1. Introduction & Core Application
The LWS Series Ram Blowout Preventer (BOP) encompasses single (FZ1821LWS, FZ1835LWS, FZ2821LWS, FZ2835LWS) and double (2FZ1821LWS, 2FZ1835LWS, 2FZ2821LWS, 2FZ2835LWS) ram models, designed as critical well control equipment for oil and gas drilling operations. Tailored for drilling contractors, offshore/onshore oilfield operators, and well maintenance teams, this series is engineered to seal wellbores, control formation fluids, and prevent blowouts—complying with API 16A and GB standards to ensure operational safety in high-pressure drilling environments.
1.1 Product Overview
LWS Ram BOPs are categorized by bore size (179.4mm/7 1/16 in and 279.4mm/11 in) and rated working pressure (21MPa/3000psi and 34.5-35MPa/5000psi), covering diverse drilling scenarios from shallow to medium-deep wells. The series integrates precision hydraulic control, reliable sealing systems, and robust structural design, with dedicated pipe ram assemblies, seal components, and hinge structures to适配 different pipe sizes (1.315” to 9 5/8”) and operational demands.
1.2 Core Functions
Primary functions include wellbore sealing with pipe rams (for specific pipe diameters) and blind rams (for full wellbore closure), hydraulic-driven ram actuation, and mechanical locking to maintain seal integrity under high pressure. The secondary seal system and multi-layer shaft seals enhance leak resistance, while the modular design enables quick component replacement, minimizing downtime during critical operations.
1.3 Structural Features
The LWS Series boasts a forged alloy steel body (Q355B, 42CrMo) for high pressure-bearing capacity and corrosion resistance, with a temperature grade of T-20 to adapt to low-temperature wellsite conditions. Key structural advantages include: ① Modular ram assemblies for flexible pipe size adaptation; ② Dual seal systems (primary piston seals + secondary grease seals) for zero-leakage assurance; ③ Precision hydraulic cylinders with optimized opening/closing capacity (2-5.9L per cylinder) and a closing ratio of 4.5-5.6 for efficient actuation; ④ Reinforced hinge structures and locking screws (18-26 turns per end) for stable structural alignment under vibration and pressure surges.
1.4 Applicable Working Conditions
This series is suitable for onshore and offshore drilling operations, including vertical, directional, and horizontal wells. It operates reliably under: ① Working pressure ranges of 21MPa to 35MPa; ② Ambient temperatures of -20℃ to 60℃; ③ Formation fluid environments (oil, gas, water) with varying salinity and corrosivity; ④ Drilling with casing, tubing, or drill pipes of standard sizes (1.315” to 9 5/8”). It is widely used in oilfields, drilling platforms, and well workover projects requiring strict well control.
1.5 Maintenance & Care Recommendations
Proactive maintenance is critical to extending the LWS Ram BOP’s service life and ensuring operational safety. Key recommendations include: ① Conduct hydrostatic testing annually (per API 16A) to verify pressure-bearing capacity—test pressure is 1.25 times the rated working pressure; ② Replace seal components (O-rings, wiper rings, lip rings) every 6-12 months or after 500 actuation cycles, using only genuine parts to maintain compatibility; ③ Lubricate hinge pins, locking screws, and hydraulic cylinders monthly with anti-corrosion, high-pressure grease (GB1152 M10×1 standard); ④ Inspect ram blocks and rubber seals for wear, cracks, or deformation before each use—replace if wear depth exceeds 0.5mm; ⑤ Store spare parts in a dry, dust-free environment with temperature control to avoid seal hardening or metal corrosion; ⑥ Retorque cylinder bolts and socket cap screws after the first 100 operating hours to account for initial settling.
