Lake Monitors Inc., Pneumatic
In-Line Flow Rate Monitors

In-Line Pneumatic Flow Rate Monitors
(For 1/4 To 2 Inch Pipe Sizes)

Engineering Specifications
The pneumatic in-line flow rate monitor shall:

• Use the variable annular orifice technique with compression spring recovery.
• not require inlet or outlet straight plumbing or require vertical pipe mounting
• have a measuring accuracy of +/-2.5% of full scale in the centerg third of the measuring range and +/- 4% of full scale accuracy over the entire flow measuring range
• have a stainless steel sharp-edged orifice
• have a weather-tight external construction

• Three Materials of Construction:
Select from aluminum, brass or stainless steel.

• Flexible Mounting Requirements:
Allows the designer to mount the monitor in any orientation; horizontal, vertical or upside down.

• Superior Exterior Design:
Weather-tight for use outdoors and/or on systems where washdowns are required.

• Multi-Use:
Versatile monitors can be used to verify air compressor outputs and to test pneumatic machinery and tools for proper air consumption.

• Rugged and Reliable:
Designed as a hydraulic service tool, this monitor will provide years of maintenance free performance.

• High Pressure Operation:
The magnetically coupled follower allows operation to 6000 PSIG and use with opaque liquids

• Twenty-three Different Ports Available. Standard selection of NPT, SAE and BSP permits system design versatility.

• Low Cost Precision:
Mid-scale measuring accuracy: within 2.5%. Full-scale accuracy: within 4%.

Materials of Construction: Wetted Components

	Aluminum	Brass	Stainless Steel
High-pressure casing, end ports and tapered shaft	Aluminum	Brass	#304 Stainless Steel
Seals	Buna-N (STD), EPR, Viton® or Kalrez ®	Buna-N (STD), EPR, Viton® or Kalrez ®	Viton® with Teflon® backup (STD), Buna-N, EPR or Kalrez ®
Transfer Magnet	Teflon® coated Alnico	Teflon® coated Alnico	Teflon® coated Alnico
Floating Orifice Disk	Stainless Steel	Stainless Steel	Stainless Steel
All other internal parts	Stainless Steel	Stainless Steel	Stainless Steel

Materials of Construction: Non-Wetted Components

	Aluminum	Brass	Stainless Steel
Window Tube	Polycarbonate (STD), Pyrex	Polycarbonate (STD), Pyrex	Polycarbonate (STD), Pyrex
Window Seals	Buna-N (STD), Teflon®	Buna-N (STD), Teflon®	Buna-N (STD), Teflon®

Teflon, Viton and Kalrez are registered trademarks of duPont de Nemours & Co.

Performance Specifications:

Measuring Accuracy:	2.5% of full-scale in the center third of the measuring range; 4% of full-scale over the entire scale range.
Repeatability:	1% of full-scale
Flow measuring range:	1.5-1300 SCFM(1-610 SLPH)
Pressure differential:	see graphs below
Maximum operating pressure:	aluminum and brass monitors: 600PSIG(40Bar) stainless steel monitors: 1000 PSIG (70 Bar)
Maximum operating temperature:	240F (116C) Note: for operation to 600°F (316°C), see our High Temperature Data sheet.
Standard calibration fluids:	air @ 70F (21C), 1.0 sg and 100 PSIG (6.8 Bar)

Mechanical

DIM	Series 3	Series 4	Series 5	Series 5
A	1-7/8" (48mm)	2-3/8" (60mm)	3-1/2" (90mm)	3-1/2" (90mm)
B	6-9/16" (167mm)	7-5/32" (182mm)	10-1/8" (258mm)	12-5/8" (322mm)
Port Sizes	NPTF: 1/4", 3/8", 1/2" SAE: #6, #8, #10 BSP: 3/8", 1/2"	NPTF: 3/4", 1" SAE: #12, #16 BSP: 3/4", 1"	NPTF: 1-1/4", 1-1/2" SAE: #20, #24 BSP: 1-1/4", 1-1/2"	NPTF: 2" SAE: #32 BSP: 2"