Fork Standards and Inspection

Groups like the American National Standards Institute and the Industrial Truck Standards Development Foundation have mandated specific fork standards and inspection guidelines.
(Courtesy: Oklahoma Dept. of Transportation at flickr.com)

There are a number of fork standards and inspection guidelines that affect the use of fork attachments or extensions when used on forklifts. The Occupational Safety and Health Administration (OSHA), the American National Standards Institute (ANSI), and the Industrial Truck Standards Development Foundation (ITSDF) are some of the groups that mandate standards and inspection guidelines involving forks.

The ANSI/ITSDF B-56.1 Fork Standards deal with the inspection and repair of forks in service on forklift trucks. According to the fork standards:

(a) Forks in use shall be inspected at intervals of not more than 12 months (for single shift operations) or whenever any defect or permanent deformation is detected. Severe applications will require more frequent inspections.
(b) Individual Load Rating of Forks – When forks are used in pairs (the normal arrangement), the rated capacity of each fork shall be at least half of the manufacturer’s rated capacity of the truck, and at the rated load center distance shown on the lift truck nameplate.

ANSI/ITSDF fork standards also set Inspection Guidelines. They include:

Fork inspection should be carried out carefully by trained personnel with the aim of detecting any damage, failure, deformation, etc., which might impair safe use. Any fork that shows such a defect must be withdrawn from service, and shall not be returned to service unless it has been satisfactorily repaired in accordance with paragraph 6.2.8.2.

(a) Surface Cracks
The fork shall be thoroughly examined visually for cracks and if considered necessary, subjected to a non-destructive crack detection process, special attention being paid to the heel and welds attaching the mounting components to the fork blank. This inspection for cracks must also include any special mounting mechanisms of the fork blank to the fork carrier including bolt-type mountings and forged upper mounting arrangements for hook or shaft-type carriages. The forks shall not be returned to service if surface cracks are detected.
(b) Straightness of Blade and Shanks
The straightness of the upper face of the blade and the front face of the shank shall be checked. If the deviation from straightness exceeds 0.5% of the length of the blade and/or the height of the shank, respectively, the fork must not be returned to service until it has been repaired in accordance with paragraph 6.2.8.2.
(c) Fork Angle (upper face of blade to load face of the shank)
Any fork that has a deviation of greater than 3° from the original specification must not be returned to service. The rejected fork shall be reset and tested in accordance with paragraph 6.2.8.2.
(d) Difference in Height of Fork Tips
The difference in height of one set of forks when mounted on the fork carrier shall be checked. If the difference in tip heights exceeds 3% of the length of the blade, the set of forks shall not be returned to service until repaired in accordance with paragraph 6.2.8.2.
(e) Positioning Lock (when originally provided)
It shall be confirmed that the positioning lock is in good repair and correct working order. If any fault is found, the fork shall be withdrawn from service until satisfactory repairs have been effected.
(f) Wear
(1) Fork Blade and Shank – The fork blade and shank shall be thoroughly checked for wear, special attention being paid to the vicinity of the heel. If the thickness is reduced to 90% of its original thickness, the fork shall not be returned to service.
(2) Fork Hooks (where originally provided) – The support face of the top hook and the retaining faces of both hooks shall be checked for wear, crushing and other local deformations. If these are apparent to such an extent that the clearance between the fork and the fork carrier becomes excessive, the fork shall not be returned to service until repaired in accordance with paragraph 6.2.8.2.
(g) Legibility of Marking (when originally provided)
If the fork marking in accordance with paragraph 7.27.2 is not clearly legible, it shall be renewed. Marking shall be renewed per instructions from original supplier.

(Next time: ANSI/ITSDF Repair and Testing Guidelines)