KSM - All-Plastic Flow Meter and Switch for Liquids or Gases

Economical Variable Area Flow Meter for Industrial Applications

The KOBOLD KSM plastic variable area flowmeter delivers accurate, cost-effective flow measurement for industrial water, air, and chemical applications. This versatile plastic variable area flow meter, also commonly known as a rotameter, provides the same reliable measurement principle as expensive metal or glass rotameters at a fraction of the cost, making it ideal for budget-conscious projects requiring multiple measuring points or applications where plastic construction offers an economic advantages.

Measuring flow rates from 0.06…0.66 to 35…264 GPM for liquids and 0.5…3 to 40…400 SCFM for air, this higher-capacity meter addresses industrial requirements without the premium pricing of metal or glass variable area flow meters. The transparent rotameter tube provides direct visual flow indication maintaining ±4% full scale accuracy across the entire measurement range.

Understanding Variable Area Rotameter Value

Rotameters are one of the most economical flow measurement technologies for visual indication. The KSM exemplifies this cost-effective variable area approach, where flowing fluid lifts a float within a tapered tube to indicate flow rate. This simple principle makes rotameters the preferred choice for applications requiring reliable flow indication without complex electronics or external power. Two adjustable markers allow the user to designate desired flow conditions for instant verification.

Learn more about variable area and rotameter flow technology by visiting our in-depth Article on Variable Area and Rotameter Flow Technology.

Made in USA Rotameter - BABA Compliant Without Premium Pricing

Manufactured in Pittsburgh, Pennsylvania, the KSM flow meter meets Build America, Buy America (BABA) compliance requirements while maintaining competitive pricing. This domestic manufacturing streamlines procurement for federally funded projects including municipal water systems, wastewater facilities, and industrial infrastructure upgrades, all providing compliant variable area flow measurement without the premium cost. The KSM delivers immediate project qualification while reducing instrumentation costs, enabling managers to maximize measurement points within budgets and accelerate completion through readily available domestic inventory.

Versatile Rotameter Construction for Multiple Media Types

Plastic variable area flow meter construction provides dual benefits: significant cost savings compared to metal or glass rotameters for standard applications and inherent corrosion resistance for aggressive media. With no metal parts in contact with the media, measuring tubes in either Trogamide® or Polysulfone, and other wetted parts consisting of PVDF, PVC, or EPDM these meters offers excellent resistance and reliability. The Trogamid® option handles general water or air at reduced cost versus other variable area meters. The Polysulfone version accommodates aggressive acids and chemicals, providing one platform for diverse requirements.

Cost-Effective Variable Area Control with Optional Switches

Up to two optional bistable reed switches add automated monitoring to this economical rotameter. Switch configurations enable the flow meter to provide high/low alarms or flow setpoint indication at minimal cost, transforming the visual rotameter into a control device suitable for integration with common automation infrastructures.

The optional switch is a normally open reed contact activated by increasing flow. Rated for up to 230 VAC with mechanical switching that requires no external power. An IP65 housing provides suitable protection from dust and water ingress in industrial environments This simple approach reduces installation costs versus powered variable area instrumentation.

Variable Area Installation Flexibility Reduces System Costs

Multiple sizes ranging from 1” to 2-1/2” accommodate a variety of pipe diameters and flow rates. Standard PVC glue socket connections provide economical permanent installation. Optional female NPT threaded connections are also available.

Direct Reading Variable Area Scales for Water and Air

Water scales provide direct GPM readings and air scales offer SCFM readings. The flow meter has large, clear scales with contrasting floats to ensure easy reading from a distance. Percentage scales enable quick flow verification relative to system capacity.

Variable Area Rotameter Technical Specifications

Value-Focused Variable Area Solutions from American Manufacturing

KOBOLD's Pittsburgh facility combines American quality and competitive pricing with efficient variable area flow meter production. Engineering support assists with application evaluation, ensuring proper model selection for economic and technical requirements. The KSM variable area flowmeter represents an optimal balance of affordability and reliability for industrial flow measurement.