Heidelberg, Komori, and Konica Minolta, along with representatives from domestic printing companies, gathered in Baoding to jointly study the national standard 'Sheet-Fed Lithographic Press'
On November 3, the National Printing Machinery Standardization Technical Committee (SAC/TC 192) held a drafting working group seminar for the national standard 'Sheetfed Offset Press' at Hebei Xinhua First Printing Co., Ltd. This meeting was the last seminar held before the standard review meeting, focusing on consolidating feedback collected during the public consultation phase, with an emphasis on verifying the technical indicators and test data in the draft submitted for review.
More than 20 representatives from the standard drafting units attended the meeting. The participating units covered the full technical spectrum of the sheetfed offset press field both domestically and internationally.
▲ Figure 1: Scene from the drafting working group seminar
The revision focuses on "expanding scope, data interoperability, and measurable indicators"
GB/T 3264 is the fundamental national standard for sheet-fed lithographic printing machines in China. The current version is the 2013 edition of 'Sheet-fed Lithography Printing Machine-Four-sheet and Half-format Format', which has undergone five plate changes in 1982, 1989, 2005, 2010, and 2013.
Compared with the 2013 edition, the changes in this revision mainly reflect six aspects:
(1) Redefine the name and scope of application
The standard name has been changed from "Sheet-fed Lithography Printing Machine Four-sheet and Double-sheet Format" to "Sheet-fed Lithography Printing Press," and its scope of application has been changed from "Four-sheet and Double-Sheet Printing Machines (long side 640 mm to below 1092 mm)" to "Single-sided printing with a maximum feed width of no less than 640 mm." Notably, the 2013 edition included printers with flip-adjustable duplex printing functions in the scope of application, while the revised version clearly states that printers with flip mechanisms are not suitable, making the standard boundaries clearer.
(2) Equipment type and basic parameter expansion
The classification of formats has changed from "high and medium speed by printing speed, monochrome and multicolor by color composition" to "two-color, four-color, and multi-color types by number of printing units; and by maximum paper width input width, divided into four-leaf, half-leaf, and full-sheet types." The 2013 edition previously removed full-sheet content during revisions, but this time the full-sheet type has been re-incorporated. The basic parameter table includes four specification levels: 1150, 1450, 1620, and 1640 mm, with corresponding maximum printing speeds and applicable paper thickness ranges also being increased.
(3) Terminology system updates
New terms such as "maximum paper input width," "impression consistency," "ghosting," and "adapter" have been added. Among them, "impression consistency" assesses the degree of pressure uniformity between different printing units under the same conditions and at the same part of different papers. Together with the original impression uniformity (different parts of the same sheet) and imprint stability (continuous printing on different papers), they form the "three properties of imprinting"; "Adapter" corresponds to new technology forms of data interoperability.
(4) Significant improvement in performance indicators and restructuring of measurement methods
The imprint uniformity limit was raised from "not exceeding 10%" to "not exceeding 3%," and imprint stability was improved from 0.04 to the 3% level; Paper feed accuracy was changed from a single limit of 0.022 mm to graded at 0.025/0.030 mm; Paper transfer accuracy was changed from 0.020 mm to micron-level grading. Ghosting assessment was changed from "ghosting not exceeding 0.020 mm" length to a percentage measurement of "defect characteristic value not exceeding 2%"; The 2013 version of the indicator "dot increase not exceeding 20%" was replaced by new indicator systems such as ink density decay and ink bar dot gradation values, and for the first time included ghosting requirements.
(5) Systematic expansion of chapter structure
The standard has expanded from 8 chapters to 12, adding three new chapters: Key Component Requirements, Installation Requirements, and Data Interoperability. Data interoperability is the first write, requiring printing machines to interact externally via adapters, and specifying data models and open data definitions, providing a unified data interface for single-sheet paper lithography presses connected to smart factories.
(6) Reconstruction of experimental methods and appendix system
Test conditions have been changed from "18°C~28°C, relative humidity 50%~60%" to "(23±5)°C, (55±5)%", clearly using the D50 standard lighting fixture; The printed test chart has been changed from relying on JB/T 5434 test plates to self-produced printed test charts and ink bar test charts in Appendix D according to Appendix C of this standard. The number of appendices has been changed from 3 to 5, including assembly accuracy of major components, data interchangeability, printed test charts, ink bar test charts, and noise measurement point locations.
On-site testing: Standard test charts "printed out, measured"
This seminar supported indicator verification based on measured data. Before the meeting, each drafting unit made plates and samples according to standard printed test drawings and brought samples to the meeting; During the meeting, testing was conducted according to the standards under the specified measurement conditions, with experts directly comparing the actual results item by item, no longer limited to abstract discussions about "determining what is appropriate."
Actual tests also show that the printing test version still needs improvement. Experts checked zone by zone: Zone A is a paper feed accuracy registration area, Area B is a paper transfer accuracy registration area between two adjacent printing units, Zone C is a whole machine paper transfer accuracy registration area, D is a ghosting measurement block, a ground color block and 50% dot area, E is an ink color density attenuation measurement area, F is a ghosting measurement area, and G is a background color area. Suggestions were made for modifications regarding the position, composition, size, arrangement order, and ink color of elements in each zone, and suggestions were made to add auxiliary registration markers and print control strips, forming a new test version layout.
▲ Figure 2 On-site inspection of sample sheets
Next, the National Printing Machinery Standardization Technical Committee will follow the standardization procedures and plans to submit it for review by all committee members at the 2026 National Printing Machinery Standardization Annual Conference on November 17.