1、 Guide for the Optional Class Notation Deep Water Anchoring for Oil Tankers and Bulk Carriers (DWA) GUIDE FOR THE OPTIONAL CLASS NOTATION DEEP WATER ANCHORING FOR OIL TANKERS AND BULK CARRIERS (DWA) MAY 2011 American Bureau of Shipping Incorporated by Act of Legislature of the State of New York 1862
2、 Copyright 2011 American Bureau of Shipping ABS Plaza 16855 Northchase Drive Houston, TX 77060 USA ii ABSGUIDE FOR THE OPTIONAL CLASS NOTATION DEEP WATER ANCHORING FOR OIL TANKERS it is not required as a condition of classification. Means are to be provided for stopping each chain as it is paid out
3、and the windlass should be capable of heaving in either chain. Suitable arrangements are to be provided for securing the anchors and stowing the chains. The typical requirements in the ABS Rules for Building and Classing Steel Vessels (Steel Vessel Rules) cover temporary mooring of a vessel in a har
4、bor or other sheltered water depth up to 64 m. The requirements herein are intended for temporary mooring of a vessel outside a harbor or similar areas of sheltered water with water depth up to 120 m (394 ft) and generally up to conditions 1.54 m/s (3 knots) current, 14 m/s (27 knots) wind (normally
5、 developed at Beaufort 6), and 3 m (10 ft) wave (normally developed at Beaufort 6). 3 Deep Water Equipment Number Anchors and chains are to be in accordance with Section 1, Table 1 and the numbers, mass and sizes of these are to be regulated by the Deep Water Equipment Number (DE) obtained from the
6、following equation: DE = 0.628 ()3.23.2/11628.0+Ewhere = cL3 10-7+ dL2 10-5+ eL 10-3+ f c = 0.0183 (0.0183, 0.000518) d = 0.209 (0.209, 0.0194) e = 0.621 (0.621, 0.189) Section 1 Anchoring, Mooring and Equipment 2 ABSGUIDE FOR THE OPTIONAL CLASS NOTATION DEEP WATER ANCHORING FOR OIL TANKERS anchor a
7、nd chain cable particulars; performance criteria; standard of compliance Windlass arrangement plan showing all of the components of the anchoring/mooring system such as the prime mover, shafting, cable lifter, anchors and chain cables; mooring winches, wires and fairleads, if they form part of the w
8、indlass machinery; brakes; controls; etc. Dimensions, materials, welding details, as applicable, of all torque-transmitting (shafts, gears, clutches, couplings, coupling bolts, etc.) and all load bearing (shaft bearings, cable lifter, sheaves, drums, bed-frames, etc.) components of the windlass and
9、of the winch, where applicable, including brakes, chain stopper (if fitted) and foundation Hydraulic piping system diagram together with system design pressure, relief valve setting, bill of materials, typical pipe joints, as applicable Electric one line diagram together with cable specification and
10、 size; motor controller; protective device rating or setting; as applicable Control, monitoring and instrumentation arrangements Engineering analyses for torque-transmitting and load-bearing components demonstrating their compliance with recognized standards or codes of practice. Analyses for gears
11、are to be in accordance with a recognized standard Windlass foundation structure, including under deck supporting structures and holding down arrangements Plans and data for windlass electric motors including associated gears rated 100 kW (135 hp) and over Calculations demonstrating that the windlas
12、s prime mover is capable of attaining the hoisting speed, the required continuous duty pull and the overload capacity are to be submitted if the “load testing” including “overload” capacity of the entire windlass unit is not carried out at the shop, see 2/7ii) Section 2 Anchor Windlass ABSGUIDE FOR
13、THE OPTIONAL CLASS NOTATION DEEP WATER ANCHORING FOR OIL TANKERS or corresponding to S2-30 min. of IEC 60034-1 Rotating electrical machines Part 1: Rating and performance). The load Zcont, corresponding to the grade 2 and 3 (see Section 1, Table 1) and diameter, d, of the chain cables as follows: Se
14、ction 2 Anchor Windlass 12 ABSGUIDE FOR THE OPTIONAL CLASS NOTATION DEEP WATER ANCHORING FOR OIL TANKERS & BULK CARRIERS (DWA) .2011 ZcontGrade of Chain N kgf lbf 2 50.53d25.15d27310.9d23 55.53d25.66d28034.4d2Unit of d mm mm in. 5.1.3 Overload Capability The windlass prime mover is to be able to pro
