Why does it need to be made of steel?

 

All too often jobs get started and the field doesn't get the tools they need. If no one says anything to change what's happening, it will just continue. The field staff focus on getting the task done by any means necessary. What does that look like? I was on a job yesterday and caught a bag that demonstrates what happens when no one speaks up. 

This bag is just waiting to fail. Will a board fall out an hit someone? will it fail entirely and catastrophically lose the load. If it doesn't hit anyone in the process, who will change the dynamic? Think about that, and realize that they'll keep doing the same thing until someone says stop, or someone gets hurt. That's how this works. I was on a job running a tower crane once and a guy lifts a sheet of plywood and steps forward to stand the plywood. He disappeared. The plywood was covering a hole. He was OK. Everyone gathered. They all were happy to see him safe. Then they put the plywood back just as it was and went back to work. I stopped swinging the crane. Refused to do anything else until it was addressed. And this is unfortunately how things go in the field. Someone needs to take the lead. 

With crane attachments, anything that supports a load is supposed to be ASME B30.20 rated, which means it's supposed to be made of steel. If you have a rated bag like this show up, it's not for repeated use. The nylon is going to find sharps and fracture just due to constant movements and point loading. Steel doesn't have those fatigue factors. So ASME prescribes steel. Not to mention, I found no rating on this bag which is an issue unto itself. 

If you need structural lifters, www.CraneGear.net has the Eichinger line up from Germany and it's as good as crane and forklift attachments get.  

Don't leave the teams to fend for themselves. You only end up training them that it's OK to live with unsafe practices. In the end, that's as detrimental to the companies they work for as it is to them. And in the end, it's the company managements fault. 

How to plumb a tower crane

 

In the US it's pretty common that we have a surveyor sight up a tower crane mast. OSHA asks for someone Qualified to verify plumb. But what if I told you that most manufacturers don't want this data? They don't prescribe it. They don't control for it. It isn't repeatable. And they consider it junk data. 

It's generally an old idea to shoot up a tower crane for plumb. Liebherr seems to like it for the first tower. The manuals don't indicate if they want it further. I have personally had a surveyor fail to get me the data. The horizontal measurement got Liebherr USA all the data they needed to sign off on the plumb condition of the crane. I do believe that Wolff likes the data point. They also have a 1:1000 requirement whereas everyone else I know of asks for 1:500. There seems to be a different approach at Wolff that I've never dug into. But everyone else that I know of controls the plumb at the base in the horizontal plane. 

The horizontal to the vertical plane is a 90 degree transition. It tells you all you need to know about the vertical. It's possible to have a tower deviation from there, but we are going to be talking about a long standing tower as the current towers and manufacturing techniques have better control. In seven years of my last years in tower cranes I always controlled the horizontal and I've had zero needs to correct the plumb. The only issues have been caused by measuring in winds or due to obviously imperfect towers that can be found. 

What I liked to do was take a digital level from corner to corner on a monoblock anchorage. it's four legs welded together not unlike a 5' tall tower section. Then you use screw jacks or bolts to level off of the concrete infinitely versus trying to get shims under the legs after three measuring rounds with a surveyor. I could set anchorages by myself in 20 minutes usually with a telehandler. And they would be perfect with this technique. 

We need to get the codes changed to match between OSHA, ASME, and the States to accommodate how cranes are manufactured these days. Our practices should be to meet the manufacturer recommendations, and frankly ignore data outside of that. If the government wants to collect the data, great. It's not relevant to how this crane plumb is managed. For risk purposes, you can only follow the manufacturer. I had a crane that the surveyor was reading was out of plumb. The base was perfect. The reading was done the next day and that surveyor thought it was 50% of the threshold, or 1:1000. Weather and surveyor techniques are causing us to put cranes out of plumb to accommodate poor techniques. You don't want the risk of putting a crane out of plumb against the manufacturer recommendations to accommodate a 1960's rule. It's entirely that simple. If your technique on the base is right, the reading of the tower is not your issue. It should be noted this way in your contracts to protect yourself. "Crane Plumb will be controlled by the manufacturer recommended procedure." End of discussion.

