WIRE ROPE SAFETY FENCE
TYPICAL SITE INSTALLATION PROCEDURES
1. All the ropes are supplied on wooden
reels. The two lower ropes are always slightly longer to allow for the inter-weaving between the barrier posts.
The ropes are specially cut to length and wound on to the reel in such a way that when the ropes are run out on
site they should line up exactly with the anchorage positions.
2. The first step in installing
the barrier is to insert a steel post, complete with Z washer dirt excluder, into each of the concrete sockets.
Standard Drawings show where the deflection posts (the ones with the welded lugs on each side) are positioned at
each anchorage.
3. The black plastic pegs must
then be inserted into the posts. It is better to fit the plastic pegs at this stage rather than trying to fit them
before the posts are delivered to site. This is because it is difficult to stack the posts once the pegs are inserted.
4. The two lower ropes must always
be installed first since they interweave between the posts. The lower ropes are the first to come off the reel,
then the upper ropes. The reel should be mounted on a reel stand on the back of a truck or trailer. It is better
if the reel stand does not have bearings. This ensures that the rope remains reasonably taut while it is being
run off.
5. It does not matter which end
of the barrier is used as the start point for running out the ropes. However, all the ropes should be run out from
the same end. This will ensure that the rigging screws are kept away from the area close to the post.
6. Begin running out the first
rope by connecting it into the end anchor as follows. Fit a safety check rope over the end of the rope and then
fit a square polyethylene insert, steel backing plate and two nuts (or the mechanical fitting). Only screw on the
nuts until a full thread has been obtained. Insert the rope into one of the slots in the outermost end anchor,
so that the polyethylene insert is sandwiched between the steel backing plate and the anchor. Please see the Standard
Drawings for the correct assembly of the anchor fittings. (Drawing No. LB/128).
7. Drive slowly alongside the
barrier posts reeling off the rope. Another person walking behind the truck should weave the rope between the posts,
resting it on the plastic pegs. When the end of the rope is reached it will be found that the next rope is tied
to the end with twine. After cutting away the twine the two ropes are connected together using a rigging screw.
At this stage, only engage approx. 25mm thread, leaving the remaining thread for tensioning when all the ropes
have been run out. As mentioned before, provided that the reel stand does not have any bearings, there will be
sufficient friction on the reel stand to keep the rope reasonably taut.
8. When the end anchor is reached,
the rope is connected as follows. Having started running out from the outermost anchor, the ropes now terminate
at the innermost anchor. It will be found that there is approximately two metres of surplus rope, and there is
no threaded fitting swaged on the end. Fit a safety check rope, a square polyethylene insert, steel backing plate
and then attach one of the mechanical anchor fittings over the end of the rope.
A lever hoist should now be used to pull through any slack. It can be attached to the rope by a clamp (available
from LB Wire Ropes), and anchored to the bottom of a Brifen post. The rope is then positioned in one of the slots
in the anchor frame so that the polyethylene insert is sandwiched between the steel backing plate and the anchor.
Ensuring that the mechanical anchor fitting is gripping the rope, the lever hoist can then be removed and the excess
rope can be cut off.
Care must always be taken using a lever hoist to ensure that it is securely connected. If either attachment slips
off while under tension it can result in serious injury to the operator, or person nearby.
9. Take the truck/trailer containing
the reel stand back to the original start point. Running out the second of the lower ropes is largely a repeat
of the above procedures. However, this time, the lower rope starts from the innermost of the pair of end anchors
and finishes at the outermost end anchor.
10. The installation of the upper
ropes is basically a repeat of the procedures used for the lower ropes. The main difference is that the upper ropes
do not interweave between the barrier posts, but are positioned in the slots in the tops of the barrier posts.
11. The first of the upper ropes
should start from the outermost of the pair of end anchors and will terminate at the innermost of the pair of end
anchorages. The second upper rope starts from the innermost end anchor and terminates at the outermost end anchor.
12. The slack in the ropes should
be gradually taken out by tightening up each of the rigging screws in turn. This should be done in stages so that
the slack is taken up evenly along the full length of the barrier, and ensuring that each of the threads engaged
in the rigging screws has at least 50mm of engagement. Also ensure at every anchor that the rope fittings are pressed
down in the anchor slots.
13. Using the tension meter, which
can be quickly attached to the rope, continue to tighten the rigging screws progressively along the full length
of the barrier to increase the tension in the ropes. It is recommended that this be done in stages, building up
to the required tension. The final tension will be determined by the ambient temperature conditions, using the
chart supplied by LB Wire Ropes.
14. The plastic caps and reflectors
can now be fitted to every post.
15. Ensure that all of the safety
check ropes are securely attached to the anchor frames using the clevis fitting which is swaged onto the end of
the safety check rope.
16. When tensioning is completed
the swaged fittings on the ends of every rope and the mechanical anchor fittings should be wrapped in "Denso
tape" or equivalent, or should be given a coating of waterproof grease. This is to ensure that the threads
remain free from corrosion, thus enabling any re-tensioning to be easily performed in future years.
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