15、vide the necessary temporary overload capacity for breaking out the anchor. This temporary overload capacity or “short term pull” is to be at least 1.5 times the continuous duty pull applied for at least 2 minutes. 5.1.4 Hoisting Speed The mean speed of the chain cable during hoisting of the anchor
16、and cable is to be at least 9 m/min (29.5 ft/min). For testing purposes, the speed is to be measured over three shots (82.5 m, 45 fathoms) of chain cable and initially with at least 120 m of chain (65.5 fathoms in length) and the anchor submerged and hanging free. However, the mean speed of the chai
17、n cable hoisting anchor from the depth of 120 m (394 ft) to the depth of 82.5 m (271 ft) is to be at least 4.5 m/min (15 ft/min). 5.1.5 Brake Capacity The capacity of the windlass brake is to be sufficient to stop the anchor and chain cable when paying out the chain cable. Where a chain cable stoppe
18、r is not fitted, the brake is to produce a torque capable of withstanding a pull equal to 80% of the specified minimum breaking strength of the chain cable without any permanent deformation of strength members and without brake slip. Where a chain cable stopper is fitted, 45% of the breaking strengt
19、h may instead be applied. 5.1.6 Chain Cable Stopper Chain cable stopper is to be provided and along with its attachments is to be designed to withstand, without any permanent deformation, 80% of the specified minimum breaking strength of the chain cable. 5.1.7 Support Structure See Subsection 1/13 o
20、f this Guide. 5.3 Hydraulic Systems Hydraulic systems where employed for driving windlasses are to comply with the provisions of 4-6-7/3 of the Steel Vessel Rules. 5.5 Electrical Systems 5.5.1 Electric Motors Electric motors are to meet the requirements of 14-8-3/3 of the Steel Vessel Rules and thos
21、e rated 100 kW and over are to be certified by ABS. Electrical motors installed in the weather are to have enclosures suitable for their location as provided for in 4-8-3/1.11 of the Steel Vessel Rules. Where gears are fitted, they are to meet the requirements of Section 4-3-1 of the Steel Vessel Ru
22、les and those rated 100 kW (135 hp) and over are to be certified by ABS. The Surveyors presence for material tests referred to in 4-3-1/3.1.2 and 4-3-1/3.3 of the Steel Vessel Rules is not required, subject to compliance with 2/3.1. 5.5.2 Electrical Circuits Motor branch circuits are to be protected
23、 in accordance with the provisions of 4-8-2/9.17 of the Steel Vessel Rules and cable sizing is to be in accordance with 4-8-2/7.7.6 of the Steel Vessel Rules. Electrical cables installed in locations subjected to the sea are to be provided with effective mechanical protection as provided for in 4-8-
24、4/21.15 of the Steel Vessel Rules. Section 2 Anchor Windlass ABSGUIDE FOR THE OPTIONAL CLASS NOTATION DEEP WATER ANCHORING FOR OIL TANKERS & BULK CARRIERS (DWA) .2011 13 5.7 Protection of mechanical components To protect mechanical parts of the windlass in the event of excessive loading, an overload
25、 protection such as slip coupling or relief valve is to be fitted to limit the maximum torque, see 2/5.1.3, of the windlass prime mover. 5.9 Coupling Windlasses are to be fitted with couplings which are capable of disengaging between the wildcat (cable lifter) and the drive shaft. Hydraulically or e
26、lectrically operated couplings are to be capable of being disengaged manually. 7 Shop Inspection and Testing Windlasses are to be inspected during fabrication at the manufacturers facilities by a Surveyor for conformance with the approved plans. Acceptance tests, as relevant in the specified standar
27、d of compliance, are to be witnessed by the Surveyor and include the following tests, as a minimum. i) No-load test. The windlass is to be run without load at nominal speed in each direction for a total of 30 minutes. If the windlass is provided with a gear change, additional run in each direction f
28、or 5 minutes at each gear change is required. ii) Load test. The windlass is to be tested to verify that the continuous duty pull, overload capacity and hoisting speed as specified in 2/5.1 can be attained. Where the required “load testing” including “overload” capacity of the entire windlass unit a
