Nuts and Bolts

Nuts and Bolts

When you think about it, nuts and bolts will be used for two main purposes. First and foremost, they are used for holding components which need to be properly aligned and second of all, they are used to provide required clamping force. There are also certain instances when they are used for both purposes. After tightening a bolt, it will stretch for a little bit as this stretching helps to impart the required clamping force.

Nuts – endurance levels

However, when using nuts and bolts it is important to check that the bolts are not stretched beyond their endurance levels as this will cause them to yield. If the nuts yield, it would mean that the fastener will not have the ability to provide the desired clamping force. Sometimes, the nuts and bolts can become corroded which will cause damage to the bolt and this in turn will lead to reduction in its total strength as well as its ability to properly stretch itself. When either or both of these conditions, arise it becomes necessary to change the bolts.

Used for valves

Nuts and bolts are also used for valves and are available in a variety of materials that will need to be chosen according to the base material used in the valve. In addition, it is necessary to address the pressure class of the valve as well as the kind of service the valves provide. It is important to pick nuts and bolts that have the proper combination of stretchability and strength. Only the right combination will provide the correct clamping ability.

Cast iron

If you are in need of nuts and bolts to clamp valves that are made out of cast iron, then you will need to factor in the pressure and temperature as well as service needs before picking the correct pair. However, standard grade nuts and bolts can suffice in a majority of instances but you may need to go for ASTM A307 grade A material. Such material has the proper tensile strength and can also provide the right amount of elongation. Such Nuts and bolts will gave the marking (307A) on them and if you are buying companion nuts and bolts then those will have the marking ASTM A563 on them.

One will also need to know how to pick the right kind nuts and bolts for steel as well as alloy valves. Mostly, for such items it is necessary to pick the ASTM A193 bolts and A194 nuts. These are the correct options as they have sufficiently high amount of strength and they also provide the right amount of stretch as well.

If you are looking for nuts and bolts for your valves that are made from carbon steel (plain) then you will need to pick the ones that are of an ASTM A216 grade. Or, you may want to choose bolts that are of A193 B16 grade and the nuts will need to be of A194 grade 4 material.

There are different requirements for Nuts and bolts that are made from stainless steel and there are also different specifications when selecting Nuts and bolts for low temperature needs.

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