Features/Product Advantages

VdS-certified for use as floor-mounted sprinkler pumps in stationary fire-fighting systems
Efficiency-optimized, laser-welded 2D/3D hydraulic components
Corrosion-resistant impellers, guide vanes, and pump housings
Flow- and degassing-optimized hydraulic components
Reinforced pump housing optimized for flow and NPSH performance
Compact, space-saving, and easy-to-maintain design
Extremely robust coupling guard

Design

High-efficiency, vertical, multistage centrifugal pump with in-line connections; VdS-certified for use as a sprinkler pump in stationary fire-fighting systems.

Equipment/Functions

Pumps in the Helix series feature various standard connection options on the pump housing. The pump housing material must have a minimum elongation at break of 15%.

The Wilo-Helix FIRST pump is VdS-certified for a maximum head of 110 m. Operation must not exceed the specified head or the permissible pressure of 12 bar. The Wilo-Helix FIRST pump housing is made of grey cast iron (EN-GJL-250). VdS requirements mandate the use of JL1040 or an equivalent material.

For Wilo-Helix VF and Wilo-Helix FIRST VF models, the pump shaft, shaft sleeve, impeller, impeller fastening components, and casing wear rings meet VdS requirements for corrosion-resistant metals with a melting point above 800°C.

The pump and motor are connected via a coupling. The drive motor must have sufficient rated power to cover the entire H(Q) performance curve. VdS-certified Helix series pumps must not operate in overload conditions or exceed short-term operating limits. Throughout the acceleration phase from standstill to rated speed, the drive motor torque must exceed the counter-torque exerted by the pump. Motor power and overload ratings are determined at the 5% peak point and an NPSH value of 16 m.

"Q-zul" stands for "Q-zulässig" (permissible flow rate). The operating point must not exceed this limit value. When pumping at 1.2 times the permissible flow rate, the NPSHr must not exceed 5.5 m.

The formula used for the permissible flow rate (Q_permissible) is:

If Q(4.5 m NPSH) × 1.2 does not exceed Q(5.5 m NPSH), then Q_permissible = Q(4.5 m NPSH).

If the result exceeds the value of Q(5.5 m NPSH), then Q_permissible = Q(5.5 m NPSH) / 1.2.

WILO SE must subject the machined or assembled pump housing to a pressure test. Each Helix VF and Helix FIRST VF must be tested in its assembled state:

Test medium: Water
Test pressure: 1.5 times the permissible pressure
No signs of rupture or impermissible plastic deformation during or after the test

Model code

Technical data

Basis for VdS certification:

VdS 2344:2014-07
VdS 2100-07:2013-05

VdS approval number: P 418007

Materials

Wilo-Helix VF pump models (VdS certified) are available in AISI 304 and AISI 316L. Pumps can be supplied with a standard mechanical seal or a cartridge mechanical seal. Wilo-Helix VF and Wilo-Helix FIRST VF meet VdS requirements regarding seal materials such as EPDM and FKM.

Type

Non-self-priming, high-pressure, multistage centrifugal pump featuring a compact, integrated design. The pump shaft and the shaft of the IEC standard motor are connected via a shell coupling. A separate lantern housing with a needle bearing ensures optimal absorption of axial thrust.

Hydraulic components and intermediate bearings on the corrosion-resistant shaft are fitted with stainless steel sleeves to ensure durability. Dedicated lifting lugs facilitate pump installation.

The pump bears a permanent, non-flammable marking.

As-delivered condition

Wilo-Helix VF or Wilo-Helix FIRST VF high-pressure multistage centrifugal pump
Installation and operating instructions
PN 16 version with oval flanges: stainless steel counter-flanges (including corresponding screws, nuts, and gaskets) for Wilo-Helix VF; grey cast iron counter-flanges for Wilo-Helix FIRST VF.