Chapter 6: Fastening Instructions Page 6-1
Chapter 6: Fastening Instructions 6.1 Fastening Control Methods The AFC1200 System is user-programmable to select from three different fastening methods: Torque Control, Angle Control, and Yield Control methods. Each method can be used to perform one-step fastening, or can be configured for up to four (4) steps. 6.1.1 Torque Control Method When using Torque Control, fastening is performed based upon attaining a desired torque value.
Chapter 6: Fastening Instructions w Two-step fastening P After presetting the fastening sequence (Section 7.5 SET SEQUENCE) to perform a two-step fastening, the System fastening parameters (Section 7.1 PARAMETER SET) must be configured according to the engineered fastening specification.
Chapter 6: Fastening Instructions P After presetting the Fastening sequence (Section 7.5 SET SEQUENCE) to perform a three-step fastening, the System fastening parameters (Section 7.1 PARAMETER SET) must be configured according to the Engineered fastening specification.
Chapter 6: Fastening Instructions P After presetting the fastening sequence (Section 7.5 SET SEQUENCE) to perform a four-step fastening, the System fastening parameters (Section 7.1 PARAMETER SET) must be configured according to the Engineered fastening specification.
Chapter 6: Fastening Instructions In Angle Control, fastening is performed based upon attaining a desired torque value and then rotating the fastener a specified number of degrees. Fastening can be performed in from 1 to 4 incremental steps that will successively secure the fastener to a specified torque or angle value before attaining the final number of degrees of rotation.
Chapter 6: Fastening Instructions P After presetting the fastening sequence (Section 7.5 SET SEQUENCE ) to perform a two-step fastening, the System fastening parameters (Section 7.1 PARAMETER SET) must be configured according to the Engineered fastening specification. P Two-step fastening will be used primarily for joints that have a requirement to synchronize with another spindle during the final stage of the rundown (connecting rod, main bearing cap, and any other multiple-spindle unit, for example).
Chapter 6: Fastening Instructions w Three-Step Fastening P After presetting the fastening sequence (Section 7.5 SET SEQUENCE) to perform a three-step fastening, the System fastening parameters (Section 7.1 PARAMETER SET) must be configured according to the Engineered fastening specification.
Chapter 6: Fastening Instructions w Four-Step Fastening P After presetting the fastening sequence (Section 7.5 SET SEQUENCE) to perform a four-step fastening, the System fastening parameters (Section 7.1 PARAMETER SET) must be configured according to the Engineered fastening specification.
Chapter 6: Fastening Instructions 3RD ANGLE 30 ~ 50% of FINAL ANGLE for Hard joints 50 ~ 90% of FINAL ANGLE for Soft joints Set above 2nd ANGLE FINAL ANGLE Engineered fastening specification for rotation angle 1ST STEP (TIME) Maximum allowable fastening cycle time FINAL STEP (TIME) Maximum allowable 2nd, 3rd and Final Step cycle times Page 6-10
Chapter 6: Fastening Instructions 6.1.3 Yield Control Method (U.S.A. PATENT No. 4,894,767) In Yield Control method, fastening is performed based upon attaining a desired permanent elongation or bolt stretch. Fastening can be performed in from 1 to 4 incremental steps that will successively secure the fastener to a specified torque or angle value before attaining the final permanent elongation or bolt stretch.
Chapter 6: Fastening Instructions w Integrated Yield Method Fastening P After presetting the fastening sequence (Section 7.5 SET SEQUENCE) to perform the desired number of steps, the System fastening parameters (Section 7.1 PARAMETER SET) must be configured according to the Engineered fastening specification. P Multiple-step fastening will be performed according to the Torque and Angle Control method procedures.
Chapter 6: Fastening Instructions 6.1.3.2 Area Yield Method The Area Yield Method will be the primary controlling method on fasteners that do not have a clearly definable yield point. These fasteners will exhibit a gradual change in torque rate as the fastener is elongated. This calculation of the elongation area (EA) allows the System to simulate the fastener as if it had displayed a clearly defined yield point.