Pallet Forks & Safely Using Them

 

Self Leveling forks are the easy way to lift items on a pallet with a crane. You do need a structural lifter with a pallet. OSHA 1926.251 requires a rating. 

Here's the full text:

1926.251(a)(2)

Employers must ensure that rigging equipment:

1926.251(a)(2)(i)

Has permanently affixed and legible identification markings as prescribed by the manufacturer that indicate the recommended safe working load;

1926.251(a)(2)(ii)

Not be loaded in excess of its recommended safe working load as prescribed on the identification markings by the manufacturer; and

1926.251(a)(2)(iii)

Not be used without affixed, legible identification markings, required by paragraph (a)(2)(i) of this section.

1926.251(a)(3)

Rigging equipment, when not in use, shall be removed from the immediate work area so as not to present a hazard to employees.

1926.251(a)(4)

Special custom design grabs, hooks, clamps, or other lifting accessories, for such units as modular panels, prefabricated structures and similar materials, shall be marked to indicate the safe working loads and shall be proof-tested prior to use to 125 percent of their rated load.

They are asking for a structural lifter to be rated. Straps don't provide the ridgidity to resist the torsion applied to the pallet. As a result the pallet could fail in any number of ways to drop everything. This reasoning and rule doesn't change with other items. The plain reading of the rule is clear that "Other Lifting Accessories... Shall be Marked to indicate the Safe working load." 

So we need a structural pallet lifter. Without looking, I'm going to say that I can provide ten options to do this. But even these need to be used properly. 

Most flying forks or crane pallet forks are set up to balance on 40 inch deep pallets. You can specifically order 48" pallet forks. We can manufacture them if they are what you need. But if you don't ask, you'll be getting 40" pallet forks from most manufacturers. What happens is if you put something wider than the forks, it's going to be difficult to balance the forks. The Center of Gravity will be beyond the reach of the center of the attachment point above. The load lean away from the mast and it's not the safest way to lift. 

Notice this center point and that it would struggle to get to the center of the load. Sometimes if this is under 25% of the capacity of the forks, then you can put a foot on the horizontal bar, and grab the top of the mast where it changes direction. Then you can lean back and force the trolley into the best position possible. But you really should have the load within the reach of the forks, and the Center of Gravity inside of the trolley reach, with at least 25% of the rating on the forks to compress the springs. 

You also want that weight as far back as possible. This gap is only exacerbating the problem on a load that is already too long for the physics involved. 

If you need pallet forks, we have them at cranepalletforks.net. Manual, self leveling, or self leveling with a net as an added safety option. This option is what the UK requires. 

Our forks there can be shipped to you. The prices shown cover the delivery to North America. You'll find these are very competitive and the forks are excellent quality. An ASME B30.20 cert comes with every set. If we can help with any other detail, please feel free to reach out at sales@cranegear.net. 

 How we should lift concrete blocks is a common discussion in the field. Rebar rusts and weakens. Cables are meant to be lifted how many times? I've heard stories of failure on cables, but I haven't seen it. I know it to be true with rebar. With rigging you still have to lift it or it gets trapped and it's a pain. The right solution is a ASME B30.20 rated mechanical clamp. A block clamp. 

The Eichinger 1562 Clamp found at www.CraneGear.net can be a good option. The sizes range from 0 to 47" wide on this clamp. Capacities are up to 8800 lbs. And it's fully adjustable as you can see in the video. There is another clamp that could work well too. The 1567 which is not listed on the website is a good choice for this work. If you know what you are going to be lifting, it's easy for us to just get what you need for the job. It'll quickly pay you back when you are working with a $500 and hour crane and crew. If it allows you to work with a forklift instead, it might pay back in as fast as the first day. If you end up wanting to look at other brands, make sure it's as automated as ours is. 

What's also cool is that we might be able to air freight it right to your door for an affordable price. If you want one in 7-10 business days, we'll have you covered so you can get to safe lifting.