Here you can find all of the technical bulletins issued by Tri-Rotor.  Issued periodically, these bulletins help distributors and customers alike to learn more about Tri-Rotor pumps and information related to application, performance, and helpful maintenance tips.  In addition, you’ll find new product releases touted here.

Original Tri-Rotor Technical Bulletin Releases:

Tri-Rotor Pumper No 4 – Determination of Pump Horsepower

Tri-Rotor Pumper Issue No 4 Determination Of Pump Horsepower The data below is based on conservative figures.  Nevertheless, these are compromises which have been proven safe over the years.  For pumps equipped with solid heads (for simple transfer applications) or bypass heads (with integral relief valve), the only penalty incurred would be the possibility of computing the next larger horsepower motor than required.
1. Select RPM (pump shaft speed) from Pumper Issue No. 3.  NOTE:  Pump displacement factor given in “GALLONS/100 REVOLUTIONS,” from which determine GPM (pump discharge rate).
2. In above formula use M.E.’s [Mechanical Efficiency] as follows:
5,000 10,000 15,000 20,000 30,000 40,000 50,000 75,000 100,000
50 42 38 35 31 29 27 25 20

3. Selection of above calculated horsepower should be made within the limits below:
PUMP SERIES 20 40 80,100,120 200,220
1/3 3/4 2 5
3 5 10 25

*TOTAL PRESSURE for the solid or bypass style pump is the maximum pumping pressure PLUS 20 PSI additional for external or internal relief valve setting.  Tri-Rotor pumps equipped with the exclusive “V-Head” (variable volume) use ONLY the maximum pumping pressure for the TOTAL PRESSURE.

Please see Tri-Rotor Pumper Issue No 4 for further details and a calculation example.

Tri-Rotor Pumper No 3 – Viscosity-Speed-Gallonage (VSG) Relationship

Tri-Rotor Pumper Issue No 3 Viscosity-Speed-Gallonage (VSG) Relationship Liquid viscosity limits the speed at which a positive displacement pump may be run.  The more viscous the pumpage is, the slower the allowable pumping rate, for a given pump size.

Materials of construction, clearances between moving parts, port size and configuration, and various other factors also help determine the maximum allowable running speed.  For example, depending upon type of metals used, and physical size of the pumping members, the pump should not be speeded beyond the allowable rubbing feet per minute of the mating parts surfaces.  Generally these factors are controlled through engineering and production within the pump manufacturing plant.

Viscosity of the fluid to be pumped is an element outside the pump factory control.  The pump engineer must take this liquid characteristic into consideration when fitting the pump to a given application.

The No 3 issue of the Tri-Rotor Pumper provides a much deeper dive into the viscosity-speed-gallonage relationship for all series of Tri-Rotor pumps.  You’ll also see a VSG chart for maximum recommended pump speeds for various viscosities for all the series as well.

Tri-Rotor Pumper No 2 – Pump and System Analysis Sheet

Tri-Rotor Pumper Issue No 2 Pump And System Analysis Sheet Figuratively and actually the heart of a system is its pump.  For so vital a role, this necessitates careful selection; else the system will not be a success.

We manufacture the Tri-Rotor pump, a positive displacement (PD) class, featuring a unique rotary piston design, in a wide range of sizes, material and construction configurations and internal modifications to satisfy almost every application requiring a PD class pump.

The engineer in need of a pump must provide us with some rather exacting information.  Four items are particularly essential for:

Selecting the Pump
GPM (Gallons Per Minute)   Flow rate (GPM) required establishes the model pump size, its shaft speed, and port size.
VIS – Viscosity (SSU/cPs)   Nature and composition of the pumpage, most importantly the viscosity (VIS), also enter into determination of shaft speed, pump size, etc. as well as dictating pump make-up (pH, temperature, et al, call out materials of construction).
PSI (Lbs. Per Sq. In.)   We adjust relief valve setting based on total pumping pressure (PSI/TDH) of the system, which in turn enables us to calculate horsepower of motor to be used, and so on.
Type of Head   Our competitors furnish only two alternative pump variations per model, solid head for simple transfer service, or bypass head, (we call ours “X-Head”) incorporating an integral relief valve for system protection.  Tri-Rotor users enjoy a third choice – the “V-Head,” providing automatic variable control of volume or pressure, multi-viscosity capability, remote and/or computer feedback governing, all at constant pump shaft RPM.
Inserting the above essentials into Pumper Issue Nos. 3 & 4, we, or our user, easily targets the Tri-Rotor pump model for the application.
Mounting Pump with Motor and Drive
Type of Drive   Tri-Rotor can do it all, in house, with rugged design mounts, bases, risers, chain couplings, arc guards, and V-Belt drives.  Style “M” designates direct connected integral or gearhead motor drive.  Style “SM” uses gearmotor drive, “CFM” incorporates a “C” Flanged adaptor.  For footed double shaft enclosed helical gear reducer drive, Style “GR” or “SGR” (in-line).  Style “BD” indicates belt driven.
Type of Motor   Available from stock are standard horizontal motors from 1/3 HP to 25 HP, 1140 RPM and 1725 RPM in Single and Three phase, 60 Hertz in popular Voltages and NEMA frame sizes.  Where low pump shaft speeds are required, we carry a wide range of gearhead and gearmotor drives.
For submitting the above information, we provide our Pump and System Analysis Sheet in Tri-Rotor Pumper No 2.  Make copies, fill out, and fax back to us.  We’ll respond with recommendations and formal quotation in 24 hours.

Tri-Rotor Pumper No 1 – ???

So what ever happened to Pumper No 1?  No one knows for sure.  We’ve searched high and low but alas, no luck so far.  Maybe someone out there has a copy.  Please let us know if you do and we’ll give you some sort of Tri-Rotor trinket (with some blatant advertising included)!