LWS Ram BOP
Specification and main technical parameters of Ram BOP
Model | Single Ram BOP | Double Ram BOP | Single Ram BOP | Double Ram BOP |
Bore | FZ1821LWS | 2FZ1821LWS | FZ1835LWS | 2FZ1835LWS |
Rated working pressure | 179.4mm（7 1/16 in） | 179.4mm（7 1/16 in） | ||
Hydrostatic test pressure | 21MPa（3000psi） | 35Mpa（5000psi） | ||
Hydraulic control rated working pressure | 42MPa (6000psi) | 52.5MPa（7500psi） | ||
Recommended hydraulic control operation pressure | 21 MPa（3000psi） | |||
Model | 8.4-10 .5MPa(1200-1500psi) | |||
Opening capacity of hydraulic cylinder | 2 L×2 | 2 L×4 | 2 L×2 | 2 L×4 |
Closing capacity of hydraulic cylinder | 2.4 L×2 | 2.4 L×4 | 2.4 L×2 | 2.4 L×4 |
Temperature grade of metal material | T-20 | |||
Closing Ratio | 4.6 | 4.6 | ||
Locking Screw turns (each end) | 18 | 18 | ||
Weight | 1072kg | 1945kg | 1114kg | 2007kg |
Model | Single Ram BOP | Double Ram BOP | Single Ram BOP | Double Ram BOP |
Bore | FZ2821LWS | 2FZ2821LWS | FZ2835LWS | 2FZ2835LWS |
Rated working pressure | 279.4mm（11 in） | 279.4mm（11 in） | ||
Hydrostatic test pressure | 21MPa（3000psi） | 34.5Mpa（5000psi） | ||
Hydraulic control rated working pressure | 42MPa (6000psi) | 51.7MPa（7500psi） | ||
Recommended hydraulic control operation pressure | 21 MPa（3000psi） | |||
Model | 8.4-10 .5MPa(1200-1500psi) | |||
Opening capacity of hydraulic cylinder | 2.7L×2 | 2.7L×4 | 5.2 L×2 | 5.2 L×4 |
Closing capacity of hydraulic cylinder | 3.3L×2 | 3.3L×4 | 5.9 L×2 | 5.9 L×4 |
Temperature grade of metal material | T-20 | |||
Closing Ratio | 4.5 | 5.6 | ||
Locking Screw turns (each end) | 23.5 | 26 | ||
Weight | 1456kg | 2806kg | 2889kg | 5281kg |
Parts of pipe ram of 2FZ1821LWS /2FZ1835LWS BOP
Pipe size | Pipe ram assembly Name(Qty) | |||||
Ram assembly（2） | Ram block（2） | Retaining Screw （4） | Holder（2） | Retracting Screw （4） | Rubber（2） | |
1.315” | 2FZ1835DLWS.02A-00 | 2FZ1835DLWS.02A-03 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02A-04-00 |
1.660” | 2FZ1835DLWS.02B-00 | 2FZ1835DLWS.02B-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02B-02-00 |
1.990″ | 2FZ1835DLWS.02C-00 | 2FZ1835DLWS.02C-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02C-02-00 |
2 1/16” | 2FZ1835DLWS.02D-00 | 2FZ1835DLWS.02D-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02D-02-00 |
2 3/8” | 2FZ1835DLWS.02E-00 | 2FZ1835DLWS.02E-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02E-02-00 |
2 7/8” | 2FZ1835DLWS.02F-00 | 2FZ1835DLWS.02F-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02F-02-00 |
3 1/2” | 2FZ1835DLWS.02G-00 | 2FZ1835DLWS.02G-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02G-02-00 |
4” | 2FZ1835DLWS.02H-00 | 2FZ1835DLWS.02H-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02H-02-00 |
4 1/2” | 2FZ1835DLWS.02I-00 | 2FZ1835DLWS.02I-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02I-02-00 |
4 3/4” | 2FZ1835DLWS.02J-00 | 2FZ1835DLWS.02J-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02J-02-00 |
5” | 2FZ1835DLWS.02K-00 | 2FZ1835DLWS.02K-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02K-02-00 |
5 1/2” | 2FZ1835DLWS.02L-00 | 2FZ1835DLWS.02L-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02L-02-00 |
