SM 52P Code 13

We have a 2-c perfector that thinks it's dropping the sheet. We have tried everything we can think of, suckers no suckers sheet size slow fast nothing seems to make a diffrence. I have a call in to Heidelberg but still waiting on them to call back. In the mean time the work is stacking up. Any suggestions??

TIA

 

What speed are you trying to run your paper at? You can try back trimming your paper and make sure your blow bar over the storage drum is on and blowing straight down, very important it is straight down.

 

check the suckers that r outside the sheet size u r printing r turned off.
good luck gazman

 

Also important is , that the storage drum is set correctly. All suction holes must be covered completely, and the suckers that are not used must be shut off. There is a light beam and a reflector between the 2 printing units that tend to get soiled and cause these sort of problems. You could try to clean them with a rag.

 

I am thinking that the above SM52 is an older one that does not have the reflector but rather the sniffer piston on the operator side. This style of dropped sheet detector was notorious for detecting dropped sheets. It would be nice to know the serial number of the machine, speed at which the machine detects the dropped sheet and type of paper he is running.

 

We have 2 sm52's at my work, a 4/c and a 6/c. They both have the 2 center sucker feet taped off. (The 2 that are a little farther back then the rest.)

 

If you do that you really have no protection against a dropped sheet.

 

Serial Number

204913 is the serial number it does have the sniffer piston. We can get up to about 7000 iph then we start having problems. We did tape off the center suckers just to try and we still get the code 13 dropped sheet.

Seems like I remember this being a problem when we had the press installed and they added packing behind the transfer jacket and it took care of it.

Were still waiting on Heidelberg, guess since were not broken down, no big deal.

How does that sniffer piston work, can it be adjusted by us or would that be a major mistake??

TIA

JW

 

The sniffer piston can be very tricky and frustrating to set. First thing is get 500 sheets of your best sheet hopefully around 80#, front and back trimmed. Feed sheets at 3000 iph. Once the sheet gets to the storage drum you should see the pin on the left side of the piston box push out, depressing the microswitch. As you increase speed you will see that this pin gets a little movement in it, the faster you go the more movement. The trick is to get the switch adjusted in a position where it will let you run at high speeds but also still detect a "actual" dropped sheet. You will have to experiment with the switch. Final test is take 1 sheet from your 500 and trim 2 more mm off the length of the sheet. Mark this sheet with a huge black X and place it 20 or 30 sheets into your pile. Run your press at your desired speed and the press should detect this "X" sheet as dropped. If this does not happen your switch has been adjusted too close to the piston box. While you should be able to run at a speed of higher than 7000 iph, you may not be able to run at full speed. Bear in mind too that it also could be a vacume leak somewhere in the plumbing of your storage drum. I would make sure your suction pump is sucking properly and the filter in it is good. Make sure the hoses from the pump to the piston are good. Make sure the hosed from the piston to the storage drom are good. It is possible (but unlikely) that the turning valve may be bad too. You should also check the suction cut off time too. This is the time that the tail suckers let go of the sheet. This is very easily adjusted. As you inch the press and look down between the storage drum and side frame you will see a post sticking out of the storage drum. The top of the post closest to you is between 2 pins sticking out of the storage drum. These two pins are welded to a plate which is bolted to the drum. This plate has slotted holes which allow you to slide the plate forward or back, moving the post forward or back, by doing this you can either lenthen or shorted the time the suckers hold the sheet. Best way to check this is mark the current position of the plate so you can move it back to its original position if needed. Than move it all the way forward and feed sheets, move it all the way back and feed sheets, if you notice improvement in either position you will need to adjust suction cut off time and you will need a degree value for this. I might be able to help you with getting a degree value if you need it.