Gear Pump for Asphalt

Asphalt cement, polymer-modified bitumen, asphalt emulsion and pitch can all fall within the FBE series, but on different rows of the speed table. What decides is the viscosity at the temperature at which the product will be pumped and at the lowest temperature it can reach at startup, together with flow, pressure and suction. The 2026 FBE catalogue lists the FBE for pumping asphalt in refineries and publishes, for the series, viscosity from 30 to 100,000 SSU, discharge pressure up to 22 kgf/cm² and a maximum speed of 1,750 rpm (p.3). In the FBE, two external gears turn inside the casing: the fluid fills the cavities between the teeth and the casing, is carried around the periphery to the discharge, and the meshing prevents return to suction (2026 FBE catalogue, p.2). With a viscous binder, this has two consequences for selection: speed must drop as viscosity rises, and the pump needs overpressure protection, covered below.

• Complete product designation, with additives and polymers, and the safety data sheet.
• Viscosity with its method and measuring temperature: Saybolt Furol, rotational or kinematic.
• Viscosity–temperature curve, or at least two points: pumping and startup.
• Specific gravity (g/cm³) at pumping temperature, to convert cP to cSt.
• Maximum process temperature and the lowest the product can reach in an idle line.
• Particles, if any: the MTEC-01/01 manual requires consulting FB for suspended solids (item 2.3).

The FBE speed table is in SSU, and a binder test report rarely uses that unit. Viscosity may come in Saybolt Furol seconds (SSF), by the ABNT NBR 14950 method for bituminous materials; in cP, from viscosity at elevated temperatures with a rotational viscometer (ABNT NBR 15184 and ASTM D4402); or in cSt (mm²/s), from kinematic viscosity, which ASTM D2170 measures on asphalt binder at 135 °C. The 2026 FBE catalogue (p.5) gives all three steps. From dynamic to kinematic viscosity: cSt = cP ÷ specific gravity (g/cm³). From kinematic viscosity to SSU, above 300 SSU: SSU ≈ cSt × 4.635. From a Saybolt Furol reading to SSU, the viscometer factor is 10. These are approximate conversions at the same temperature; a unit conversion does not carry viscosity to another temperature. If the report gives viscosity at 135 °C and the pump will run at another temperature, ask the supplier for the viscosity–temperature curve instead of extrapolating.

• Example 1 (hypothetical figures): 300 cP at pumping temperature and a specific gravity of 0.95 give about 316 cSt and 1,460 SSU. Row 250 to 2,500 SSU: 1,150 rpm, direct drive, FBE 1/8″ to 5″.
• Example 2 (hypothetical): at startup, the same binder, colder, measures 2,000 cP with a specific gravity of 0.97: about 2,060 cSt and 9,560 SSU. Row 7,500 to 10,000 SSU: 700 to 500 rpm, with pulley or reducer, FBE 1.1/2″ to 6″.
• Example 3 (hypothetical): a reading of 60 SSF gives about 600 SSU, in the 250 to 2,500 SSU row.
• Ranges and sizes for each row: speed table in the 2026 FBE catalogue, p.5.

The most viscous condition governs. In example 2, the binder reaches about 9,560 SSU at startup; selected for that condition, the FBE falls in the 700 to 500 rpm row, with a pulley or reducer, even if the product stays near 1,460 SSU in normal running. The other option is to start only once the product is heated, which is the role of the CA chamber. FB supplies the FBE with direct drive to an electric motor or to a gear motor, both on a metal baseplate with a flexible coupling (2026 FBE catalogue, p.4). Power rises with viscosity, because friction increases absorbed power, and the net positive inlet pressure required (NPIPR) also rises (Hydraulic Institute). The catalogue (p.5) gives efficiency η by viscosity and pressure; with flow Q in m³/h and pressure Δp in kgf/cm², shaft power is P (cv) = Q × Δp ÷ (27 × η), where cv is metric horsepower. Hypothetical example: 8 m³/h and 7 kgf/cm² at 9,560 SSU. Between the 9,000 and 10,000 SSU columns, the more viscous one gives the lower efficiency, η = 0.25, and the safer result: 8 × 7 ÷ (27 × 0.25) ≈ 8.3 cv. With the 25% reserve for the 6 to 10 cv band, the commercial motor must have at least 10.4 cv.

• Efficiency η at 3 kgf/cm²: 15% at 10,000 SSU, 11% at 30,000 SSU, 10% at 50,000 SSU and 9% at 100,000 SSU (2026 FBE catalogue, p.5).
• Efficiency η at 7 kgf/cm²: 25% at 10,000 SSU, 20% at 30,000 SSU, 17% at 50,000 SSU and 14% at 100,000 SSU (2026 FBE catalogue, p.5).
• Efficiency η at 15 kgf/cm²: 35% at 10,000 SSU, 30% at 30,000 SSU, 28% at 50,000 SSU and 25% at 100,000 SSU (2026 FBE catalogue, p.5).
• Motor power reserve: 50% up to 2 cv, 30% from 3 to 5 cv, 25% from 6 to 10 cv, 15% from 11 to 25 cv and 10% above 25 cv (2026 FBE catalogue, p.5).
• The selection table on p.6 applies to viscosity below 1,000 SSU, with power at the pump shaft (BHP); for a viscous binder, power comes from η.

