VIROTEC®-telescope pipe length tailor-made

The VIROTEC®-telescope pipe VSI is an adjustable drop nipple for use in fire sprinkler systems. It enables precise adjustment of the sprinkler heads to the position of a suspended ceiling in a vertical direction. The initial length can be adjusted to the position situation by lengthening the pre-fitted double nipple. The length can be adjusted after the system has been installed and in service. Installation time is considerably reduced.

Mounting instruction
  1. Determine the installed length and if necessary lengthen the tele pipe with a 1” double nipple.
  2. If necessary seal the extension and fit the component.
  3. Adjust length; adjustment made by screwing (also possible under pressure).
    Important: The adjusting pipe may only be screwed in up to the start of the outer pipe!

The VIROTEC®-telescope pipe VSI is made up of the following components:
  • Item 1 Outer pipe (CED-coated, black)
  • Item 2 Adjusting pipe (CED-coated, black)
  • Item 3 O-ring (silicon)

All models are ready to install with 1” and ½” inner thread. They have a double nipple for the extension. The length of the double nipple depends on the respective installed position in the suspended ceiling and is freely selectable. The length is adjusted is by screwing the adjusting pipe and outer pipe together. This is also possible under pressure. The seal seals off the gap between the two pipes.


Model Adjustment Connections
Adjustment (inch) Min. length (inch) Max. length (inch) Inlet IT Inlet IT
VS 0.1 2.4 5.1 7.5 1"NPT ½”NPT
VS 0.2 4.0 6.7 10.6 1"NPT ½”NPT
IT= Inner thread


Technical data   Approvals

Surface CED-coated (black)
Weigth Type 0.1: approx. 0.9 p
  Type 0.2: approx. 1.2 p
Thread: Pipe thread 1”NPT, ½”NPT
  according ASME/ANSI B1.20.1
Working temperature 4 °F to +230 °F
Working pressure 360 PSI (PN 25)