Blue-White F-550 Acrylic Variable Area Flow Meter 75 LPM

F-550 is a one-piece acrylic variable area flow meter from Blue-White covering 0.025 to 20 gallons per minute (0.1 to 75 litres per minute) at pressures up to 250 psi (17.2 bar). The datasheet describes a highly polished, annealed body with a 316 stainless-steel float and guide wire and states that it is acceptable in direct sunlight.

A strong one-piece acrylic rotameter for outdoor-rated panels

The F-550 differs from the polysulfone F-440 in body material and rating: the body is a single annealed acrylic moulding, the maximum working pressure is 250 psi at 70 F, and full-scale accuracy is plus or minus 5 percent. The scale is about 4 in (100 mm) long, giving easier reading than the 2 in scale of the F-440, and the meter is calibrated on water of specific gravity 1.0.

Nine range codes cover 1/4 in to 1 in male NPT adapters in polypropylene. The 005 model has a PTFE float; all others have a 316 stainless-steel float. Panel-mount versions are standard, with an adjustable (needle-valve) panel version available through the A suffix.

Key features as printed in the datasheet

• Range 0.025-20 GPM (0.1-75 LPM) in nine models.
• 250 psi (17.2 bar) at 70 F; 200 F (93 C) at 0 psi.
• Full-scale accuracy plus or minus 5 percent.
• Acceptable for direct sunlight exposure per the datasheet.
• 316 stainless-steel guide rod; float 316 SS or PTFE.
• Panel mount, with adjustable panel-mount (needle valve) versions.
• Polypropylene male NPT adapters, 1/4 to 1 in; FKM O-rings (EP optional).
• Maximum pressure drop 3 psi (manual).

Technical specification

General specification

Ranges

Dimensions, non-adjustable panel mount (A / B / C)

Materials

Selection and ordering guide

The code is F-55 [scale] L [A], for example F-55500L. Scale 250, 375, 376, 500 or 750 sets the range and 1/4 to 3/4 in male NPT adapter; 005, 010, 015 and 200 use 1 in adapters. L denotes the stainless-steel guide rod; add A for the adjustable panel-mount version, which the matrix lists for the 250 to 500 scales and the 750 to 200 scales separately.

Decide by pressure first. If the line exceeds 175 psi, or if the meter will be seen in sunlight, the F-550 is the better match than the F-440; if you need high temperature above 200 F, the polysulfone F-440 reaches 212 F.

Installation and operation notes

As with the F-440, the manual requires upward flow in a perfectly vertical pipe, with clean, uniform, supported piping, and threaded adapters make installation simple. Review system flow and pressure against the ratings before fitting, and check the pressure-versus-temperature graph for hot fluids because the 250 psi rating applies at 70 F.

Mount the panel version in a hole of the diameter shown in the dimension table, and calibrate expectations to clean water: the manual says the meter is tested and calibrated for clean water applications.

Applications in Oman and the GCC

The F-550 suits water, treated-water and chemical-feed lines in treatment plants where a local visual reading is needed at the point of use: RO permeate and concentrate indication, filter backwash flow, cooling-water circuits and skid-mounted dosing panels. Sunlight acceptability helps on outdoor panels, although fluid temperature must still be derated.

Gulf climates may heat standing water in a clear acrylic tube; the sheet provides the graph of temperature versus pressure and the 200 F fluid limit for guidance.

Selection and installation notes

A variable area flow meter is selected from the flow range, the liquid, the pressure and the connection. Mount it vertically with the flow upward, leave the straight lengths the maker advises, keep the tube clean, avoid pressure surges and fit a valve downstream to set the flow. Check that the scale is read at the top edge of the float as the manual shows.

Information needed for a quotation

Send the full model code, the quantity, the delivery location in Oman or the GCC, the intended use and any accessories needed, so that the complete package can be quoted together.

Documents and supply information

The manufacturer data sheet is attached to this page and should be read together with the project specification and the site risk assessment before a purchase is confirmed. Ratings, standards and dimensions are quoted as printed on that sheet. Lead time, stock position and certificates available with the shipment are confirmed in the quotation, and we supply to Oman and the wider GCC region for industrial, utility and building services projects.

Compatible accessories and related items

Related Blue-White items on this site include the polysulfone F-440 flow meter, the MS6 ultrasonic chemical-feed meter and the FLEXFLO and CHEM-FEED metering pumps; the F-550 manual and parts list are available on the manufacturer website.

Related Blue-White products: Blue-White MS6 SONIC-PRO Ultrasonic Chemical Feed Flow Meter.

Documents and quotation

For quotation, send your required quantity and destination. The Blue-White technical data sheet for F-550 is provided below the description on this page. Seven Star LLC works as an independent supplier from Muscat. Please compare code, ratings and approvals with the document before you place an order; see also the category listing.