ViscoTwin Options - PROCESSTEC

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ViscoTwin Options

The ViscoTwin screw pump provides a range of options that allow adaption to many different situations. Please contact us if your needs are different and the options you are looking for do not appear below.
Process Connections
Product Description
Max Rev
Pump Face
Pump Housing
ViscoTwin 70.22
0.019 Gal/Rev
4,000 rpm
3.0” OD
2.5” OD
ViscoTwin 70.29
0.025 Gal/Rev
4,000 rpm
3.0” OD
2.5” OD
ViscoTwin 70.43
0.037 Gal/Rev
4,000 rpm
3.0” OD
2.5” OD
ViscoTwin 104.27
0.043 Gal/Rev
3,600 rpm
4.0” OD
3.0” OD
ViscoTwin 104.36
0.057 Gal/Rev
3,600 rpm
4.0” OD
3.0” OD
ViscoTwin 104.53
0.084 Gal/Rev
3,600 rpm
4.0” OD
3.0” OD
ViscoTwin 130.33
0.084 Gal/Rev
3,000 rpm
5.0” OD
5.0” OD
ViscoTwin 130.44
0.112 Gal/Rev
3,000 rpm
5.0” OD
5.0” OD
ViscoTwin 130.65
0.164 Gal/Rev
3,000 rpm
5.0” OD
5.0” OD
Visco Twin
Options for 3A or EHEDG

All ViscoTwin pump models are designed according to 3A and EHEDG guidelines. General design and detail design considerations like radii, O-ring grooves, surface treatment, material, and elastomer selection fulfill both norms.
Only pumps for the US dairy industry require the 3A symbol attached to it. The only difference is a slight improvement on the spindle polish. In case the spindles are hardened with the kolsterization process, the spindles show a matte surface, because the spindle polishing took place before the kolsterization process.
All ViscoTwin Pump Housings are hardened with a DURALOY treatment. The inside surface of the pump housing is always matte.

The general build of all ViscoTwin pumps also fulfills OSHA and CE guidelines.
Pump Face Options
NPSH Optimized Pump Face
Designed to transition pumped product more efficiently and gently between the Intake Pipe and the Pump Housing
Dual Port Pump Face
Allows for two lines to conjoin at the pump which reduces piping system complexity, while also maintaining efficiency.
Eco Pump Face
An Economic option pumping less viscous or more robust product that can withstand rapid pressure changes and turbulent flow.
Pump Face Port Size Options:
ViscoTwin70: 2” to 3”
ViscoTwin104: 2.5” to 4”
ViscoTwin 130: 3” to 6
Process Connection Options
An assortment of Process Connection options are available in a variety of sizes to fit your specific needs
Tri Clamp
DIN 11851
(Outside Threaded)
DIN 11864-1
(Screwed Union)
DIN 11864-2
(Flange Union)
DIN 11864-3
(Clamp Union)
Varivent Flange
Butt Weld
Pump Housing Options
These lightweight cast ViscoTwin Pump Housings feature DURALOY hardening, and are designed to allow Pump Housing Ports up to 5” in diameter.

Pump Housing Port Size Options:
ViscoTwin70: 1.5 to 2.5”
ViscoTwin104: 2” to 3”
ViscoTwin 130: 2.5” to 5”
Process Connection Options
An assortment of Process Connection options are available in a variety of sizes to fit your specific needs
Tri Clamp
DIN 11851
(Outside Threaded)
DIN 11864-1
(Screwed Union)
DIN 11864-2
(Flange Union)
DIN 11864-3
(Clamp Union)
Varivent Flange
Butt Weld
Elastomer Options
All Available ViscoTwin Elastomer Options are listed in the table below.

