Gravloks (1 Viewer)

DECROMAX

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Had a toolbox today which resulted in me asking if a pair of Gravloks are load bearing when attached to a vertical rsj. I argued to my supervisor that I don't think they are because they are only relying on the friction applied between the gravlock and the bolt. I have always tended to use them on top of an rsj if it it for load bearing purposes.
 
I have never been comfortable using gravloks side loaded even in pairs , some guys seem to think putting another underneath as a check will help . The fact is if one vibrates the rest will to and come loose .
I always try to find a solid footing either via a standard or spur to take the side load but I have seen plenty of jobs were this has not been done .
 
I've done small, close to the ground cantilevers with Gravvy's on vertical RSJ's, always checked each of them but i was told a few years back by the tag man on Hertel that it wasn't acceptable. But i got away with it because it was in Ireland lol. He was right though, i reckon they ain't load bearing that way.
 
don't think they are load bearing..... but i've checked them with another clamp before now....
 
don't think they are load bearing..... but i've checked them with another clamp before now....
Slip of coupler along section: 10kN
Slip of tube through coupler: 6.5kN
Hanging load vertically: 30kN

They are ok on the vertical as long as used in pairs , but then you boys knew that didn't you ??
 
Slip of coupler along section: 10kN
Slip of tube through coupler: 6.5kN
Hanging load vertically: 30kN

They are ok on the vertical as long as used in pairs , but then you boys knew that didn't you ??
Dont know about the 30kn vertical last time i checked it was 10kn on the x axis ,6.5kn on the y axis. i will see if i can find the drawing and post it
 
Boulton figures

Gravlock® Girder Couplers

Hi All

Below details for Boulton Graveloks.

For fast secure coupling of tube to ‘I’ beam flanges up to 45mm thick whilst comfortably exceeding the BS1139 slip requirements.
NB: must always be used in pairs.

Weight: 1.47kg
Codes:
Sheradised: 007890

Slip of coupler along section: 10kN
Slip of tube through coupler: 6.5kN
Hanging load vertically: 30kN
Maximum safe working loads to BS5973.

All loads are based on PAIRS of Gravlock uniformly and concentrically loaded.


Must admit though I tend not to use them for slip along the section as this will depend on the surface of the section, torque on the bolt, vibrations, etc.

Always prefer to have something else to stop slip along section.

All the best

Chris Eng:)
 
Gravlock® Girder Couplers

Hi All

Below details for Boulton Graveloks.

For fast secure coupling of tube to ‘I’ beam flanges up to 45mm thick whilst comfortably exceeding the BS1139 slip requirements.
NB: must always be used in pairs.

Weight: 1.47kg
Codes:
Sheradised: 007890

Slip of coupler along section: 10kN
Slip of tube through coupler: 6.5kN
Hanging load vertically: 30kN
Maximum safe working loads to BS5973.

All loads are based on PAIRS of Gravlock uniformly and concentrically loaded.


Must admit though I tend not to use them for slip along the section as this will depend on the surface of the section, torque on the bolt, vibrations, etc.

Always prefer to have something else to stop slip along section.

All the best

Chris Eng:)
Nice one Chris
 
well learn something new every day
 
I have often wondered how come we use Gravlocks at all ! It clearly state's on each one that they can only be used in paris !!!:bigsmile:
 
only ever used on steels for handrail in pairs and the odd lay down
 
yeh i know and that was a while ago , hay we only own one bin load that tells u a lot dont it , little giants do the same job , bit like boulton doubles as joiners
 
I have used gravys on quite a few jobs recently, but only for small light duty scaffolds. Pair of gravs will slip on a vertical RSJ at around 1T.
 
usefull to know , didnt know they coulb be used vertically
 
i have never used them on the vertical unless a standard or pickup used to support.if you can knock them off with a butt,then they will slip under load.
take the extra 5 minutes and do it right is my philosophy
 
would rather use them then dh coupler
 
Every day is a school day, I always thought you were not meant to use them on the vertical either.
 
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