DYWI ® Drill Hollow Bar System

Technical Data

Bar Designation
R25N R32N R32S R38N R51L
Nominal Outer Diameter [in] / [mm] 1.00 25 1.26321.2632 1.50 382.00 51
Average Inner Diameter [in] / [mm] 0.59 15 0.9424 0.75190.94 241.5439
Average Cross Section Area[in2] / [mm2] 0.412620.56362 0.724661.006481.17754
Ultimate Load [kips] / [kN] 45 200 63 280 81 360 112500124550
Yield Load [kips] / [kN] 34 150 52 230 63 280 90 400101450
Average Ultimate Tensile Stress [ksi] / [MPa] 111763112773112772112771106729
Average Yield Stress [ksi] / [MPa] 8357292635876008961786596
Nominal Weight [lbs/ft] / [kg/m] 1.412.101.882.802.493.703.435103.975.9
Maximum Drilling Depths [ft] / [m] 39 12 52 16 6620 79248526
Bar Designation
T40N R51N T76N T76S
Nominal Outer Diameter [in] / [mm] 1.57402.00 51 3.00 76 3.00 76
Average Inner Diameter [in] / [mm] 0.71181.30 33 2.09 531.77 45
Average Cross Section Area[in2] / [mm2] 1.328541.611,0363.322,1453.882,504
Ultimate Load [kips] / [kN] 148660180 800 360 1,600 427 1,900
Yield Load [kips] / [kN] 118525142 630 270 1,200 337 1,500
Average Ultimate Tensile Stress [ksi] / [MPa] 112772112772108 745110758
Average Yield Stress [ksi] / [MPa] 89614886088155987599
Nominal Weight [lbs/ft] / [kg/m] 4.506.705.448.111.2916.813.2419.7
Maximum Drilling Depths [ft] / [m] 922898 30 118 36 118 36

NOTE: Maximum allowable, temporary test load is 100% of the yield load. Average cross section area is based on average internal diameter of the bar. The ultimate and yield load capacity are measured values. The ultimate tensile and yield stress are calculated average values. Mill length is 9'-10'' (3m). Longer lengths can be special order. Drilling depths are indicative only and subject to ground conditions and drilling methods. 

DYWI ® Drill Accessories Properties

DYWI ® Drill Hollow Bars for tunnel portal stabilisation
DYWI ® Drill Hollow Bars for tunnel portal stabilisation
DYWI ® Drill Hollow Bars for anchors
DYWI ® Drill Hollow Bars for anchors
Bar DesignationHex Nut Length HCoupler Length BCoupler Outer Diameter ØC
[in][mm][in][mm][in][mm]
R25N 2.44625.911501.4637
R32N 2.56656.301601.6542
R32S 2.56656.301601.6542
R38N 3.15807.091802.0151
R51L 3.54907.872002.4863
T40N2.68686.301602.2457
R51N 3.54907.872002.4863
T76N 3.15808.662203.8297
T76S 3.15808.662203.8297

Coupler and hexnut develop the full load capacity of the bar.
Bearing plates are available in any size and can be made from steel material conforming to ASTM A36 or ASTM A572 grade 50.