Motor Speed Pumps for Cylinder Filling

These 1-inch motor speed pumps have long been popular for cylinder filling, small volume motor fueling and supplying small vaporizers. They offer the same heavy-duty construction of larger Blackmer models and are available in two mounting styles and capacity ranges. The LGF1 model is fitted with an integral bracket and coupling for direct flange mounting to a NEMA C-face motor. This bracket also allows the pump body to be rotated to simplify hookup to piping systems. The LGB1 model is equipped with a coupling and bracket for mounting to a conventional base. The LGF1 and LGB1 models will handle up to 10 U.S. gpm (38 lpm). The LGF1P and LGB1P models offer 50% greater capacity and will handle up to 15 U.S. gpm (57 lpm). All models have 1-inch NPT tapped ports and use an exclusive “combination” valve that acts as both a back-to-tank bypass valve and as an internal relief valve. This feature lowers installation costs by eliminating the need for a separate bypass valve. It also assures pressure relief if the back-to-tank bypass line is closed. The valve’s unique three-stage operation is shown in Figure 3. Standard construction materials for these models include Buna-N mechanical seals and Duravanes for handling both LP gas and anhydrous ammonia. Maximum differential pressure is 125 psi (8.62 Bar) for both models.	LG1/LG1P cutaway
	LGF1/LGF1P
	LGB1/LGB1P

Assembled Pump Units
LGF Drive Style
Flange Mounting - Direct Motor Drive
LGF1 and LGF1P models are supplied with an integral bracket and flexible shaft coupling, ready to accept a NEMA C-face motor. All LGF units are available with or without electric motors. Standard motors furnished by Blackmer for these pumps are explosion-proof, single-phase, 115/230 volt, with automatic reset overload protection. An explosion-proof manual switch is also available for mounting at the motor or remote location.

DM Drive Style
Bracket Mounting - Direct Motor Drive
LGB1-DM or LGB1P-DM base-mounted units are available, complete with pump, bracket, coupling and coupling guard, mounted on a common base, ready to accept a standard NEMA motor. All DM units are available with or without electric motors.

Selection Data
When selecting a standard pump or assembled unit from the table below, check the pump’s delivery and brake horsepower requirements in the performance curves. These pumps are rated for continuous duty, although such applications may accelerate pump wear rates, particularly if vaporization occurs in the pump intake line. Pumps used on vaporizers should be mounted with inlet up, and sized for a capacity of at least 150% of the normal peak load to prevent system failure due to sudden pressure drop on start-up. Additional system requirements can be achieved by series of parallel staging.

Normal Operation Valve is completely closed during normal operation with discharge line open.	Back-to-Tank Bypassing Discharge pressure exceeding the valve setting opens valve to second stage, returning all or part of pump flow back to supply tank.	Pressure Relief If back-to-tank line is closed, valve opens to third stage, passing flow back to inlet side of pump.

click table to see larger

¹ Check the pump’s delivery and brake horsepower requirements in the performance curves below. See footnote with the curves which explains the factors that can cause delivery to vary.
² Motors may be specified from dimension charts below and Electric Motor Price List No. 10-MTRG-01 (explosion-proof manual start switch for 1 & 1-1/2 horsepower single-phase motors also available).
³ Maximum rated working pressure is 350 psi (24.13 Bar) for LPG and NH3 (limited by U.L. and N.F.P.A. 58).
⁴ Pump flange accepts NEMA C-face motors with 5-7/8" bolt circle diameter. Pump flange will not accept 182TC or 184TC frames.

Performance Curves
These curves are based on approximate delivery rates when handling propane or anhydrous ammonia at 80°F (26.7°C). Line restrictions such as excess flow valves, elbows, etc. will adversely affect deliveries. For propane at 32°F (0°C), actual delivery will be further reduced to about 80% of nominal. Delivery of butane at 80°F (26.7°C) will be 60% to 70% of these values, and may run as low as 35% to 45% at 32°F (0°C). This loss of delivery is not a pump characteristic but is caused by natural thermodynamic phenomena of liquefied gases.