Blind | 2FZ1835DLWS.02M-00 | 2FZ1835DLWS.02M-01 | ANSI B18.3-1982 1/2-13UNC-2B×1.5 | 2FZ1835DLWS.02A-01 | 2FZ1835DLWS.02A-02 | 2FZ1835DLWS.02M-02-00 |
Parts of pipe ram of 2FZ2821LWS BOP
Pipe size | Pipe ram assembly Name(Qty) | |||||
Ram assembly（2） | Ram block（2） | Retaining Screw （4） | Holder（2） | Retracting Screw （4） | Rubber（2） | |
Fully enclosed | 2FZ2821DLWS.02A-00 | 2FZ2821DLWS.02A-03 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02A.01-00 |
1.315” | 2FZ2821DLWS.02B-00 | 2FZ2821DLWS.02B-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02B.01-00 |
1.660” | 2FZ2821DLWS.02C-00 | 2FZ2821DLWS.02C-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02C.01-00 |
1.90″ | 2FZ2821DLWS.02D-00 | 2FZ2821DLWS.02D-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02D.01-00 |
2 1/16” | 2FZ2821DLWS.02E-00 | 2FZ2821DLWS.02E-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02E-01-00 |
2 3/8” | 2FZ2821DLWS.02F-00 | 2FZ2821DLWS.02F-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02F.01-00 |
2 7/8” | 2FZ2821DLWS.02G-00 | 2FZ2821DLWS.02G-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02G.01-00 |
3 1/2” | 2FZ2821DLWS.02H-00 | 2FZ2821DLWS.02H-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02H.01-00 |
4” | 2FZ2821DLWS.02I-00 | 2FZ2821DLWS.02I-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02I.01-00 |
4 1/4” | 2FZ2821DLWS.02J-00 | 2FZ2821DLWS.02J-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02J.01-00 |
4 1/2” | 2FZ2821DLWS.02K-00 | 2FZ2821DLWS.02K-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02K.01-00 |
4 5/8” | 2FZ2821DLWS.02L-00 | 2FZ2821DLWS.02L-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02L.01-00 |
5” | 2FZ2821DLWS.02M-00 | 2FZ2821DLWS.02M-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02M.01-00 |
5 1/2” | 2FZ2821DLWS.02N-00 | 2FZ2821DLWS.02N-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02N.01-00 |
6 1/4” | 2FZ2821DLWS.02O-00 | 2FZ2821DLWS.02O-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02O.01-00 |
6 5/8” | 2FZ2821DLWS.02P-00 | 2FZ2821DLWS.02P-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02P.01-00 |
7” | 2FZ2821DLWS.02Q-00 | 2FZ2821DLWS.02Q-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02Q.01-00 |
7 5/8” | 2FZ2821DLWS.02R-00 | 2FZ2821DLWS.02R-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02R.01-00 |
8 5/8” | 2FZ2821DLWS.02S-00 | 2FZ2821DLWS.02S-02 | 2FZ2835ALWS.02A-05 | 2FZ2821DLWS.02A-02 | 2FZ2835ALWS.02A-03 | 2FZ2821DLWS.02S.01-00 |
Parts of pipe ram of 2FZ2835LWS BOP
Table 3-3 Parts of pipe ram of 2FZ2835LWS BOP Pipe size | Pipe ram assembly Name(Qty) | |||||
Ram assembly（2） | Ram block（2） | Retaining Screw （4） | Holder（2） | Retracting Screw （4） | Rubber（2） | |
2 7/8” | 2FZ2835ALWS.02A-00 | 2FZ2835ALWS.02A-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02A.04-00 |
3 1/2” | 2FZ2835ALWS.02B-00 | 2FZ2835ALWS.02B-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02B.04-00 |
4 1/2” | 2FZ2835ALWS.02C-00 | 2FZ2835ALWS.02C-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02C.04-00 |
5” | 2FZ2835ALWS.02D-00 | 2FZ2835ALWS.02D-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02D.04-00 |
7” | 2FZ2835ALWS.02E-00 | 2FZ2835ALWS.02E-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02E-04-00 |
