Bolt Torquing Tension

Scope

This procedure is applicable to all flanged connections in piping systems and connections to equipment regardless of sizes and classes identified and required tightening by bolt torque / tensioning controls at WASIT SKEC Package 3 (Sulfur Recovery Unit SRU), SAUDI ARABIA.

DEFINITIONS

Applied Load The load which we applied by means of a torque wrench. Residual load The load which remains after the torque tightening. Tool Operating Pressure The hydraulic pressure that we applied to a hydraulic torque wrench. Flange tightening Report The report which we submit after the torque tightening. Hydraulic Torque wrench The hydraulic actuated ratchet design torque wrench with square drive and interchangeable castle wrench, which can operate up to maximum working pressure of 10000 psi (690bar).

Objective

The objective of this document is to provide guidelines to ensure all bolted joints are leak Proof and fit for purpose through the following: Correct method Correct material Acceptable joint mating surfaces Proper joint alignment Appropriate new gaskets Acceptability of joint mating surface.

Qualified Technician

Torquing is a specialist skill. The nominated personnel for bolt Torquing & Tensioning will undergo a Hydraulic Torque Wrench Operating course from team Tentec, Manufacturers. Summary qualified personnel together with the limits of their qualifications shall be maintained. Each Person shall carry an ID Badge that indicates the extent of his qualifications.

Safety

Due to the powered nature of tools, with large force generated from high pressure fluid/air and electricity strict safety procedure are following by Calex. For understanding the safety precautions Calex gives training to the operators in Hydraulic Torque Wrench operating course. As also Calex will issue operation instructions and operation manuals to the technicians and Supervisors Personnel shall wear basic PPE as per client’s requirement when working in plant. The minimum requirements are:

1. Safety helmet

2. Safety boot

3. Safety glass

4. One piece coverall

Additional PPE must be provided depending on the nature of the job and hazards associated with it such as respirator, gas detector, chemical suit, airline, dust mask etc. Appendix II tabulates the counter measure for specific risk.

Methods covered:

Bolt Torquing / Tensioning / Tightening flanged joints in which torsional loads are applied to the bolts causing the bolt to stretch, due to the relative movement between the nut threads. Ordinarily, the torque applied should not be outside of the 40-60% of minimum yield range. Tensioning Tightening flanged joints in which an axial force is applied to the bolts causing them to stretch, at which time the nut is snugged and the load is removed. Bolt tensioning is carried out using a hydraulic stud bolt tensioner.

Equipment

Standard Wrenches & Hydraulic operated torque wrench is used for doing the job. All the torque wrenches are operated either by air or electric and the maximum working pressure is 10000Psi /690 Bar. For low clearance job directly fit low profile tools are used. Calex has capability to do the job ranges from hexagonal nut size 27mm to 155 mm.

A REQUIRED TOOLS AND MATERIALS

Standard Wrenches / Ring Spanners Manual Torque wrenches Hydraulic Torque Equipment (combination of air driven hydraulic pump, Sockets, threaded puller and hydraulic hoses Air compressor High pressure air hoses with whiplash arresters Bolts & Nuts / Permanent gaskets/ Marker / Approved Anti-seize lubricants Personnel protection Equipment (PPE) Body protection for working at heights and fall. Consumables

Calibration

The following Torque elements will be calibrated as per standard. Manual Torque wrench with adjustable torque scale Pressure indicator gauge in the hydraulic torque pump Pressure indicator gauge in the hydraulic tensioning pump.