F56 Metal Tube Variable Area Flowmeter

LORRIC's F56 metal tube variable area flowmeter delivers non-contact, magnetic-coupled flow indication from DN15 to DN250, for liquid, gas, and steam service. Choose local mechanical, battery-powered LCD, or 4-20mA/HART remote output on the same measuring tube — with wetted materials from 316 stainless to Hastelloy, titanium, zirconium, and PTFE lining, and Exi/Exd explosion-proof options for hazardous areas.

Nominal size:	DN15–DN250 (1/2"–10")
Media:	Liquid, gas, steam
Wetted materials:	304/316/317 SS, PTFE-lined,
	Hastelloy, Ti, Zr, PP, PV, Al, Cu
Measuring range:	10–300,000 L/h (water)
	0.7–3,000 Nm³/h (air)
Turndown ratio:	10:1
Accuracy:	1.0 / 1.5 / 2.0 / 2.5 (% F.S.)
Max pressure:	Up to 42 MPa (size-dependent)
Fluid Temp:	Standard: -80~300°C
	High-temp option: up to 400°C
Enclosure rating:	IP67
Output:	Local needle or LCD
	4-20mA / HART (remote models)
Explosion-proof:	Ex ia IIC T4/T5/T6 Ga · Ex d IIC T6 Gb

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Metal Rotameter

A rotameter measures flow by how high a float rises inside a tapered tube — the higher it rises, the more flow is passing through. The F56 uses a metal tube instead of plastic or glass, built for higher pressure, higher temperature, and harsher conditions. A permanent magnet embedded in the float lets the indicator read its position straight through the metal wall, driving the needle on the dial and, on digital models, updating the LCD with instantaneous and total flow

Rated accuracy you can count on

The F56 comes in four accuracy grades — 1.0, 1.5, 2.0, or 2.5 . Which checks the meter's error at 10 points across the scale, from 10% up to 100% of full flow, not just at one reading. That matters because accuracy on a rotameter is stated as a percentage of the meter's full-scale range, not of whatever it happens to be reading — so the same meter is more accurate near the top of its range than near the bottom. We'll help you pick a scale where your everyday flow sits comfortably in the upper half, so you get the accuracy you paid for in daily use — not just at maximum flow.

Built for extreme heat and pressure

Whether your line runs near-freezing utility water or scalding process fluid, there's an F56 built for it. Standard models cover a wide temperature range as-is, and an optional high-temperature configuration extends that up to 400°C for direct steam service. Pressure ratings scale with pipe size too, holding firm even at the high-pressure end where a lighter-built flowmeter would give out. Exact ratings for your size, material, and indicator type are in the Specs tab.

Materials Matched to Your Process

Every F56 shares the same measuring principle — what changes is what touches your fluid. Pick the wetted material based on what's actually flowing through the line:

Stainless steel

304 and 316 cover most installations — 316 adds resistance to chlorides and mild acids. Low-carbon "L" grades resist weld-seam corrosion, the standard for food, beverage, and pharma lines.

PTFE lining

A fully inert lining protects against strong acids and alkalis that would attack bare stainless steel — for aggressive chemical service.

Hastelloy, titanium & zirconium

For hot acids, caustic soda, seawater, and the most aggressive chemical service — where even 316 stainless would corrode.

PP & PV

A lighter, lower-cost build for mild-duty utility water or dilute chemical dosing at ambient temperature (vertical mounting, up to DN100).

Choose the Connection that Fits Your Line

Two connection options available:

Flange connection is the standard choice for permanent, high-pressure process piping.
Tri-clamp sanitary connection lets the meter come apart for cleaning in seconds, no bolts involved. Suitable where hygiene and quick disassembly matter more such as food, beverage, and pharma lines.

Mount it however your piping runs

Not every installation has room for a straight vertical run, so the F56 mounts five different ways — vertical, horizontal, and three side/bottom-entry variants for tight spaces. Whichever orientation fits your existing layout, the same measuring tube and indicator options apply.

Calibrated to your fluid, not just water

Look closely at the dial and you'll see three small lines under the digital display — the density, temperature, and pressure the printed scale was actually calibrated against. A float rides differently in a light gas than in a dense liquid, so we compute each meter's scale from your real operating fluid — not a generic water or air reference — so the numbers on the dial match what you're actually measuring, right out of the box.

