HLS Thermal Bolting

Safely Closed Fire Protection Doors – Without Gap

Perfectly functioning fire and smoke protection doors are an indispensable requirement for preventing or limiting damage. Especially in the case of hinged doors, the high heat of a fire might cause the door to distort. This could produce a dangerous gap through which the fire could spread further, in spite of the fire protection door.

The Hot-Locking-Safe thermal bolting offers protection for life and material in a simple and unobtrusive way. The thermal bolting is installed in the frame or the door at those places where there is the highest danger that a gap might occur. Normally the bolt is retracted in the casing and locked there by the soldered strut.  Only when the surrounding temperature rises to about 600 °C and the HLS itself has reached about 65 °C, the soldered strut melts and the spring in the back of the cylinder can push out the bolt. This fixes the door securely to the frame and the door leaf cannot be distorted.

The HLS thermal bolting is available with two different counter plates:

  • HLS Verriegelung EinlauftrichterStandard version (upper picture): the counter plate features just a countersunk bore as intake for the bolting pin.
  • Version for doors which distort more easily (adjoining picture): here the bore in the counter plate is moulded as a funnel to enable the locking pin to easily enter the boring in the counter plate, even when the door has already deformed a little.

IMPORTANT: The HLS thermal bolting may only be installed in accordance with the respective door manufacturer.

Casingzinc-plated steel
Material soldered strutHotmelt
Melting pointat a surrounding temperature of about 600 °C, the soldered strut itself at about 65 °C
Spring forceapprox. 11 N
Stroke23 mm
Application areahinged fire protection doors T30 and T60
Door typestimber and steel doors with timber or steel frames
TestDIN EN 1634-1:2000
Standard model
Model with counterplate with intake guide
All dimensions in mm

Installation-HLS-catchUsually the HLS thermal bolting is installed in the frame. However, it is also possible to fit it into the door leaf. The number and position have to be decided upon together with the door manufacturer.

It is very important that both HLS thermal bolting and its counter plate are mounted exactly opposite each other.

File NameTypeDate of modification
HLS Thermal Boltingpdf2018/07/06
3DPDF Thermal bolting, 710716pdf2018/01/10
DWG Thermal bolting, 710716dwg2018/01/30
DWG Thermal bolting, 710717dwg2018/06/22
STEP Thermal bolting, 710716STEP2018/01/10

Order Information

DescriptionPart No.
Thermal bolting TV2003-50, granulate material, bolt 23 mm stroke, counterplate with intake guide710717
Thermal bolting TV2003-50, granulate material, bolt 23 mm stroke710715