Single action concealed door closers with hydraulic check action. Rack and pinion mechanism. Not suitable for use on fire doors. These are a discontinued item and subject to stock availability.

Construction: Briton 527 series are constructed with a cast iron body, steel rack and pinion heat treated and ground, with needle roller bearing.

Performance: Where doors to be closed are near maximum size recommended it is essential they are correctly hung to swing freely, in these instances self oiling (or ball bearing) butt hinges are strongly recommended.

Adjustments: All closers in the series are fitted with two adjustments.
1. To control the speed of closing during the last 80° of cycle.
2. To accelerate closing for the last 10° of cycle to overcome stubborn latch bolts.

Angle of opening: 
The door opening angle can be varied according to fixing position. (Detailed fixing instructions supplied with each closer). Maximum opening angles are given on recommended door sale limits. When maximum angle of opening is required some loss of power may be experienced. We advise the use of next size door closer if doors to be closed are near maximum recommended limits, self oiling (or ball bearing) butt hinges will ensure optimum closer performance.

A door stop should always be used to prevent door opening beyond the limit of the closer or opening back too far and striking the door frame surround. To be effective the door stop should be fitted not less than 2/3rds the door width away from the hinge.

Special design features:

Rack and pinion: A special design feature of the mechanism is that the rack is cut out to take the pinion giving two important advantages.
1. The overall width of the closer body is considerably reduced.
2. The pinion rotates on the centre line of the piston, a geometrically perfect action giving less wear.

Coil strengths: Experts have calculated the coil spring specifications so successfully that we have as yet to hear of a breakage in the field. The springs have been tested to three million cycles.

Maintenance: All internal working parts of the Briton 527 are completely immersed in oil to ensure long working life of closers. Quarterly check that the door closer closes correctly and that all fixing screws are tight. A small quantity of light machine oil applied to the arm knuckle joint and to the door hinges will maintain optimum performance.

Handing