Choose How You Read the Flow

Every F56 measures the same flow on the same tube — what changes is how you want to see it: a local needle only, a two-wire signal to your control system, or a battery-powered display, each suited to a different job site.

Simple local reading — P8

No wiring, no power. A polished stainless dial and mechanical needle give you a clear flow reading right on the pipe — ideal for sanitary areas or anywhere you just need to see the flow.

Tie it into your control system — P10

Keeps the local needle and adds an LCD plus a loop-powered 4-20mA/HART output, so flow reaches your DCS or PLC over two wires. Available intrinsically safe or flameproof, with optional alarm switches.

Hazardous-area ready — P10I

A flameproof local needle display for sites that need Ex-rated protection without a remote signal. Add a switch and it can also trip a flow alarm at the meter.

F56 P10B battery-powered indicator with LCD

No power line? No problem — P10B

Runs on a single lithium battery for about a year, and still gives a full LCD readout of flow and totals — wherever the installation happens to be.

Specifications

Specification		Value
Model		F56
Media		Liquid, gas, steam
Measuring range*	Water	10–300,000 L/h
Measuring range*	Air	0.7–3,000 Nm³/h
Turndown ratio		10:1
Accuracy class**	Local needle (P8)	1.0, 1.5, 2.0, 2.5
	Local digital, battery (P10B)	1.0, 1.5, 2.0, 2.5
	Remote, needle + digital (P10/P10I)	1.0, 1.5, 2.0, 2.5
Media temperature***	Local needle (P8)	-80°C to +300°C (PTFE lining: 0–80°C)
Media temperature***	Digital & remote (P10, P10B, P10I)	-40°C to +120°C (PTFE lining: 0–80°C)
Ambient temperature	Local needle (P8)	-40°C to +120°C
Ambient temperature	Digital & remote (P10, P10B, P10I)	-20°C to +60°C
Media viscosity (excl. F56/SP)		DN15: <1 mPa·s (F15.00–F15.03), <5 mPa·s (F15.04–F15.30) · DN25: <20 mPa·s · DN50–DN250: <30 mPa·s
Nominal pressure	DN15–DN50	4.0 MPa (max: DN15/DN25 42 MPa, DN50 32 MPa)
Nominal pressure	DN80–DN250	1.6 MPa (max: DN80 10 MPa, DN100 6.4 MPa, DN125/DN150 4.0 MPa, DN200/DN250 2.5 MPa)
Process connection		Flange (DIN2501 / ANSI / JIS — DIN recommended); sanitary tri-clamp, threaded, and compression fitting available to order
Electrical connection		M20×1.5, 1/2"G, 1/2"NPT, 3/4"G, 3/4"NPT
Mounting orientations		Vertical, horizontal, top-in bottom-out (vertical lines), bottom-in side-out, side-in side-out
Straight pipe run		Inlet ≥5×DN · Outlet ≥250 mm
Enclosure rating		IP67
Explosion-proof rating		Ex ia IIC T4/T5/T6 Ga (intrinsically safe) · Ex d IIC T6 Gb (flameproof) · Certificate CE16.1206X
Intrinsic safety parameters		Ui=28V, Ii=93mA, Pi=0.65W, Ci≤5nF, Li=0mH (barrier: Uo≤28V, Io≤93mA, Po≤0.65W, Co≥Ci+Ccable, Lo≥Li+Lcable)
Output signal		2-wire (4-20)mA / HART protocol

* Measuring range shown at reference conditions: clean water at 20°C, air at 20°C / 0.1013MPa absolute; special ranges available on request.
** Accuracy class is verified per the German VDI/VDE 3513 standard at 10 points across the scale (10%–100% of full flow). Since accuracy is stated as % of full-scale reading, real-world accuracy is best when normal operating flow sits in the upper half of the selected range.
*** A high-temperature option (H1/H2/H3 order codes) extends media temperature up to 400°C on any indicator type — specify at order time.

Product Size

All mounting forms accept any indicator type (P8/P10/P10I/P10B) on the same measuring tube.