29、t the shop is not possible or practical, the manufacturer may submit powering calculations demonstrating that the windlass prime mover is capable of attaining the hoisting speed, the required continuous duty pull and the overload capacity. These calculations are to be validated through testing of an
30、 anchor windlass unit. Once these calculations are validated, they may be used in place of the load tests within the scope of the calculations. Further, in addition to other testing requirements, each prime mover is to be tested at the shop to verify its ability to meet the calculated power requirem
31、ents. Where the prime mover is a hydraulic motor, in addition to the hydraulic motor, the hydraulic pump is also to be tested at the shop. During the testing, the input/output torque, speed, delivery pressures and flow rates of the pump and the hydraulic motor are to be measured, as appropriate. iii
32、) Brake capacity test. The holding power of the brake is to be verified either through testing or by calculation. At the option of the manufacturers, windlass designs and the manufacturing facilities may be approved under the Type Approval Program see Appendix 1-1-A3 of the ABS Rules for Conditions
33、of Classification (Part 1). 9 Onboard Tests Each windlass is to be tested under working conditions after installation onboard to demonstrate satisfactory operation. Each unit is to be independently tested for braking, clutch functioning, lowering and hoisting of chain cable and anchor, proper riding
34、 of the chain over the chain lifter, proper transit of the chain through the hawse pipe and the chain pipe, and effecting proper stowage of the chain and the anchor. It is to be confirmed that anchors properly seat in the stored position and that chain stoppers function as designed if fitted. The me
35、an hoisting speed, as specified in 2/5.1.4, is to be measured and verified. The braking capacity is to be tested by intermittently paying out and holding the chain cable by means of the application of the brake. Where the available water depth is insufficient, the proposed test method will be specia
36、lly considered. 14 ABSGUIDE FOR THE OPTIONAL CLASS NOTATION DEEP WATER ANCHORING FOR OIL TANKERS & BULK CARRIERS (DWA) .2011 Section 3: Surveys After Construction SECTION 3 Surveys after Construction 1 Anchoring System Annual Surveys Anchors and chain cables, anchor windlass including foundation, pr
37、ime mover, shafting, wildcats, brakes, controls, chain stoppers and supporting vessel structure are to be examined, as far as possible. Each windlass is to be operated, as far as possible, for braking, clutch functioning, lowering and hoisting of chain cable and anchor, proper riding of the chain ov
38、er the wildcat, proper transit of the chain through the hawse pipe and chain pipe, and effecting proper stowage of the chain and anchor. 3 Anchoring System Special Periodical Surveys In addition to the requirements of the Anchoring System Annual Survey, the Anchoring System Special Periodical Survey
39、 is to include sufficient examination, tests and checks carried out by the Surveyors to satisfy themselves that the anchoring systems are in or are placed in satisfactory condition and are considered adequate for the new period of class of five (5) years to be assigned, subject to proper maintenance
40、 and operation and to periodic surveys being carried out at the due dates. Anchoring System Special Periodical Survey is to include the following: The anchors and chain cables are to be ranged, examined and the required complement and condition confirmed. The chain locker, holdfasts, hawse pipes and
41、 chain stoppers are to be examined and pumping arrangements of the chain locker operationally tested. At Anchoring System Special Periodical Survey No. 2 and subsequent Anchoring System Special Periodical Surveys, chain cables are to be gauged and renewed in cases where their mean diameter is 12% or
42、 more below the original required nominal size. Where structural alterations to the vessel have resulted in a higher equipment numeral, the original chain cables may be used until their mean diameter has been reduced to 12% below the nominal diameter of the larger cable required by the higher equipment numeral.
