Establishing the Need for an Engineering Standard for Agricultural Hitch Pins

Documented incidents have occurred in which failure or unintentional disengagement of agricultural hitch pins has contributed to property damage and personal injury. An examination of current hitch pin use on a convenient sample of farm operations in Indiana revealed a variety of “non-standard”, worn and damaged and inappropriately sized hitch pins in use. Further interviews with farm operators confirmed that hitch pin misuse, failure or disengagement is a relatively wide spread problem that remains largely unaddressed. On-site observations also suggested a low use of hitch pin safety retaining devices or safety chains. A review of prior research revealed that little attention has been given to the problem and currently no documentation allows for an estimate of the frequency or severity of losses associated with hitch pin misuse, failure or disengagement. No specific engineering standards were found that directly applied to the design, appropriate selection, or loading capacity of agricultural hitch pins. Major suppliers of replacement hitch pins currently provide little or no information on matching hitch pin size to intended applications, and most replacement hitch pins examined were of various foreign origins, with the overwhelming majority imported from China or India. These replacement hitch pins provided no specifications other than diameter, length and in some cases, labeling that indicated that the pins had been “heat treated”.