140° C
28 bar
120° C
28 bar
200° C
40 bar
200° C
50 bar

Spindle Options
Three different spindle pitches are available for each ViscoTwin pump size, in any combination of Standard, Hardened, or Hardened Tapered and your choice of EHEDG or 3A.
Smaller spindle pitches are used to create high discharge pressures, especially with product at viscosities below 2000 cps, at the cost of limiting the flowrate.
Larger spindle pitches can be used for high-viscous product at medium discharge pressure, and/or high flowrates of low-viscous media like CIP at lower differential pressures.
For product with specific particulate sizes, the spindle pitch will determine the minimum pump size. For example, if the particulate requires a cross section of 1”, then the pump would need to be a Model 104.53 or Model 130.65
Mechanical Seal Options
Different Mechanical Sealing Surfaces and Elastomers are available for the ViscoTwin pumps. Material and design are selected based on application. Processtec has mechanical seals for various pressure and temperature requirements available.
For easy handling, the ViscoTwin designed to use a fully pre-assembled cartridge seal to prevent assembly errors and damages to the sealing surfaces.
Single Acting Mechanical Seals (SAMS)
ViscoTwin NG Pumps with Single Acting Mechanical Seals CANNOT run dry. Due to the self draining capability of ViscoTwin NG Pumps, Processtec strongly recommends this type of seal in select applications where the pump never runs dry or without product, such as transfer pumps.
Sealing Surface:
- Silicon Carbide (SIC)
- Tungsten Carbide (TC)
- Tungsten Carbide Knife Edge (TCKE) (Standard)
Double Acting Mechanical Seals (DAMS)
ViscoTwin Pumps with Double Acting Mechanical Seals can run dry as long as the quench media flows through the seal. The quench media lubricates and cools the sealing surfaces whether there is product in the pump or not.
The quench media reduces friction between the rotating sealing surface and the static sealing surface. Processtec, as a default, installs water flush seals with Tungsten Carbide Knife Edge for exceptional longevity results – so far, we have not had one DAMS failure!
Sealing Surface:
Silicon Carbide (SIC)
Tungsten Carbide (TC)
Tungsten Carbide Knife Edge (TCKE) (Standard)
Bearing Housing Options
ViscoTwin pumps are unique in that they use 4 Angular Ball Bearings to absorb the axial forces in both directions. The Standard arrangement is 2:2. For High Pressure applications, we configure a 3:1 (shown below) or 1:3 arrangement, depending on flow direction. Only the ViscoTwin has 4 bearing slots, allowing for these kinds of arrangements, while other brands have 3 bearing slots only
High Pressure / High Temperature Options
The standard mechanical seals are designed to withstand a product area pressure of up to 400 psi. With High Pressure Seals, the product area pressure can reach up to 650 psi.
These seals are only available in a specially designed HPHT (High Pressure, High Temperature) ViscoTwin, which can be built to withstand temperatures of up to 380 degrees Fahrenheit!
Please contact Processtec for more information on our High-Pressure pumps.
CIP Options
The Available CIP Options for use with Processtec’s ViscoTwin pumps are outlined below.
Self-Propelled Cleaning (CIP)
The pump is used as a CIP return pump. This is mostly the case when a pump is installed as a tank discharge pump. The Max Flowrate is according to the pump curve for viscocity 1 cps.
Inline Cleaning (CIP)
Max Flowrate depending on differential pressure only. The pump does not need to propel the CIP solution and is part of the cleaned pipe line. A dedicated CIP pump upstream is propelling the CIP solution.
Motor Options
Four ViscoTwin pump motors are optimized to deliver max torque in the 300 to 1200 rpm range at the lowest performance requirement to save cost & complexity. Above 1200 rpm’s the ViscoTwin pump motor can be used to boost CIP & water, as low viscous media doesn’t require high torque. In order to use the motor at higher rpm’s, the VFD must be set to allow spin over 60 Hz. Most modern motors from reputable manufacturers can handle the 3600 rpm’s, as the shaft & bearings from 4-pole + motors are typically the same as their 2-pole counterparts.
Sample with 7.5kW (10hp) Motor
SPEED @ 50Hz
SPEED @ 60Hz
2-Pole Motor
2900 rpm
25 Nm/18 lb-ft
3500 rpm
20 Nm/15 lb-ft
4-Pole Motor
1450 rpm
49 Nm/35 lb-ft
1750 rpm
41 Nm/30 lb-ft
6-Pole Motor
965 rpm
74 Nm/55 lb-ft
1166 rpm
61 Nm/45 lb-ft
8-Pole Motor
725 rpm
99 Nm/73 lb-ft
875 rpm
82 Nm/60 lb-ft

Gearmotors are selected when higher torque is needed at lower power & CIP boosting isn’t required.
The general limit on gearboxes for overspeeding is 1.5x to 2x to nominal speed.

The generic rule of thumb is:
Metric: (Kw x 9549) = RPM x Torque in Nm
Imperial: (HP x 5252) = RPM x Torque in lb-ft.

The torque value of an electric motor is approximately flat between 30 Hz to 60 Hz. Above 60 Hz, the formulas above apply. Below 30 Hz, the loss in torque is very minimal.
Frame Options
Frame #1 Frameless (w/Four Legs)
Frame #2 Frameless (w/Six Legs)
Frame #3 Heavy Duty Frame
Frame #5 Slider Mount
Frame #4 Service Rail
Our most popular Frame Option!
Design Upgrades
Shaft Blocking Tool
SAVES TIME and increases SAFETY during maintenance, without the need of assistance.
Gapping Port
 Allows for various monitoring sensors as well as EASY ACCESS for gapping procedures.

Vibration Sensor
Installs onto the Gear Housing to closely monitor vibrations (currently in development).
Oil Cooling System
In case very hot product is pumped, the heat can penetrate through the shaft to the needle bearings, and shaft seals. It is recommended to install an oil cooler with oil filter to maintain the oil quality and oil temperature at the needle bearings at max 212° F (100° C).
Seal Water Automation Kit
Allows you to accurately supply seal quench water to the ViscoTwin Mechanical Seals. Includes a Flow Meter with Set Point, a Solenoid or Pneumatic Shut-off Valve, and also Stainless Steel piping as well as compression fittings.
ViscoTec, Inc. Mail: 932 W Mission Ave, Visalia, CA 93277
PROCESSTEC, Inc. • 345 East Tulare Ave, Unit E • Visalia, CA 93277 • Phone: (559) 429-4227 • Fax: (559) 429-4228 • E-mail:
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