Screw 5x20

Self-tapping screw designed for joints in plastic components – steel, zinc-plated, with a countersunk head (Senkkopf) and cross socket. On Kränzle bully 980 TST, 1180 TST and 1000 TST units, it's used in a set of 4 pieces per machine.

Application

The screw secures the side covers (left and right) of the hose reel mounting to the unit frame on the complete bully 980 TST, bully 1180 TST and bully 1000 TST assemblies. The countersunk head allows the screw to sit flush with the cover surface, with no protruding parts at the point where the housing meets the chassis frame. The self-tapping shank cuts into the cover's plastic during installation – no pre-cut thread is needed.

Symptoms – when to replace

• Stripped cross socket in the head – the driver slips, and the screw can't be tightened or removed
• Worn-out thread in the cover's plastic – the screw won't hold, spinning freely with no resistance
• Play in the hose reel mounting side cover – the cover moves, knocks, or vibrates during use/travel
• Corrosion or damaged zinc coating after prolonged outdoor use
• Cracked head or shank from tightening with too much torque

How to choose the right part

• By reference number: 454211 (internal designation 45.421 1)
• By size: 5.0 mm shank diameter, 20 mm length – don't confuse it with the 5.0 x 25 screw (no. 414141) or the 5.0 x 14 screw (no. 43426) from the same mounting set
• By head type: countersunk (Senkkopf), cross socket (Kreuzschlitz)
• By unit model: bully 980 TST / 1180 TST / 1000 TST
• By comparison with the removed screw – if the thread in the cover's plastic is already worn out, check the condition of the hole before reinstalling

[faq]

Is this a metric M5 threaded screw?|No. Despite the "5.0" designation, the Kunststoffschraube 454211 is a self-tapping screw for plastic, not a machine thread per DIN 965 M5. A standard metric M5 screw won't hold in the same hole, because the thread profile is different.

How can I avoid mixing this screw up with others in the same mounting set?|The same area of the bully 980/1180/1000 TST assembly drawing includes three similar screws: 5.0 x 14, 5.0 x 20 (this product) and 5.0 x 25. They differ only in length – it's worth measuring the removed screw with calipers before ordering.

What happens if the thread in the cover's plastic is already worn out?|A new screw alone won't fix a hole in the plastic that's become too wide or oval. In that case, a screw with a slightly larger diameter or a plastic thread insert helps – replacing just the screw won't solve the play problem.

[/faq]