Vertical Mounting

F56 vertical mounting dimension drawing

Unit: mm

DN	H	L	L1
DN15	250	156	75
DN20	250	162	80
DN25	250	165	84
DN32	250	171	90
DN40	250	177	95
DN50	250	180	98
DN65	250	187	106
DN80	250	194	112
DN100	250	203	122
DN125	400	213	131
DN150	400	225	145
DN200	450	245	170
DN250	450	253	183

Side-In / Side-Out Mounting

F56 side-in side-out mounting dimension drawing

Unit: mm

DN	H	H1	B
DN15	200	500	100
DN20	200	500	100
DN25	200	500	100
DN32	200	500	100
DN40	250	600	120
DN50	250	600	120
DN65	350	700	160
DN80	350	700	160
DN100	350	750	180
DN125	400	800	250
DN150	450	850	250

Bottom-In / Side-Out Mounting

F56 bottom-in side-out mounting dimension drawing

Unit: mm

DN	H	H1	B
DN15	200	500	100
DN20	200	500	100
DN25	200	500	100
DN32	200	500	100
DN40	250	600	120
DN50	250	600	120
DN65	350	700	160
DN80	350	700	160
DN100	350	750	180
DN125	400	800	250
DN150	450	850	250

Horizontal Mounting

F56 horizontal mounting dimension drawing

Unit: mm

DN	H	H1
DN15	200	255
DN20	200	255
DN25	200	255
DN32	250	250
DN40	250	245
DN50	250	245
DN65	300	255
DN80	350	270
DN100	350	280
DN125	400	415
DN150	450	440
DN200	500	520

P8 Local Indicator — Standard Dimensions

F56 P8 indicator dimension drawing

Unit: mm

DN	H	L	L1
DN15	250	87	69
DN20	250	93	74
DN25	250	96	78
DN32	250	102	84
DN40	250	108	89
DN50	250	111	92
DN65	250	118	100
DN80	250	122	107
DN100	250	128	116
DN125	400	133	126
DN150	400	139	140
DN200	450	150	165
DN250	450	155	178

Flange Bolt Pattern (ANSI B16.5 / DIN2501)

F56 flange bolt-circle dimension diagram

Unit: mm

Size (ANSI B16.5, 150lb)	D	k	b	d3	f	n	d2
1/2"	88.9	60.5	11.2	35.1	1.6	4	15.7
3/4"	98.6	69.9	12.7	42.9	1.6	4	15.7
1"	108.0	79.2	14.2	50.8	1.6	4	15.7
1-1/4"	117.3	88.9	15.7	63.5	1.6	4	15.7
1-1/2"	127.0	98.6	17.5	73.2	1.6	4	15.7
2"	152.4	120.7	19.1	91.9	1.6	4	19.1
2-1/2"	177.8	139.7	22.4	104.6	1.6	4	19.1
3"	190.5	152.4	23.9	127.0	1.6	4	19.1
4"	228.6	190.5	23.9	157.2	1.6	8	19.1
5"	254.0	215.9	23.9	185.7	1.6	8	22.4
6"	279.4	241.3	25.4	215.9	1.6	8	22.4
8"	342.9	298.5	28.4	269.7	1.6	8	22.4
10"	428.4	362.0	30.2	323.9	1.6	12	25.4

DN / PN (DIN2501)	D	k	b	d3	f	n	d2
15/4.0	95	65	16	45	2	4	14
20/4.0	105	75	16	55	2	4	14
25/4.0	115	85	18	68	2	4	14
32/4.0	140	100	18	76	2	4	18
40/4.0	150	110	18	86	2	4	18
50/4.0	165	125	20	102	3	4	18
65/1.6	185	145	18	120	3	4	18
80/1.6	200	160	20	138	3	8	18
100/1.6	220	180	20	162	3	8	18
125/1.6	250	210	22	188	3	8	18
150/1.6	285	240	22	218	3	8	22
200/1.6	340	295	24	268	3	12	22
250/1.6	405	355	26	325	3	12	26

Tri-Clamp / Sanitary Connection

F56 tri-clamp sanitary connection dimension drawing

Unit: mm

DN	D	P	L	L1
DN15	34.0	27.5	156	75
DN20	34.0	27.5	162	80
DN25	50.5	43.5	165	84
DN32	50.5	43.5	171	90
DN40	50.5	43.5	177	95
DN50	64.0	56.5	180	98
DN65	91.0	83.5	187	106
DN80	106.0	97.0	194	112
DN100	119.0	110.0	203	122

F56 flowmeters are put to work across oil & gas, chemical, metallurgy, power, food & pharmaceutical, and pulp & paper processes — measuring and controlling liquid, gas, and steam flow wherever the line demands.

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