INGENIEUR
INGENIEUR
Sample Cross-pattern Tightening Sequence
Adapted from ASME PCC-1 ( 2013 ), Fig . 3
LAWS OF MALAYSIA ACT 514 OCCUPATIONAL SAFETY AND HEALTH ACT 1994 ( OSHA )
Section 15 . General duties of employers and selfemployed persons to their employees . ( 1 ) It shall be the duty of every employer and every selfemployed person to ensure , so far as is practicable , the safety , health and welfare at work of all his employees .
( 2 ) Without prejudice to the generality of subsection ( 1 ), the matters to which the duty extends include in particular- ( c ) the provision of such information , instruction , training , and supervision as is necessary to ensure , so far as is practicable , the safety and health at work of his employees .
General Information for Sharing Only Sample Tightening Method
Sample Joint Connection
Manual Torque Hydraulic Torque Hydraulic Tension Flange Joint
Suitable for relatively low final torque value
Suitable for relatively high final torque value
Utilised cross-pattern tightening sequence with step increment till final torque value
Segregate bolts into sets “ A ” and “ B ” in a staggered manner . Tightening is done alternately via step increment till the final tension value .
Clamp Connectors
Photo of typical “ Clamp Connectors ” and “ Flange Joint ”
Also , the proper maintenance of individual qualifications and experience is important . Furthermore , our national legislation OSHA 1994 Section 15 does specify the general duties of the employer in ensuring the safety , health , and welfare at work of all his employees , including the provision of information , instruction , training , and supervision .
To attain a good flange connection that is leakproof , it is important to perform an initial inspection on the associated components , meaning , the flange surface , gasket , bolt and nut . Personnel needs to be competent in the fundamental skills of gasket placement , joint alignment and , notably , bolt assembly pattern . To achieve evenly distributed compression on the gasket in the flange joint connection , tightening is done via cross pattern with step increments till the final desired value is obtained ( e . g . 30 %, 60 % & 100 %). As a benchmark , an even gap around the flange circumference after tightening indicates evenly distributed stress throughout the flange circumference . Subsequently , the joint may be tagged complete .
54 VOL 94 APRIL-JUNE 2023