Call us on  Reg: Vat no: GB  It's easy to order from us and we're easy to contact All our products are very competitively priced Hints and Tips to make you safer. November 2 posts. October 4 posts. September 5 posts. August 4 posts. July 5 posts. June 4 posts. May 4 posts. April 5 posts. March 5 posts. February 4 posts. January 4 posts. December 3 posts. November 4 posts. October 5 posts. September 4 posts.
August 5 posts. June 3 posts. Add to Bookmarks. Save to My Project. Login or create an account to manage your projects on-site. Already Have an Account? Login Here : Username:. Login Forgot Username or Password. Bookmark added successfully. Need an Account? Create an Account. Please enter the email address associated with your account and we will send you an email containing your username. Email :. Cancel Send Username. Please enter the email address associated with your account and we will send you an email containing your password.
Cancel Send Password. This email address already exists. Please login or retrieve your credentials here. Georgia and S. In fact, of course, nothing could be further from the truth. There are no fewer than 5 different threads for different applications and 10 different standard strength grades defined for each size of bolt.
The situation on is almost as complex with metric nuts which come in a wide variety of types full, thin, nyloc, castellated…..
The difference in strength between different grades is quite dramatic: the highest standard grade being capable of carrying more than three times as much load as the lowest grade. If you are responsible for repairing and maintaining machinery, particularly if that machinery is involved in lifting operation or other safety critical applications then you will be aware of the importance of fitting the right parts in the right way.
This short guide is intended to give you the information you need to be able to correctly identify and use the metric nuts and bolts most commonly found in plant and machinery. Every effort has been made to ensure that the information contained in this document is correct but no guarantee can be given nor liability accepted for errors or omissions. We are always grateful for any comments or criticisms of our technical publications and are happy to offer advice on all aspects of plant and machinery maintenance.
Although various special threads are defined by the ISO standard only two are in common use in most machinery, the others are mainly used in specialist equipment such as precision instruments, optical instruments, etc. The pitch of a thread is the distance between two adjacent threads and is measured in millimetres.
The most common thread diameter and pitch combinations found in plant and machinery are listed in the table below:. Except for the very lowest grades, metric nuts and bolts all carry identification markings which indicate their strength. On the head of each bolt are two numbers separated by a decimal point, the full list includes ten grades from 3. The bolt head should also have a code — normally two or three letters — indicating the manufacturer.
Usually the markings are on the top of the bolt head but sometimes they are on the side. The first number gives the breaking strength of the steel in the bolt. For example, a grade  Similarly a grade 8. A bolt will begin to stretch before it finally breaks, the second number on the head of the bolt indicates how much of the breaking strength the bolt can stand before it starts to stretch.
0コメント