and hot-cold alternating cycle validation before factory delivery, maintaining stable zero-leak continuous operation under purified water, glycol, weak acid/alkali and low-salinity seawater media worldwide.
2. Premium Technical Specifications
- Body Material: 304 stainless steel precision casting, matte passivated anti-rust finish, food & marine sanitary compliant
- Connection Standard: Dual symmetrical BSP / NPT internal thread, customizable sizes DN15~DN50
- Sight Window: Thick high-pressure resistant round borosilicate glass, 270° vertical panoramic viewing without blind spots
- Indicator Core: Solid PP floating ball, lightweight, chemical resistant, rises under fluid buoyancy
- Sealing Assembly: Single-layer EPDM / FKM O-ring gaskets; EPDM for clean water & edible media, FKM for weak solvent & brine media
- Nominal Working Pressure: PN16 standard grade; PN20 high-pressure reinforced version optional
- Operating Temperature Range: -10℃ ~ +120℃
- Flow Channel: Straight full-bore inner cavity, zero extra pressure drop, polished smooth inner wall reduces limescale, organic and fertilizer sediment adhesion
- Structural Feature: Compact integrated cylindrical threaded body, thread lock top glass cover, fully disassemblable to take out float ball for flushing without removing the whole fitting from pipelines
3. Core Competitive Advantages
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Integral Seamless Cast 304 Stainless Steel Anti-Corrosion Cylindrical Body
One-piece precision casting eliminates casting pores and internal stagnant dead zones; matte passivation delivers excellent rust resistance under humid, coastal weak salt fog environments. Smooth seamless inner surface prevents medium residue buildup, superior to brass sight glasses for weak acid and saltwater working conditions.
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Universal Symmetric Dual Internal Thread Bidirectional Installation
Identical standard internal threads on both inlet and outlet support bidirectional assembly, compatible with all common threaded pipe fittings without transition nipples, greatly shortening construction time for small-branch pipeline projects.
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Single Solid Float Ball Clear Flow Visualization
Solid colored float ball creates sharp contrast against transparent glass, easy to observe flow state even from a distance. No complex springs, paddles or dials; only buoyancy drives the ball, ultra-low failure rate and long service life.
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Zero Pressure Loss Full-Bore Unrestricted Flow Path
No protruding throttle obstacles inside the cavity, fully retains original pipeline flow capacity, perfectly suited for low-flow micro cooling circulation pipelines of machinery, heating and agricultural dosing equipment.
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Chemical-Inert Solid Float Ball Assembly
Solid PP float ball resists weak acid, alkali and light saltwater corrosion, lightweight and highly sensitive to tiny flow changes, no jamming or sticking after long-term continuous operation.
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Threaded Snap-On Top Cover Easy Maintenance
Thread locking top cover can be unscrewed by hand without special tools, quickly take out float ball to flush accumulated limescale, fertilizer sludge and oil deposits, convenient regular routine maintenance.
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Ultra-Compact Cylindrical Space-Saving Layout
Small vertical cylindrical threaded structure fits densely arranged instrument racks, narrow cabinet internal cooling lines and compact yacht engine room tiny piping where large split sight indicators cannot be installed.
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Simple Low-Maintenance Robust Mechanical Design
Only one moving component (float ball), no fragile swing plates, springs or scale components, minimal failure points, capable of 24-hour non-stop industrial continuous operation.
4. Global Cross-Industry Application Scenarios
Industrial Machinery & HVAC Cooling
CNC machine tool cooling threaded pipelines, injection molding machine auxiliary circulation lines, building heating small branch water pipes, solar hot water auxiliary circulation tubing; compact stainless steel body adapts to narrow equipment internal installation gaps.
Light Fine Chemical Industry
Neutral weak acid/alkali solvent small threaded branch pipelines, laboratory micro reagent delivery tubing, water-based coating low-pressure circulation loops; 304 stainless steel avoids metal ion contamination of chemical raw materials.
Large-Scale Precision Agriculture
Greenhouse nutrient solution branch irrigation threaded lines, farm small fertilizer dosing auxiliary pipelines, seedling watering micro sub-lines; anti-corrosion float ball reliably displays fertilizer liquid flow state.
Yacht & Coastal Light Marine Systems
Small yacht engine room cooling threaded circulation lines, coastal aquaculture low-salinity water auxiliary piping, onshore cooling water sub-loops; stainless steel passivation layer withstands weak coastal salt fog splash erosion.
Supplementary Auxiliary Fields
Industrial pure water pretreatment small branch pipelines, fire protection micro clean water threaded lines, compressor and hydraulic equipment auxiliary cooling circulation tubing.
5. Customization Support Service
- Material Customization: Standard 304 stainless steel, upgrade to 316 marine high anti-corrosion sanitary grade
- Thread Standard Customization: Custom BSPP, BSPT, NPT internal thread specifications
- Pressure Grade Customization: PN16 standard, PN20 high-pressure reinforced variant
- Sealing Material Matching: Food-grade EPDM for water & edible media, FKM fluororubber for weak acid/alkali solvent transportation
- Brand & Packaging Customization: Laser engraved customer LOGO on cylindrical body, neutral anti-collision export wooden case packaging; complete material & pressure test certificates provided for tender documentation
- Caliber Customization: DN15, DN20, DN25, DN32, DN40, DN50 non-standard threaded sizes available
6. Factory Quality Control Standards
All WF-FQ11 series threaded float ball sight indicators implement mandatory 100% full inspection prior to shipment. Standard factory testing items include hydraulic burst pressure test, thread sealing leakage test, salt spray long-cycle anti-corrosion aging test, float ball flow sensitivity test and cold-hot alternating cycle validation.
Complete stainless steel material certification, sanitary inspection reports and full pressure vessel test packages can be supplied to support global machinery cooling, light chemical, agricultural and coastal marine engineering tender reviews and equipment safety compliance audits.
Contact Information
Manufacturer: Wenzhou Weifeng Technology Co., Ltd.
Official Website: www.alvifeng.com
