What is HSFG bolt stands for?
High Strength Friction Grip
HSFG stands for High Strength Friction Grip and as the name suggests they make use of friction. In other words, the friction generated between the plates is equal to the force being put on the plate by the weight of the beam it supports.
What grade are HSFG bolts?
M16 – Self Colour – HSFG – Bolt,Nut & Washers – 8.8 Grade – EN14399. High Strength Friction Grip Bolts (HSFG) bolts are high strength structural bolts that can been tightened to induce tension in the bolt shank.
How do you test a bolt preload?
By inserting a feeler gage in the small gap left by the flattened arches one can measure the distance between the bolt head and washer more precisely. The correct preload is reached when the predetermined gap is achieved between the washer and underhead of the bolt.
Where are HSFG bolts used?
The HSFG bolts are used primarily in construction, Engineering, and structural steelwork. They cater to a variety of industries such as defense, petrochemicals, railways, and mechanical.
Can HSFG bolts be Galvanised?
High strength friction grip bolt, washer & nut. Galvanised. BS EN 14399 part 1, 8.8 Grade.
What is meant by preload in bolt?
Preload is the tension created in a fastener when it is tightened. This tensile force in the bolt creates a compressive force in the bolted joint known as clamp force. For practical purposes, the clamp force in an unloaded bolted joint is assumed to be equal and opposite of the preload.
What are the advantages of HSFG bolts?
The main advantages of HSFG bolted connections are their greater stiffness and their ability to withstand alternating forces. Their behaviour under fatigue loading is also better than that of bearing bolted connections.
What are the advantages of HSFG bolts over bearing bolts?
Explanation: The advantages of HSFG bolts over bearing type bolts are : (i) joints are rigid, (ii) bolts are not subjected to shearing and bearing stresses as load transfer is mainly due to friction, (iii) high static strength due to high frictional resistance, (iv) high strength fatigue since nuts are prevented from …
How much preload should a bolt have?
The preferred bolt preload for structural applications should be at least 75% of the fastener’s proof load for the higher strength fasteners and as high as 90% of the proof load for permanent fasteners. To achieve the benefits of the preloading, the clamping force must be higher than the joint separation load.
What is a preload bolt?
What is bolt preload and why is it important? Preload is the tension created in a fastener when it is tightened. This tensile force in the bolt creates a compressive force in the bolted joint known as clamp force.
What do hsfg and hollobolts stand for?
Most of the time we use standard hexagonal bolts but we also use counter sunk bolts, hollobolts and HSFG bolts. HSFG stands for High Strength Friction Grip and as the name suggests they make use of friction.
What do you need to know about hsfg bolts?
Since the bolts are preloaded the tension in the bolt doesn’t vary as much as in a standard bolt, so they don’t fatigue as quickly. They also will prevent any slip between the plates, which means your fastener won’t come loose. If you find yourself in need of HSFG bolts we will be happy to order them for you.
What does hsfg stand for in a grip?
HSFG stands for High Strength Friction Grip and as the name suggests they make use of friction.
Who is required to install preloaded steel bolts?
For the installation of preloaded bolts, steelwork contractors should employ a certificated bolting coordinator and appropriately trained operatives, in accordance with the requirements of NHSS 20, and the BCSA Standard for Competence in Preloaded Bolting . BS EN 1090-2 gives requirements for four methods of tightening preloaded bolts.