1.  Installation

The pump can be installed horizontally or vertically.

        For the safety reason, it is not allowed to place the driving unit below.


2.   Fixation mode

Foundation design depends on structural dimensions of the pump or pump unit, the connected motor and site installation conditions. Pump with horizontal footing and motor are generally installed the general bottom board.

For detailed dimensions of the pump and pump unit, see the drawing on installation dimensions.


3.   Foundation

3.1   Summary

Foundation can be concrete structure or base with carrying capacity, such as steel structure base.

Reminder: All foundations must bear the weight of pump unit on the whole plane.


3.2  Characteristics of concrete foundation

Foundation must be level; the surface must be flat and clean and can totally bear the load acting on it.

The concrete foundation must be designed in such a manner that the pump bottom board can totally be  kept flat on it and can be secured with proper bolts (refer to drawing of the unit).

 Notice: If the bottom board is partially supported, the middle of the part not being supported will sag or extremely high torque force will be caused on the pump unit. This will influence the calibration of pump unit and cause intenser noise radiation and damages to the pump.


3.3  Calibration of pump unit

The pump unit must be calibrated according to specified height dimensions and system dimensions. Calibration can be conducted by tightening steel filler pieces of each fixing bolts. Total height of the steel filler pieces shall be determined by system dimensions of the equipment. Clearance between steel filler pieces and the bottom board is not allowed.

If the distance between fixing holes is more than 750mm, it is recommended that a steel filler piece is added every 751mm.



Horizontal calibration of pump unit is conducted by using leveling instrument for alignment on the longitudinal and transverse machining surfaces of the pump.

Allowed deviation: Max. 1mm /1m length.


3.4  Fixing of pump unit on the concrete foundation

After calibration of the pump unit on the foundation, tighten fixing bolts crosswise and evenly.

In fabrication of formwork of the concrete foundation, space shall be reserved between top surface of the foundation and bottom surface of the bottom board to calibrate the pump unit and inject mortar.

Concrete foundation after hardening must be flat; the surface shall be flat and clean. Oil stains on the foundation shall be removed. Anchor bolt holes reserved for installation of foundation blots shall be cleaned and purged with air. Prior to installation of the pump unit, concrete foundation surface shall be roughened and clean to ensure well bonding of foundation body and mortar filler.

After calibration is completed on the concrete foundation, mortar filler without contractility shall be used for pouring of bottom board as far as possible. In pouring, insert anchor bolts and pour mortar filler on the whole length of bottom board including anchor bolt holes.

Reminder: When mortar filler is used for pouring or filling, note that the bottom board shall be totally laid on the whole plane and knock on to ensure no cavity.


4.  Check on coupling alignment

When the pump is provided as complete unit with motor, careful assembly and calibration is made in the factory. However, before correct installation and first start of the pump unit, you must check alignment of coupling.

The check can be made with the ruler and feeler, or other suitable instrument (such as laser alignment instrument).

Measurements shall be made on both sides of coupling periphery and it shall be staggered by 90° each time of measurement.

If height deviation, transverse or angular deviation is detected on two coupling halves, two coupling halves shall be aligned through re-alignment of the motor (if necessary, the flat gasket can be used for adjustment).

Clearance between two coupling halves shall be the same on the whole circle.

Spacing between both coupling halves and shaft & ruler shall be the same on the whole circle.


    Fig. 4  Check coupling alignment with feeler and ruler

Reminder: Separately measure axial and radial deviations at the front and circle of two coupling halves. The maximum allowed value shall not exceed 0.1m. After connecting blots are aligned and tightened, the pump

unit shall be easily rotated with hands without any jam-up.

 Notice: Poor coupling alignment can lead to serious wear of the coupling as well as damages to bearings, mechanical sealing and even pump shaft end.


5.  Assembly of pump and driving motor

In case of first assembly of the unit on the installation site, assembly of coupling shall be made according to the following method:

Apply a thin layer of molybdenum disulfide at the end of pump shaft and driving shaft and then install the key.

