Order number: 6002

The Arch- and Ring-Bending Machine GBR 602 is a manual driven machine. The features of the machine are its solid construction and the small distance of the bending shafts. It comprises two stationary, driven bending shafts and one floating pressure shaft with feed motion. The diameter of the bending shafts is 30 mm. Caused by the small distance of the bending shafts, rings with a small diameter can be bent.

The Arch- and Ring-Bending Machine GBR 602 is provided with an underframe.

The feeding motion is done by means of a threaded spindle. The position of the adjustable pressure shaft is shown on a scale. The bending shafts are manufactured from a special steel, hardened and polished. On both shaft outlets there are guiding rolls, which are adjustable crosswise to the rolling direction, thus enabling a traverse motion of the material. The standard type contains a set of steel rolls for the bending of profiles. The both fixed rolls are split and the floating roll has a material guiding. For rolling of round tubes up to 1" diameter special rolls are available.

Standard Accessories
1 set of standard rolls
1 hand crank
1 spanner SW 36

Weight: about 200 kg

Extra Rolls
No. 6031 - 1 set extra rolls made of steel, hardened, for round tubes 3/4 and ½”
No. 6032 - 1 set extra rolls made of steel, hardened, for round tubes 1" and 3/4"

Normally Arch- and Ring-Bending Machines are equipped with split standard steel rolls, by which most profiles of structural steel, such as flat iron, cross- and edgewise, T-shaped and angular iron, rectangular and square tubes, can be bent to arches and rings. Eventual deviations from the desired radius due to the material characteristics can be corrected by re-rolling or mechanical readjustment.

For the rolling of round tubes out of structural steel special rolls with respective profiles are applied avoiding an oval deformation of the tube cross-section during the rolling process. Also in this case eventual deviations from the desired radius due to the material characteristics can be corrected by re-rolling or mechanical readjustment. The rolling of handrails, underrails and cross bars out of stainless steel and brass for spiral staircases with solid and open newel makes high demands on an accurate execution. For this task the usual Arch- and Ring-Bending Machines have to be equipped with a Pitch Arm. Furthermore special mechanical and electronic measuring devices are available.

1. Pitch Arm
When rolling handrails, underrails and cross-bars for spiral staircases it is necessary to work out a certain pitch of the handrail, besides the arch. For this purpose a Pitch Arm is provided. The Pitch Arm is open on top so that the rolled material can easily be taken out. There is no problem even with a high pitch. Depending on the rolling of handrails for right- or left-turning staircases, the Pitch Arm is mounted either on the left or the right side of the machine. The position of the Pitch Arm is adjusted by a hand wheel and can be read on a digital display or a scale.

2. Plastic Rolls
It is recommendable to use high strength plastic rolls for the rolling of stainless steel- and brass-tubes. In case of steel rolls steel particles might eventually be transferred to the surface of the tubes, which may promote future corrosion. Rolling with plastic rolls avoids nearly any damage of the stainless steel- and brass-tubes.

3. The correction of a spiral arch is practically almost impossible
The correction of a spiral arch is almost impossible, for the reason that rolling of an arch by means of a Pitch Arm deforms the material in the third axis, which makes the spiral arch very hard to handle. The first rolling process is a defined rolling, the second one an undefined rolling. The solution of this problem is accurate rolling by GLASER's auxiliary technical attachments. Due to a Measurement Scheme where the staircase data are defined the desired arch with the respective pitch can perfectly be rolled.

4. Measuring of the bending radius
The radius of the rolled material is indirectly measured resp. calculated by a Radius Sliding Caliper as folIows: First the distance "chord - arch" is measured. Then the radius is read from a radii-table. This is applied to inside and outside radius. In addition to the radii-table GLASER developed a special Radii Calculation Program.

5. Measuring of the pitch in the rolling process
When rolling spirals the tube continuously twists. Before rolling the tube is divided into parts of e.g. 300 mm (control measurement). Then during the rolling process the twisting grade per control measurement is measured in angle degrees at the not yet rolled tube end with a Twisting Measuring Device. From the twisting grade per control measurement results the pitch of the rolled handrail.

6. The radius of a spiral arch
The radius of a spiral arch is larger than the radius of a plain arch due to the pitch. The dimensions, adjustment of the Radius Sliding Caliper as well as the actual radius, are calculated by the Spiral Calculation Program.

7. Spiral Calculation Program
Some years ago GLASER opened a bending centre where handrails, underrails and cross-bars for spiral staircases with open and solid newel as well as various frames are manufactured. The total production program is manufactured according to customer's requirements. Mathematics and technical experience are combined in a Spiral Calculation Program. Experience also induces the input of the different parameters. A Measurement Scheme (on the opposite) shows the floor height, the number of steps, the step width and the step radius. The calculated pitch height is compared with the value measured on site for controlling purposes. The Spiral Calculation Program additionally comprises two further calculation programs for the balustrade construction: a Radius Calculation Program and a Bar-Distance Calculation Program. The Radius Calculation Program has two functions: first it calculates the actual radius from the distance "chord-arch" measured by the Radius Sliding Caliper and on the other hand a desired radius is pre-set and the adjustment of the Radius Sliding Caliper is calculated. The Bar-Distance Calculation-Program determines the number of the necessary balusters calculated from the staircase data: length, angle and max. bar distance (e.g. 120mm width in the clear) and the clear distance between two bars. An even or odd number of balusters is optional.