Fully enclosed | 2FZ2835ALWS.02F-00 | 2FZ2835ALWS.02F-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02F.04-00 |
1.315” | 2FZ2835ALWS.02G-00 | 2FZ2835ALWS.02G-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02G.04-00 |
1.660” | 2FZ2835ALWS.02H-00 | 2FZ2835ALWS.02H-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02H.04-00 |
1.900” | 2FZ2835ALWS.02I-00 | 2FZ2835ALWS.02I-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02I.04-00 |
2 1/16” | 2FZ2835ALWS.02J-00 | 2FZ2835ALWS.02J-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02J.04-00 |
2 3/8” | 2FZ2835ALWS.02K-00 | 2FZ2835ALWS.02K-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02K.04-00 |
4” | 2FZ2835ALWS.02L-00 | 2FZ2835ALWS.02L-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02L.04-00 |
4 3/8” | 2FZ2835ALWS.02M-00 | 2FZ2835ALWS.02M-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02M.04-00 |
5 1/2” | 2FZ2835ALWS.02N-00 | 2FZ2835ALWS.02N-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02N.04-00 |
6 5/8” | 2FZ2835ALWS.02O-00 | 2FZ2835ALWS.02O-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02O.04-00 |
7 5/8” | 2FZ2835ALWS.02P-00 | 2FZ2835ALWS.02P-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02P.04-00 |
8 5/8” | 2FZ2835ALWS.02Q-00 | 2FZ2835ALWS.02Q-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02Q.04-00 |
6 1/4” | 2FZ2835ALWS.02R-00 | 2FZ2835ALWS.02R-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02R.04-00 |
9 5/8” | 2FZ2835ALWS.02S-00 | 2FZ2835ALWS.02S-02 | 2FZ2835ALWS.02A-05 | 2FZ2835ALWS.02A-01 | 2FZ2835ALWS.02A-03 | 2FZ2835ALWS.02S.04-00 |
Part list of Ram Shaft Seal Assembly of 2FZ1821LWS/2FZ1835LWS/2FZ2821LWS
Description | 2FZ1821LWS P/N 2FZ1835LWS P/N | 2FZ2821LWS P/N |
Wiper ring | 2FZ1835DLWS.03.02-01 | 2FZ2821DLWS.03.02-03 |
Support ring | 2FZ1835DLWS.03.02-02 | 2FZ2821DLWS.03.02-02 |
O-ring | 90×5.3 | 92.5×5.3 |
O-ring | 75×5.3 | 75×5.3 |
Retainer ring | 2FZ1835DLWS.03-17 | 2FZ2821DLWS.03.02-01 |
Part list of Ram Shaft Seal Assembly of 2FZ2835LWS
Description | P/N |
Retainer ring | 2FZ2835ALWS.03.02-01 |
Wiper ring | 2FZ2835ALWS.03.02-03 |
Holder ,Wiper ring | 2FZ2835ALWS.03.02-02 |
Lipring | 2FZ2835ALWS.03.02.04-00 |
Seal Back-up Ring | 2FZ2835ALWS.03.02-05 |
Lipring (cover) | 2FZ2835ALWS.03.02-06 |
Parts list of Secondary Seal System of 2FZ2835LWS
Description | P/N |
Z1″ External hexagonal blocking | SFZ2835-38 |
Cock | 2FZ2835ALWS.03-03 |
Secondary sealing grease | 2 |
Z1/2″ Internal hexagonal plug screw with hole | SFZ2835-40 |
2FZ1821LWS/2FZ1835LWS/2FZ2821LWS Parts list of Locking Shaft Seal Assembly
Description | 2FZ1821LWS P/N 2FZ1835LWS P/N | 2FZ2821LWS P/N |
Retainer Ring | 2FZ1835DLWS.03-13 | 2FZ2821DLWS.03.13-01 |
O-ring | 36.5×5.3 | 2FZ2821DLWS.03.13-04 |
O-ring | 71×3.55 | 73×3.55 |
Support ring | 2FZ1835DLWS.03.09-02 | 2FZ2821DLWS.03.13-02 |
Wiper ring | 2FZ1835DLWS.03.09-01 | 2FZ2821DLWS.03.13-03 |
2FZ2835LWS Parts list of Locking Shaft Seal Assembly
Description | P/N |
Retainer Ring | 2FZ2835ALWS.03.14-01 |
Thrust Shaft Sleeve | 2FZ2835ALWS.03.14-02 |
Lip ring | 2FZ2835ALWS.03.14-03-00 |
Wiper Seat Retainer | 2FZ2835ALWS.03.14-04 |
Wiper Ring | 2FZ2835ALWS.03.14-05 |
