7-Step Spindle Changeover for ID Grinders

Hi guys, Robbie Williams here again. Since a lot of you really liked my last blog “Handy Checklist for Preventive Maintenance” I’ve been thinking: what other “checklists” might be useful for you? Well how about a step-by-step list for users of Okuma ID grinders? Our ID grinders can come with up to 4 different spindles depending on how they’re ordered, and these can be changed out depending on the job you’re doing. One of the problems I’ve seen in the past is that some companies run very large lot sizes and don’t have to do changeovers for a long time. In cases like this operators sometimes don’t remember some of the parameters that need to be changed for the different spindles. For this reason I’ve made a 7-step procedure (with pictures!) to make it easier to perform a spindle changeover on your ID grinder.

7-Step Spindle Changeover for ID Grinders

Step 1: Take these covers off to access the spindle drive belt. (Figure 1)

Step 2: Loosen the jam bolt that holds the motor base plate so that you can adjust the motor base plate to get the belt off. (Figures 2a & 2b)

Step 3: Disconnect/remove lube lines, air line, electrical cable and spindle belt. Remove spindle and install new spindle. (Figure 3)

Step 4: Once you have installed the new spindle, reconnect the lube lines, air line, and electrical cable. Install the spindle drive belt that is associated with the spindle that is being installed and tighten the belt by adjusting the motor base plate. (Figures 4a, 4b & 4c)

Belt size for each spindle
BK65 = 50 X 1080 SE-B-PB 3-340
BK 40 & BK50 = 50 X 1050 SE-B-PB 251201
BK30 & BK25 = 50 X 1026 SE-B-PB 2Y0701u

Step 5: With the new spindle in, you will have to tell the machine which spindle is in the machine by going to the Wheel Spindle Parameter page and setting the Wheel Spindle Select No. to the corresponding number on the plate that is on the side of the spindle. (Figure 5)

BK-65 = 5 16,000 RPM
BK-50 = 6 20,000 RPM
BK-40 = 7 25,000 RPM
BK-30 = 8 32,000 RPM
BK-25 = 9 40,000 RPM

Step 6: After you select the right spindle according to what is in the machine, you will need to set the Wheel Speed Limit, Wheel Spindle Surface Speed, and Wheel Surface Speed limit by going to the Check Data, Wheel Spindle Data screen and entering these codes in the corresponding areas. (Figure 6)

G50G99SW=40000
G98SW=8500
G50G98SW=8500

Step 7: Install any remaining covers and test the spindle.

I hope you find this procedure helpful – feel free to comment below and let me know what you think! And feel free to contact us, or your local Okuma distributor, if you need any help with your ID grinders.

Robbie Williams is Applications Engineer, Okuma America Corporation.