CHAIN HOIST FOR MAINTENANCE USE
We were contacted by a Michigan firm to upgrade their old 10 ton cranes in a forge facility. As a part of our service, we discovered their fabrication process needed to lift part of their forge machine higher than any of their existing or new 10 ton hoists could lift. We applied an R&M LoadMate chain hoist for the sole purpose of lifting the forge machine component. The forging company now has a faster and safer means of performing this task, thus allowing less “down time” of the forge machine, resulting in more productivity.
A large Midwest manufacturer contacted Metropolitan Crane to assist in the relocation of a material handling overhead crane systems from facilities in Minnesota and Wisconsin to Pennsylvania and South Dakota.
Initially Metropolitan Crane provided assistance to analyze the value and cost effectiveness of modifying and relocating these crane structures versus purchasing new systems. Since they already owned them and the cranes were current design and in good operating condition it was determined to be a good value and well within budget.
The project began with our review of their existing crane systems and concluded with the installation of the material handling overhead crane systems into both facilities in Pennsylvania and South Dakota.
To do so, the systems were carefully analyzed to determine how best to accomplish this relocation.
The structural steel needed to be modified to fit within the building parameters of each different facility, while obtaining the maximum floor coverage and hook height.
The overhead cranes were fortunately, slightly longer span than was required in this application, thus capable of being shortened.
Also, as part of the relocation one of the cranes required two hoists and an increase in capacity.
Once again fortunately since the crane span was shortened, the allowable load on the crane girder increased enough to allow for the increase in capacity and since the other mechanical requirements such as wheel and axle loads, motor horsepower and torque rating of the gear reducers etc. were adequate enough to Allow the increase., we modified the crane to operate with two hoists.
This process never required travel to the other states prior to the removal and installation of the material handling crane systems.
Facility engineers provided aCad drawings with accurate dimensions indicating the locations where the new crane systems were to be installed.
We had the information for most of the crane systems since we had originally designed, built and installed most of it. The remaining information we didn’t have was field measured and verified.
Once the preliminary process was completed and the design requirements and capabilities of the systems were confirmed, the crane systems were designed and incorporated into the aCad drawings provided by the facility engineers.
When reviewed and approved the following process went into action:
A customer contacted us to solve an issue they had handling heavy materials into the building through an upper level doorway using a monorail hoist. The problem was that there could be no beam extending out of the building; even if this would have been possible, the overhead door operation would not have allowed it.
Our design allowed a hoist to lift loads 8 feet away from the building through the overhead door and bring them into the building under power and allow the overhead door to close.
An additional safety device was installed to protect the overhead door from potential damage.
A customer had an under-running crane system that was rated at 10 ton capacity. They needed a 15 ton capacity crane.
Working with their building architect, we designed a 15 ton under-running double girder bridge crane with a top-running double girder hoist trolley.
Our customer was not only pleased that we could meet their needs, but they’ve been using this same crane setup for over 15 years now.
We were awarded the opportunity to upgrade a very old crane in a fire department service building in a major city. The overhead crane was from an era when cranes were operated from the ground by pulling a rope for each direction of operation. There were six ropes, each having its own handle and each controlling a different movement: up, down, north, south, east and west.
We provided new inverter controls for all motions, added a festoon and traveling pushbutton station and manual and magnetic disconnects. This made the crane safer and easier to operate. Needless to say, the fire department personnel were thrilled with their “new” crane.
A company came to us needing to lift a very large piece of machinery they build. The machining equipment had a weight of up to 60 tons.
Problems: The hook height needed to lift this unit was not possible in their shipping area and the 30 ton crane that existed in the area could not be upgraded cost effectively.
We reviewed what was being lifted and how the lift attached at the lower four corners of the machine, leaving a very top-heavy load.
We provided a freestanding crane system on poured concrete foundations below the existing crane system. This system consisted of two 30 ton capacity cranes, each with two 15 ton capacity hoists. A monitoring system communicated with each hoist. Because four hoists were used to lift, the hitch point was near the four lower corners. This allowed a higher lift because there was no rigging to a single hook. The major issue with a lift of this sort is with a high center of gravity, if one or more hoists stopped or operated at different speeds, the load could be tipped over. The monitoring system controls all four hoists and will not allow operation if it senses any issues. It also sums the total weight of the load while protecting each hoist from an overload. To lift the load, all that was required was to hitch and individually tension all four points, switch to four hoist operation and lift the load. The monitor watches for any issues and will cease to function or correct any issue while lifting and lowering. The system met the customer’s needs.
A company wanted to install an additional crane in their facility. They had two 50 ton capacity cranes with 10 ton auxiliary hoists. They rarely needed the 50 ton hoists and primarily used the 10 ton auxiliary hoist. They also used a third crane with the occasional need of a 15 ton load.
A new 15 ton capacity long span (80’) was an expensive crane. We suggested and sold an 80’ span and 15 ton mono-box crane. This is a single girder crane constructed from steel plate. It is lighter and stronger than a mill beam shape. Also, beams are not economical or logical at this length. A plate box girder was necessary in the double girder design.
The cost savings was mostly in the materials and labor of the second girder that we did not need.
We actually had someone come to us with a need for a small 3 ton crane in a wooden, gravel floored cold storage building. The roof was low, creating a challenge to obtain the desired lift needed to load the materials on the deck of semi trucks.
We provided and installed concrete foundations for a 200’ freestanding top running crane system. We also provided a single girder crane with a low headroom hoist and wireless remote control, much to the satisfaction of our customer.
A Wisconsin customer of ours had been looking for a used 10 ton crane. After considering their needs, we realized that we did not have a used crane available and therefore attempted to find a used crane with the quality and value to meet their needs. While we were looking, the customer did web searches and found a crane, which they purchased from a Texas location.
Prior to the crane’s arrival, we were contacted to quote the installation. That’s when the trouble started. First, we could not understand why it took so long to ship. Once it did ship, it took weeks to arrive. When it finally did arrive, we were able to piece together the story. The crane purchased was shipped in one piece. Built with no construction bolts, it was welded as one entity. The crane was 13 feet wide and needed escorts and special permits from Texas to Wisconsin at a tremendous shipping cost.
The crane was constructed from an antique steel girder from an old crane runway manufactured in the days before welding was invented. It was made from plates and angles riveted together. There was a groove worn in the top of the girder where a rail was once placed. There were bars poorly welded on the lower angles that created the lower flange the hoist was to ride on to hide or reinforce severe corrosion. The hoist provided was a 1940s vintage P&H hoist. Parts have been unavailable for years. The hoist became obsolete in the 1960s. The crane end trucks were from an old double-girder riveted and cast iron construction crane.
When measured before installation, (something we always do), the crane was not square on the correct span. Also, it was too high above the rails to clear the obstructions in the roof. We did not install it. The situation became worse. The company in Texas sent a crew to correct the problems. When they were finished, the “corrections” had made the crane totally unusable. We wouldn’t have wasted the time it took to scrap it.
From this experience, one would think this buyer would have learned a lesson. Sadly, the customer bought another used crane made from old obsolete hoist and crane components. This second crane was too short, so the customer made it longer himself and installed it.
We have no idea what their final total costs were, but we could have supplied new overhead equipment in less time and estimated cost.
Our used cranes always are of an age manufactured and quality so if parts are needed, they are readily available. A hoist or crane that needs parts that are not made or available any longer is scrap, even if it still works fine. Granted, this is the worst case I have ever seen but, once again, BUYER BEWARE!