In the MTEC-01/01 manual's nomenclature, CA means with heating chamber, and the letter A indicates the larger-diameter gear; CA-A combines both (item 1.2). The chambered variant starts at 1.1/2″ (2026 FBE catalogue, p.6 and p.7; MTEC-01/01, Table 1), and the catalogue's selection table also lists the FBE 10″ CA STD (p.6). In the cross-section of the FBE 1.1/2″ to 4″ with chamber (Figure 8 and Table 14), the casing comes with the chamber built in (part 102.4), with gaskets between covers, plugs and casing, packing with a gland and four bushings; the FBE 1.1/2″, 3″ and 4″ M6 CA also carry four flow reducers (part 456). The chamber's inlet C1 and outlet C2 are 3/8″ BSP on the FBE 1.1/2″ and 1/2″ BSP on the 2″, 3″ and 4″, where no interconnection is supplied (Table 17), and Figure 13 of the manual shows the flow direction. The 2026 FBE catalogue (p.5) notes that the A, CA and CA-A variants apply only to models available in the current line, and that the FBE 1/2″ A is no longer supplied.

• Available heating fluid, with temperature and pressure.
• Chamber interconnection: supplied with the assembly or made on site through connections C1 and C2.
• How the product temperature inside the pump will be checked before startup.
• On the FBEI, the chamber is a 2026 catalogue accessory (p.4), and manual MAN001-10 limits the jacket to steam up to 185 °C and thermal fluid up to 232 °C, at up to 10 bar.

Because the meshing prevents return to suction, overpressure protection is part of the assembly. The 2026 FBE catalogue lists the internal relief valve among the accessories, in brass or AISI 304 stainless steel (p.3); in the MTEC-01/01 manual, it is a ball-and-spring valve with an adjusting screw and nut, using cover part 163 for the valve (Figure 10 and Table 16). The FBEI manual (MAN001-10) says not to use the relief valve to control pressure or flow, not to run with it open for long periods and, on a pump without a valve, to install another protection system, such as a line valve, pressure switch or torque limiter. Before startup, the same manual calls for feeding the heating jackets gradually, to avoid thermal shock, turning the shaft by hand and starting only with the fluid inside at suitable temperature and viscosity. With the FBE CA, ask FB for the startup and restart criteria of the supplied assembly.

The 2026 FBE catalogue offers packing, mechanical seal or lip seal (p.3). In the MTEC-01/01 manual, the packing is compressed by a gland adjusted with a hex nut, and the standard mechanical seal is type 21, in ceramic × graphite × Viton, with an AISI 304 stainless steel spring (items 2.4 and 2.5). The choice follows from the temperature, the binder's composition and the leak containment required. FBE shafts turn in bushing bearings, and the catalogue lists self-lubricating bronze, cast iron, PTFE (Teflon), graphite and babbitt (p.3). A rolling bearing exists only in the external bearing, which is an accessory (p.3; Figure 9 and Table 15). The seal housing drain, measuring instrument, seal flush and seal quench points, all 1/4″ NPT, are made only according to the application and at the customer's request (Table 17).

Unloading, tank-to-tank transfer, recirculation and process feed are different duties, each with its own flow, pressure, suction and temperature. Each point goes through the SSU conversion, the speed-table row and the power calculation, and the assembly chosen for one point is not automatically repeated at the others. The asphalt, bitumen and pitch application page describes the pumping points of a plant and the heating strategies. Also separate the pump that transfers the binder from the pump that circulates the heating thermal oil: they are different circuits and duty conditions. The 2026 FBOT catalogue states that the FBOT thermal oil series can be used in asphalt plants (p.2).

FB manufactures the FBE and FBEI in Cabreúva, Brazil, and the catalogues and manuals cited in this guide are listed in the sources at the end of the page. The MTEC-01/01 manual records a hydrostatic test of 10 kgf/cm² (Table 5), and FBE ports are BSP threaded from 1/8″ to 1″ and ANSI B16.5 150 lb flanged from 1.1/2″ upward (2026 FBE catalogue, p.6). Several FBE models are kept in stock, and the availability of each is given in the quotation. For replacement, the catalogue lists as spare components the drive and driven shafts, the drive and driven gears, bushing sets, covers, the packing gland and its nut, the lip seal, the mechanical seal and the relief valve (p.4). For a binder beyond the FBE range, compare the FBEI: the 2026 FBEI catalogue describes it as ideal for transferring high-viscosity liquids (p.3), with the standard series driven by a reducer at low speed and viscosity up to 140,000 cP (p.4). Since cP is dynamic viscosity, convert it with the specific gravity before comparing with the FBE table in SSU.

• Binder: designation, technical data sheet and safety data sheet.
• Viscosity at pumping and at startup, with method, temperature and specific gravity.
• Flow, discharge pressure and suction condition for each point.
• Available heating: thermal oil or steam, and the desired control.
• Preferred sealing and leakage restrictions.
• Replacement: nameplate, complete code with the variant (CA, CA-A) and available drawing.