تبلیغات
Mechanical Men - ??? What is Piston Slap

Create The Future
نویسنده :مهدی کاظمی
تاریخ:یکشنبه 29 بهمن 1391-12:54 ق.ظ

??? What is Piston Slap

Description...

Piston slap is nothing new to piston driven internal combustion engines and compressors. It is the secondary (sideways or perpendicular) movement of a piston against the side of a cylinder bore where the primary movement of a piston is intended to be parallel (up and down) to the cylinder bore. All piston driven internal combustion engines and compressors have a certain amount of piston slap. 


Excessive piston slap occurs when the clearance between the piston and the cylinder bore is too great. The piston to cylinder bore clearance becomes too great either through wear, mismatched pistons and cylinder bores at manufacturing or, a combination of both. The audible noise associated with excessive piston slap is due to the perpendicular impact of the piston against the wall of the cylinder bore. Audible piston slap is typically loudest when the engine is first started up. The pistons then expand with heat reducing the piston to cylinder bore clearance thus, reducing the perpendicular impact of the piston against the cylinder wall and its resulting noise. 

In the case of the famous GM piston slap engine defect, the piston design with hypereutectic (high silicon content aluminum alloy) pistons, reduced or eliminated piston skirts (to reduce reciprocating mass), and a higher ring pack to reduce unburned fuel mixture on the sides of the piston crown have made piston to cylinder bore fit much more critical. The amount of tolerance (variation or margin) in allowable clearance between the piston and cylinder bore to prevent audible piston slap has been reduced by a factor of at least 50%. Consistently hitting the narrower margin for piston to cylinder bore tolerance has not happened for GM during mass production. Thus, some engines have no audible piston slap and some have piston slap on only one or two cylinders. What might have looked really good in testing of hand built engines in the lab hasn't transferred to the production line of this corporate giant. 





How do you treat Achilles tendonitis?
یکشنبه 26 شهریور 1396 04:06 ق.ظ
It's actually a nice and helpful piece of information. I am happy that
you just shared this useful info with us.
Please keep us up to date like this. Thank you for
sharing.
manicure
چهارشنبه 23 فروردین 1396 02:07 ق.ظ
This design is wicked! You certainly know
how to keep a reader amused. Between your wit and your videos, I
was almost moved to start my own blog (well, almost...HaHa!) Great job.

I really enjoyed what you had to say, and more than that,
how you presented it. Too cool!
 
لبخندناراحتچشمک
نیشخندبغلسوال
قلبخجالتزبان
ماچتعجبعصبانی
عینکشیطانگریه
خندهقهقههخداحافظ
سبزقهرهورا
دستگلتفکر