       Use the jacketing fixture to install the coupling halves on the pump side and motor side respectively until they are aligned with the shaft end. In case of no jacketing fixture, each coupling half can be heated to 100℃(without rubber pad) and it can be easily installed on the shaft end.

   Notice: Avoid collision with any part of the pump and the motor.

Two coupling halves shall be fixed with screws complying with relevant standards.

In assembly of pump and driving motor, note that two coupling halves shall be accurately aligned and a certain distance shall be kept between them. (Refer to our unit drawings and instructions of coupling manufacturer).

For the horizontally-mounted pump unit fixed on the bottom board or foundation, couplings shall be aligned according to requirements in Section 4 of this Chapter.

Install touch protection complying with relevant standards. According of rules on accident protection, the pump can only be operated after unexpected touch protection device is installed.


6.   Spacing required for maintenance and overhaul

     Notice: In order to conduct necessary check, the pump must be able to be reached from any direction.

Enough space shall be left for maintenance and overhaul, especially the space for replacing the pump cartridge. In addition, note that laying or disassembly of the all pipes can not be blocked.


7.  Requirements on pipe connection

7.1  Nominal diameter

  Nominal diameters of suction pipe and discharge pipe shall be the rated values as far as possible; and medium flow velocity in the suction pipe shall not exceed 1m/s to the maximum while maximum medium flow velocity in the discharge pipe does not exceed 3m/s. Avoid the ascent tendency of the suction pipe when laid toward the pump as far as possible.


7.2  Change cross section and direction

          Blind bend and sudden change of cross section and direction shall be avoided.

7.3  Pipe supporting and flange connection

  The pipe shall be connected to the pump with no stress. Supporting must be made close to the pipe; also it shall be easily tightened up to avoid extremely high stress. After blots are loosened, the flange must not deflect and rebound and squeeze. For possible thermal stress on the pipe, proper measures shall be taken; for example, installing a compensator to prevent its influence on the pump.


7.4  Pipe cleaning before installation

Prior to pump installation, all pipe fittings and valves shall be completely washed and cleaned; especially for welded pipes, installation residues such as screws, nuts, welding slag and steel discs can damage parts in the pump.  The user has no right to claim against damages caused by the above residues. Flange gasket seal must not projected inwards. Protective paint and sealing strip must be totally removed from blind flanges, plug gasket and flange surface.

Residual water in the pipe network must be completely discharged.

The pump will be damaged in case of conveying water; three-screw pump is lubricated with the medium for pumping.


7.5  Cut-off valve

          Cut-off valves shall be installed on the inlet and outlet pipes close to the pump.


7.6  Safety valve

  Refer to section 6 in Chapter Ⅳ


7.7  Check valve

   It is recommended that one check valve shall be installed between pump outlet and cut-off valve to prevent opening of cut-off valve at the outlet side at pump stopping which can cause dry running of the pump.


7.8  Vent valve

  The vent valve must be installed at the highest point of the pipe at the outlet side.


7.9  Filtration

  In order to keep the pump free from coarse contaminants, we recommend that the 60~80-mesh filter shall be installed at the suction side of the pump.

  Reminder: Pump service life can be greatly influenced by contamination degree of pumping medium (referring to quantity, dimensions and hardness of abrasive materials).


8.  Safety device and control device

8.1  Pressure gauge and vacuum gauge

  Pressure gauge and vacuum gauge must be separately installed at discharge pipe and suction pipe and auxiliary boosting pipe.


8.2   Safety device on the pressure pipe

  Notice: If safety valve is not installed at the time of delivery of the pump. As long as the pressure pipe has cut-off valve or the possibility of clogging, safety elements must be installed, such as bypass pipe of safety valve, rupture disk, motor protection switch etc. (refer to relevant operating instructions).

 The screw pump is a kind of displacement pump and theoretically it can produce infinite pressure.

When the pressure pipe is closed, in case of clogging or unexpected closing of valve, the pump can produce a pressure that can be tens of times of equipment allowed pressure. It can result in pipe blowout; especially, when the pump is conveying hazardous medium, this must be avoided. Thus, the corresponding safety device shall be installed at the equipment (such as pressure switch).