
What are the differences in installation methods between right-angle couplers,swivel couplers,and butt couplers?
Right-angle couplers,swivel couplers,and butt couplers are core components for connecting steel pipes in construction scaffolding.Due to their different functions,their installation methods vary significantly.The specific differences are as follows:
I.Right-angle Couplers(Cross Couplers):For connecting vertically intersecting steel pipes
Connection object:Vertical poles and horizontal bars(intersecting at 90°).
Installation steps:
Align the two"U-shaped"卡口of the right-angle coupler with the intersection of the vertical pole and horizontal bar,ensuring the steel pipes fit tightly against the inner wall of the coupler(gap≤1mm).
Insert an M12 bolt(length≥70mm)and tighten the nut clockwise to a torque of 40-65N·m(over-loosening may cause sliding,while over-tightening may crack the coupler).
Check that the coupler is perpendicular to the steel pipe axis,with an allowable deviation angle≤3°to avoid skewed force.
Key requirements:One right-angle coupler must be used at each intersection;wire substitution is strictly prohibited.Bolts should face uniformly(e.g.,upward or inward)for easy inspection.
II.Swivel Couplers(Universal Couplers):For connecting non-vertically intersecting steel pipes
Connection object:Horizontal bars and diagonal bars(30°-60°angles),diagonal bars and vertical poles,and other non-right-angle intersections.
Installation steps:
Rotate the two adjustable卡口of the swivel coupler according to the intersection angle of the steel pipes,ensuring they fit the outer walls of the two pipes with a contact area≥80%.
After inserting the bolt,pre-tighten to 30N·m,adjust the pipe angle to the designed position,then tighten to 40-65N·m.
Verify the angle with a level or angle gauge to ensure the diagonal support direction meets force requirements(e.g.,brace angles should be 45°-60°).
Key requirements:The distance between swivel couplers on the same diagonal segment must be≥500mm to avoid concentrated stress.They must not be used for right-angle connections(bearing capacity will decrease by over 30%).
III.Butt Couplers(Straight Couplers):For extending steel pipes in the same direction
Connection object:Extending single steel pipes(e.g.,vertical poles or horizontal bars)when their length is insufficient(e.g.,extending a vertical pole to 6m).
Installation steps:
Align the ends of two steel pipes of the same specification(misalignment≤3mm)and insert them into the sleeve of the butt coupler,ensuring the gap between pipe ends≤5mm(to reserve space for thermal expansion and contraction).
Insert two bolts(one on each side)and tighten symmetrically to 40-65N·m(to prevent pipe deviation due to one-sided force).
Check that the coupler sleeve fully covers the pipe joint(exposed length≤10mm)and add horizontal bottom bars or reinforcements at the joint.
Key requirements:Butt couplers should be kept away from stress nodes(e.g.,the distance from a vertical pole joint to the main node≤1/3 of the step distance).The number of butt joints in the same cross-section must be≤50%(to avoid weakening overall rigidity).
The core differences are:Right-angle couplers enforce vertical constraints,swivel couplers adapt to angle changes,and butt couplers enable linear extension.During installation,they must strictly match the connection type and must not be mixed(e.g.,using a butt coupler to connect intersecting pipes will reduce bearing capacity and cause safety accidents).