load transfer factor

TITON Manufacturing Ltd - Head Office 24b Oak Road West Chirton North Ind. Est. North Shields, Tyne & Wear NE29 8SF United Kingdom Tel: + 44 (0) 191 257 6777 Fax: + 44 (0) 191 257 9526 Email: [email protected] Web: www.titonmanufacturing.co.uk Due to continual product improvement all information supplied in this data sheet is subject to change without prior notice E & O E, Due to this phenomena it is essential that an additional load allowance be made when calculating the required operating pressure of the Bolt Tensioner. This additional allowance is known as the Load Transfer Factor. The load transfer factor is determined through calculation as a function of the joint grip length and the nominal diameter of the fastener. Following extensive on-site testing and help from a major oil refinery, a simple to use formulae has been developed to help pre-determine the amount of load lost on transfer Load Transfer Factor Information ! Worked Example Any Bolt Tensioner exhibits a Load Loss as the bolt load is transferred from the Bolt Tensioner to the joints nuts. The bolt load loss is a direct loss of stud elongation; this is due to many different factors, such as Thread Deflections, Radial expansion of the nut and 'Bedding-in' of the nut on the joint. D = Nominal Stud Diameter 1" G = Joint Grip Length 5" W = Required Residual Bolt Load 15 Tonf Load Transfer Factor (L.T.F) = 1.01 + (D/G) = 1.01 + (1/5) = 1.21 Initial Load = Residual Load * L.T.F = 15 * 1.21 = 18.15 Tonf = 40,656 Lbf TITON Tensioner T1 Hydraulic Pressure Area (H.P.A) 3.741" 2 Pump Operating Pressure = Initial Load (Lbf) / H.P.A (in 2 ) = 40,656 / 3.741 = 10867.68 PSI IMPORTANT The above calculation can only be considered as a best estimate for calculating Load Loss for applications with normal site conditions, if however the application's location is not conducive to attaining theoretical, load transfer figures e.g. subsea, we would recommend that a Load Loss Factor of 1.3 be used. Information! D G LTF can be used when calculating pump pressure settings for the Tensioners. On general standard applications such as ANSI & API flanges a 1.3 Technical Data Sheet

Upload: reza

Post on 07-Nov-2015

7 views

Category:

Documents

4 download

Report

Download

Embed Size (px):

DESCRIPTION

load transfer factor cal.

TRANSCRIPT

TITON Manufacturing Ltd - Head Office24b Oak RoadWest Chirton North Ind. Est.North Shields, Tyne & WearNE29 8SFUnited Kingdom

Tel: + 44 (0) 191 257 6777Fax: + 44 (0) 191 257 9526

Email: [email protected]: www.titonmanufacturing.co.ukDue to continual product improvement all information supplied in this data sheet is subject to change without prior notice E & O E,

Due to this phenomena it is essential that an additional load allowance be made when calculating the required operating pressure of the Bolt Tensioner. This additional allowance is known as the Load Transfer Factor.The load transfer factor is determined through calculation as a function of the joint grip length and the nominal diameter of the fastener.Following extensive on-site testing and help from a major oil refinery, a simple to useformulae has been developed to help pre-determine the amount of load lost on transfer

Load Transfer Factor

Information !Worked Example

Any Bolt Tensioner exhibits a Load Loss as the bolt load is transferred from the Bolt Tensioner to the joints nuts.The bolt load loss is a direct loss of stud elongation; this is due to many different factors, such as Thread Deflections, Radial expansion of the nut and 'Bedding-in' of the nut on the joint.

D = Nominal Stud Diameter 1"G = Joint Grip Length 5"W = Required Residual Bolt Load 15 Tonf

Load Transfer Factor (L.T.F) = 1.01 + (D/G)= 1.01 + (1/5)= 1.21

Initial Load = Residual Load * L.T.F= 15 * 1.21= 18.15 Tonf = 40,656 Lbf

TITON Tensioner T1Hydraulic Pressure Area (H.P.A) 3.741"2

Pump Operating Pressure = Initial Load (Lbf) / H.P.A (in2)= 40,656 / 3.741= 10867.68 PSI

IMPORTANTThe above calculation can only be considered as a best estimate for calculating Load Loss for applications with normal site conditions, if however the application's location is not conducive to attaining theoretical, load transfer figures e.g. subsea, we would recommend that a Load Loss Factor of 1.3 be used.

Information!

D

G

LTF can be used when calculating pump pressure settings for the Tensioners.

On general standard applications such as ANSI & API flanges a 1.3

Technical Data Sheet