Classification code for galvanized rolls

Classification code for galvanized rolls

(1) The classification and code of performance levels are as specified.

Performance classification and code

Level Indicates the application scope of the performance level

General Purpose 01

Mechanical bite 02 zinc layer weight code shall not exceed Z350

The thickness range of punch 03 is ≥0.4mm and the zinc layer weight does not exceed Z275

Deep Draw 04

Special Calming Steel Deep Punch 05

No aging Super deep punch 06

Structure 220, 250, 280, 320, 350, 400, 450, 550 thickness < The 0.4mm plates are not suitable for classes 220, 250, 280 and 320

(2) The type and code of the substrate are specified in Table 2.

Table 2 Types and codes of substrate

Substrate type code

Cold rolled coil

Hot rolled pickling coil H

(3) The type of double-sided equal thickness galvanized layer and the classification and code of coating weight are specified in Table 3. Plates and strips with plating weights not listed in Table 3 are also available upon agreement between the parties.

Table 3 Classification and code of galvanized layer and coating weight

Zinc-iron alloy coating

Coating weight /(g/㎡)(double-sided) code coating weight /(g/㎡)(double-sided) code

(60) (Z60) (40) (ZF40)

80 (Z80) 60 (ZF60)

100 (Z100) 80 (ZF80)

120 (Z120) 100 (ZF100)

150 (Z150) 120 (ZF120)

180 (Z180) 150 (ZF150)

200 (Z200) 180 (ZF180)

220 (Z220)

250 (Z250)

275 (Z2750)

350 (Z350)

450 (Z450)

600 (Z600)

Note: The weight of zinc layer in brackets is subject to negotiation by both parties

3.1 Differential thickness coating can represent different coating weights on the upper and lower surfaces respectively according to half of the coating weight listed in Table 3, such as Z40/90 or ZF30/50. Low zinc layer weight surface appearance may be different from high zinc layer weight surface appearance.

(4) The classification and code of zinc layer surface structure are specified in Table 4.

Due to strain test, after finishing 01~04 grade steel plate and steel strip, users before processing, through an effective straightener to avoid the occurrence of slip line. The polished 05 or 06 grades are non-aging polished plates and strips, which can avoid the formation of slip lines for 6 months.

Table 4 Surface structure of zinc layer and classification and code of polished surface

Surface structure code

It's not just polished

Normal zinc flower N NS

Small zinc flower M MS

Zinc-free flower F FS

Zinc-iron alloy ZF ZFS

(5) The classification and code of surface quality are specified in Table 5.

Table 5 Surface quality classification and code

Surface quality code

Common surface FA

The higher surface FB

Advanced surface FC

(6) The classification and code of surface treatment shall be as specified in Table 6.

Table 6 Classification and code of surface treatment

Surface treatment symbol

Passivation C

Oiling O

Lacquer seal L

Phosphide P

Unprocessed U

6.1 Passivation

The passivation treatment of galvanized layer can reduce the folding rust (white rust) under the condition of tide temperature storage and transportation. But this chemical treatment is limited in its anti-corrosion properties and, moreover, hinders the adhesion of most coatings. This treatment is generally not used in zinc iron alloy coating, in addition to the finish surface, as a routine, the manufacturer of other types of galvanized layer are passivation treatment.

6.2 Oiling

Oil coating can reduce the corrosion of steel plate under wet storage conditions. Reoil of passivated steel plate and steel strip can further reduce the corrosion under wet storage conditions. The oil layer shall be able to be removed with a degreaser that does not damage the zinc layer.

6.3 Lacquer Seal

An additional protection against corrosion, particularly fingerprint resistance, is provided by applying an extremely thin transparent organic coating film. It can improve lubricity during molding and serve as the adhesive base of subsequent coating.

6.4 Phosphating

Through phosphating, the galvanized steel plate of various coating types can be coated without further treatment in addition to normal cleaning. This treatment can improve the adhesion and anticorrosion properties of the coating and reduce the risk of corrosion during storage and transportation. After phosphating and suitable lubricant, can improve the forming property.

6.5 No Processing

Steel plates and strips supplied in accordance with this standard may not be subjected to passivation or surface treatments such as oiling or varnishing or phosphating only if the orderer is responsible for such non-treatment.