Chapter 6: Fastening Instructions P For a standard two-step operation the System will fasten to 1ST TORQUE/ANGLE during the specified 1ST STEP time. Once either SPEED CHANGE TORQUE or 1st TORQUE/ANGLE is reached, the System will switch to the specified TORQUE SPEED (SECTION 6.3). When all fasteners have reached 1ST TORQUE/ANGLE, the spindles will synchronize and fasten simultaneously until the desired bolt stretch has been reached, within the specified FINAL STEP time.
Chapter 6: Fastening Instructions 6.2 Monitoring Functions The AFC1200 System is user-programmable to select and set the monitoring limits for torque, angle, time, and three (3) independent torque rate stages. Torque Rate monitoring may be configured to perform two (3) different methods of calculations dependent upon the characteristics of the joint. 6.2.1 Torque Monitoring Torque monitoring is a continuous process whenever the System is operating.
Chapter 6: Fastening Instructions 6.2.3 Point-to-Point Torque Rate Monitoring The AFC1200 System is capable of performing three (3) independent torque rate calculations using two (2) different procedures for calculating the rate value. The first of these procedures is the Point-to-Point method. This method performs the calculation based upon completing a step of the process and then calculating the rate for the full duration of that step.
Chapter 6: Fastening Instructions POINT TO POINT TORQUE RATE TORQUE STD. 3RD RATE HIGH 3 3RD RAT LOW CROSSOVER RATE 2 2ND RATE HIGH 2 1ST RATE HIGH 2ND RATE LOW 1st TORQUE / ANGLE 1 THRESHOLD 1 TORQUE 1ST RATE LOW A FIG. 6-2-3 Point-to-Point Torque Rate Monitoring 6.2.4 Integrated Torque Rate Method The AFC1200 System is capable of performing three (3) independent torque rate calculations using two (2) different procedures for calculating the rate value.
Chapter 6: Fastening Instructions TQ FASTENING TQ CURVE MAGNIFIED INCREMENT ANGLE THRESHOLD 1 TORQUE 1 DEGREE FIG. 6-2-4a Integrated Torque Rate Method Incremental Sampling If no judgment is desired for any or all stages, the high and low limit values should be deleted from the PARAMETER SET screen by first selecting the item, then depressing the DEL key on the keyboard.
Chapter 6: Fastening Instructions TORQUE INTEGRATED TORQUE RATE STD. 3RD RATE HIGH 3 3RD RATE LOW CROSSOVER RATE 2 3 TORQUE RATE 3 2NDRATE HIGH 2 TORQUE RATE 2 2 1 TORQUE RATE 1 1ST RATE HIGH 2ND RATE LOW 1st TORQUE / ANGLE 1 THRESHOLD 1 TORQUE 1ST RATE LOW ANGLE FIG.
Chapter 6: Fastening Instructions 6.3 Speed Functions The AFC1200 System is user-programmable for operations involving multiple speed settings. The use of multiple speeds during the fastening process aids in socket engagement, achieving cycle time and controlling the applied torque during all stages.
Chapter 6: Fastening Instructions w FUNCTION RECOMMENDATION OFFSET CHECK SPEED SEt to the same value as the final torque speed. WHen the oFFSET Check is enabled in the sequence program, this speed will replace the INITIAL SPEed preset INITIAL TIME SET to a duration which will provide sufficient time for socket-tofastener engagement.
Chapter 6: Fastening Instructions 6.4 Reverse Functions The AFC1200 System is capable of reverse operations using three different control methods. There are three independent reverse presetting options to choose from when performing these operations. The following list details the conditions under which each may be used: P Manual switch located on the front of the Main Unit (NO. 1 REVERSE) P PLC REVERSE input signal (NO. 1 REVERSE) P Fastening Sequence program (NO.
Chapter 6: Fastening Instructions 6.5 Torque Recovery The Torque Recovery function is used when the potential for joint relaxation and interaction exists. Under this control method, the fastener(s) are secured to final torque and then held at a programmed value for a programmed period of time. FEC INC. personnel have control of the value and duration of the Torque Recovery function. NOTE: Do not use this method of fastening without the assistance of FEC personnel.
