Mounting A Crane Onto A Trailer - What We Need To Know
Mounting cranes onto a trailer is becoming increasingly popular. The flexibility of changing the towing vehicle plus the additional space of a trailer is an attractive proposition for businesses who need a lifting solution.
As ALLMI members, safety is of paramount importance to Penny Hydraulics who adhere to the ALLMI code of practice when designing, manufacturing and installing lifting equipment. There are a number of key considerations that need to be understood when specifying a trailer crane. In this guide, we will help you to understand the questions that Penny Hydraulics will require answers to enable us to specify the correct lifting solution for your trailer.
Q. What are you lifting, how much does it weigh and how far do you need to lift it?
This question helps our Design Engineers to understand the reach and max working load you require to carry out your job. The load and reach effect the stability of the trailer, understanding what is more important, reach or max working load helps us to specify the right crane for the job. Penny Hydraulics can even offer cranes with much greater reach and simply downrate the MWL to ensure the same level of stability is maintained.
Q. How often will you be using the trailer crane?
The frequency of use of the crane (or duty cycle) dictates the appropriate power source. With the correct information, our team can suggest the correct power source for the application. (For example, via the vehicle battery, a slave battery or hydraulically driven by a separate petrol or diesel engine driving a hydraulic powerpack).
Q. What are the dimensions of the trailer?
By understanding the space available on the bed of the trailer means we can advise the best position to install the crane and whether an above floor or below floor option is best.
Q. How many axles does the trailer have?
The number of axles is important as it helps to spread the weight of the load across the trailer and is important when calculating stability.
Q. What is the weight / the payload of the trailer (before conversion)
The weight and payload of the trailer before conversion enables us to calculate the weight of the trailer after the conversion. This, in turn, allows us to calculate the remaining payload of the trailer post-conversion and whether or not this is suitable for the amount you wish to carry.
Q. What is the nose limit of the hitch?
On the A-frame of the trailer is a hitch which has a damper that ensures smooth movement of the trailer under braking. This damper will have a limit – this must be checked against the converted trailer to ensure the limit is not exceeded.
Q. What vehicle(s) will you use to tow the trailer?
Having a trailer with a crane fitted could be a massive benefit to your business. However, to get the full benefit of the conversion you must be able to tow it to where it needs to be used. You must consider:
- The max towing weight of the vehicle (found in the manufacturers' handbook)
- The nose weight limit of the towing vehicle – the limit of the downward force given onto the tow ball (found in the manufacturers' handbook).
Q. Which position do you need the crane to be fitted to the trailer?
As trailers are not as stable as vehicles our design engineers must consider certain factors including
- Nose weight
- Centre of gravity of the trailer
- The number of stabiliser legs required to ensure safe operation of the crane.
Q. Which side(s) of the trailer do you want to be lifting from?
Again, this helps our design engineers to run stability calculations to place support legs that enable us to ensure that the trailer is stable throughout the lift and to specify the slew limits of the crane.
Q. What is the Slew Zone of the Crane?
Penny Hydraulics will calculate where to put slew stops to stop the crane operating in a dangerous area. This adheres to ALLMI’s code of practice and stops the crane operating in areas that could put the operator at risk.
By gaining this information Penny Hydraulics can specify and design the safest and most efficient lifting solution for your trailer and the job you need to carry out.