This standard specifies the type, basic parameters and dimensions of hand holes with sight glasses for glass-lined equipment, technical requirements, factory documents, packaging, transportation and storage. This standard is applicable to hand holes with sight glasses for glass-lined equipment whose nominal pressure is not greater than PN10 and whose design temperature is higher than -20°C to 200°C.
HG/T 2145.2-2015 Referenced Document
GB 25025 Specification of glass-lined equipment for industry
GB/T 1804 General tolerances Tolerances for linear and angular dimensions without individual tolerance indications