SPOTCHECKSAFETY

2 x 6-axle lines coupled together longitudinally (see Figure 3). As this was close to the strength limitation of the trailer frame, it was jointly agreed to disconnect the two centre axle lines of the trailer, thereby reducing the bending moment in the trailer frame. Basically the reactor was loaded on a 12-axle line trailer, but the axles were grouped into four points, each consisting of five axles (one axle = four tyres = one suspension cylinder) (see Figure 3). By using the momentum formula, one can exactly calculate the load on each group of axles and consequently the load per axle.

Tipping angle

From the sequence of illustrations in Figure 4 (4.1, 4.2, 4.3 and 4.4), we can calculate the theoretical tipping angle of the trailer. The trailer will tip over when the combined CoG of trailer and load passes over the tipping line.

The tipping of a HPT can be avoided by raising the lower side of the trailer and ensure that the trailer bed stays level independent from the road camber (see Figure 4.4). In the example used in Figure 3, we did not take into consideration the

Figure 4.3 Figure 4.4

positive influence of the weight of the trailer, which lowers the CoG of the combined trailer-load combination. We calculated a theoretical tipping angle of 14.4°, based on a four-point suspension system and 9.1° for a three-point suspension system. So why did the trailer tip at a road camber of 2.8°?

The reason for this can be contributed to all of the following factors:  The reactor was not exactly loaded in the centre of the trailer;

 The deflation of tyres at lower side, when the trailer tilts;

 An inaccuracy in the exact location of the CoG of the reactor.

Figure 4.1 Figure 4.2

 And dynamic forces on the day, such as wind, speed and so on. We will continue the investigation of this case in the next issue of HLPFI.

HLPFI

Richard Krabbendam has been a heavy lift specialist during his whole working career after which he formed Krabbendam Advies Service. A Master of Mechanical Engineering from Delft University of Technology, he has worked with BigLift and Mammoet, and was a co-founder of ITREC. He helped to set up Jumbo Offshore and was involved in the development of its super heavy lift carrier fleet, the J-Class, which uses two 900-tonne mast cranes for subsea installation works. Since his retirement from Jumbo he has been working as a freelance trainer/engineering consultant.

www.jumbo-offshore.com www.heavyliftspecialist.com

GOLDHOFER HEAVY-DUTY MODULES

TRANSPORT CHALLENGES. Our heavy-duty modular systems can be individually matched to meet your requirements. At Goldhofer, providing qualifi ed solutions means not only building resilient high quality products, but also giving our customers highly functional solutions for transportation and logistic challenges. Through our comprehensive project engineering and competent after sales program, Goldhofer is there when you really need to get down to business.

Goldhofer products are the result of over 300 years of investment, development of new technologies, and perfection of our customer service. One thing is absolutely clear; Economy is ultimately a function of high resale value, long term durability, and safety. This is what we stand for and promise. Invest in your future. Goldhofer – The Original.

QUALIFIED SOLUTIONS QUALIFIED SOLUTIONS FOR EXTREME

www.heavyliftpfi.com

July/August 2013

61

Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116  |  Page 117  |  Page 118  |  Page 119  |  Page 120  |  Page 121  |  Page 122  |  Page 123  |  Page 124  |  Page 125  |  Page 126  |  Page 127  |  Page 128  |  Page 129  |  Page 130  |  Page 131  |  Page 132  |  Page 133  |  Page 134  |  Page 135  |  Page 136  |  Page 137  |  Page 138  |  Page 139  |  Page 140  |  Page 141  |  Page 142  |  Page 143  |  Page 144