SHIM SELECTION / FORCLIP
“We have developed a new test based system using MicroLogix 1400 PLC (Allen Bradley) & Panel View Component 400 HMI (Allen Bradley) hardware & RSLogix 5000 software. System is highly rugged, flexible & cost effective, Increasing productivity of assembly line by 20X & we guarantee measurement accuracy within ± 10 microns”.
Challenge
To develop a test system for accurate measurement of Shim (Gasket) size required to avoid leakage of pressure between Crankcase face & cylinder of compressor. That has been achieved very well by our existing PLC based system.
Solution
Developed a highly rugged, flexible & cost effective, increasing productivity of assembly line by 20X & we guarantee measurement accuracy within ± 10 microns with Allen Bradley world class Automation control system.
What is Shim?
Shims are commonly used to adjust the clearance or space between two parts. For example, shims are inserted into or under bucket tappets to control valve clearances. Clearance is adjusted by changing the thickness of the shim.
What is Gasket?
A gasket is a sealing device made of deformable material usually designed in the form of a ring or sheet. Gaskets create a pressure-tight seam between multiple stationary components, relying on a compression seal to prevent unwanted gas or liquid emissions. These seals are often intended to be resistant to pressure, temperature fluctuations, and in some cases, electrical or electromagnetic forces. Since it uses compression, a gasket is typically more malleable than the components it joins and is able to conform to the shape of the harder surfaces between which it is placed.
System Configuration
The test system, which we created for Shim (Gasket) selection consist of one fixture station for the measurement of distance between piston top & crankcase face position when piston is moving upward with respect to crankcase face. The selected shim width is equal to measured distance to avoid leakage of pressure between crankcase face & cylinder of compressor. The system contains one load sensor for Shim (Gasket) selection. One pneumatic system at fixture station brings the probe of load sensor in contact with crankcase face, piston top applies load at probe of load sensor to measure the width of required Shim (Gasket) size for particular unit. LED lamp glows for indication & pneumatic system opens to pick required Shim (Gasket) size for that particular unit .There are 22 different digital LED lamp indication & pneumatic system for each Shim (Gasket) size as per requirement.
The system uses the MicroLogix 1400(PLC) for controlling the entire process & Panel View Component 400(HMI) to monitor the status of required Shim (Gasket) size for particular unit. Load sensor calibration for precise measurement & accurate Shim (Gasket) selection with respect to master is also available in our system for convenience of user.
System Implementation
We implemented the entire system within 10 man-days. User friendly Allen Bradley software & Hardware helped us to complete system in such short time. An experienced employee takes approximately one minute to measure and select the appropriate shims manually. Error in manual measurements depends on the employee and his fatigue level & it also effect quality policy. But with our new test system, the entire measurement and Shim (Gasket) selection process takes less than three seconds.
The system has two mode of operation:-
- Auto Mode
- Manual Mode
In manual mode, the system carries out all mechanical actions guided by user via HMI. Operator can load Shim (Gasket) manually in all pneumatic arrangements. In auto mode, all operations are carried out automatically after the “cycle start” user acknowledgment. Shim (Gasket) sizes are measured as per load applied by piston top on probe of load sensor. The system guides the user through the message display in the HMI along with LED lamp indication & pneumatic system as per selected Shim (Gasket) size.
Our new test system based on AB hardware’s and software is highly flexible, rugged, and cost-effective, increasing assembly line productivity by 20x and guaranteeing Measurement accuracy within ±10 microns.