• Follow us
Home > Knowledge > Content
Sampling inspection of cylindrical helical springs
Feb 22, 2017

 

Sampling inspection of cylindrical helical springs

1. Application range

This standard is applied for cold/hot cylindrically coiled compression springs and extension springs and cold cylindrically coiled twist springs.

2. Reference standard

GB2828 Batch inspection sampling procedures and sampling table (applied for continuous batch inspection)

3. Defeat

Do not meet the requirements of product technical standard, process document and drawing. The defeats can be divided into three degrees:

A  Fatal defeat

B  serious defeat

C  Minor defeat

Table 1

Classification

A defeat

B defeat

C defeat

Cold   coiled compression springs

Decarbonization,   hardness

Spring   characteristics, internal diameter, external diameter, surface defeat,   permanent deformation

Verticality,   total coiling number, free height, uniformity

Cold   coiled extension springs

Spring   characteristics, surface defeat

External   diameter, free length, hook length

Cold   coiled twist springs

Spring   characteristics or free angle, surface defeat

External/internal   diameter, free length, twist torque length

Hot   coiled compression springs

Decarbonization,   hardness

Spring   characteristics, internal diameter, external diameter, surface defeat,   permanent deformation

Verticality,   straightness, total coiling number, free height, uniformity

Hot   coiled extension springs

Decarbonization,   hardness

Spring   characteristics, surface defeat, permanent deformation

External   diameter, free length

 

Note: fatigue life can belong to A defeat