Parts list of Hinge structure
Description | FZ1821LWS Part No./Model | FZ1835LWS Part No./Model |
Plug NPT1/2 | JB/ZQ4447-1997 | JB/ZQ4447-1997 |
Hinge Pin | - | 2FZ1835DLWS-07 |
13a (Left) | Left Hinge Bracket | 2FZ1835DLWS-05 |
13a (Right) | Right Hinge Bracket | 2FZ1835DLWS-10 |
Locating Pin | - | 2FZ1835DLWS-06 |
O Ring | 31.5×3.55 | 31.5×3.55 |
Parts list of Hinge structure
Description | FZ2821LWS Part No./Model | FZ2835LWS Part No./Model |
Plug NPT1/2 | SFZ2835-39 | SFZ2835-39 |
Hinge Pin | 2FZ2821DLWS-08 | 2FZ2835ALWS-08 |
Hinge Bracket | 2FZ2821DLWS-06 | 2FZ2835ALWS-06 |
Locating Pin | 2FZ2821DLWS-07 | 2FZ2835ALWS-07 |
O Ring | 31.5×3.55 | 38.7×3.55 |
FZ1821LWS/FZ1835LWS Parts List
Description | FZ1821LWS/FZ1835LWS Part No./Model |
Body | 1 |
Ram Assembly | 2FZ1835DLWS.02（）-00 |
Door bolt | 2FZ1835DLWS-09 |
Plug NPT1/2 | JB/ZQ4447-1997 |
Hinge Pin | 2FZ1835DLWS-07 |
O-ring | 31.5×3.55 |
Dowel Pin | 2FZ1835DLWS-06 |
grease fitting | N/A |
Dowel Pin | GB/T120.1-2000 12×30-A |
Socket cap screw | ANSI B18.3-1982 1/2"-13UNC-2A×3.25" |
Plug | JB/ZQ4447-1997 NPT3/4 |
Socket cap screw | ANSI B18.3-1982 1/2"-13UNC-2A×1.5" |
Left Hinge Bracket | 2FZ1835DLWS-05 |
Right Hinge Bracket | 2FZ1835DLWS-10 |
O-ring | 19×3.55 |
Straight oil pipe | 2FZ1835DLWS-04 |
Bent oil pipe | N/A |
Right Cylinder head | 2FZ1835DLWS.03.08-00 |
Left Cylinder head | 2FZ1835DLWS.08.02-00 |
O-ring | 175×3.55 |
Locking Shaft Seal Assembly | See3.2.4 |
Hydraulic cylinder | 2FZ1835DLWS.03-03 |
Socket cap screw | ANSI B18.3-1982 5/16"-18UNC-2A×0.75" |
Gasket | N/A |
Support ring | 2FZ1835DLWS.03-05 |
Piston lock nut | 2FZ1835DLWS.03-07 |
Piston | 2FZ1835DLWS.03-06 |
O-ring | 73×5.3 |
Piston Seal | 2FZ2821DLWS.03-05 |
Secondary Seal System | N/A |
Ram Shaft Seal Assembly | See3.2.2 |
Ram shaft | 2FZ1835DLWS.03-16 |
O-ring | 290×7 |
Right door | 2FZ1835DLWS.03-01 |
Left door | 2FZ1835DLWS.08-01 |
Screw | 2FZ1835DLWS.03-14 |
O-ring | 22.4×3.55 |
Cylinder.manifold A | 2FZ1835DLWS.03-04 |
Locking screw | 2FZ1835DLWS.03-10 |
Cylinder Bolt | 2FZ1835DLWS.03-11 |
Cap Nut | 2FZ1835DLWS.03-12 |
FZ2821LWS Parts list
Description | FZ2821LWS Part No./Model |
Body | 1 |
Ram Assembly | 2FZ2821DLWS.02（）-00 |
Door bolt | 2FZ2821DLWS-11 |
Plug NPT1/2 | SFZ2835-39 |
Hinge Pin | 2FZ2821DLWS-08 |
O-ring | 31.5×3.55 |
Dowel Pin | 2FZ2821DLWS-07 |
grease fitting | GB1152 M10×1 |
Dowel Pin | GB/T116-86 A12×40 |
Socket cap screw | N/A |
Plug NPT 1" | F02-15 |
Socket cap screw | 2FZ2821DLWS-12 |
Hinge Bracket | 2FZ2821DLWS-06 |
O-ring | 19×3.55 |
Straight oil pipe | 2FZ2821DLWS-04 |
Bent oil pipe | 2FZ2821DLWS-05 |
Right Cylinder head | 2FZ2821DLWS.03.11-00 |
Left Cylinder head | 2FZ2821DLWS.09.03-00 |
O-ring | 175×3.55 |
Locking Shaft Seal Assembly | See3.2.4 |
Right Hydraulic cylinder | 2FZ2821DLWS.03-03 |
Left Hydraulic cylinder | 2FZ2821DLWS.09-02 |
Socket cap screw | 2FZ2821DLWS.03-07 |
Gasket | N/A |
Support ring | 2FZ2821DLWS.03-08 |
Piston lock nut | 2FZ2821DLWS.03-14 |
Piston | 2FZ2821DLWS.03-06 |
O-ring | 63×5.3 |
Piston Seal | 2FZ2821DLWS.03-05 |
Secondary Seal System | N/A |
Ram Shaft Seal Assembly | See3.2.2 |
Ram shaft | 2FZ2821DLWS.03-04 |
O-ring | 350×7 |
Right door | 2FZ2821DLWS.03-01 |
Left door | 2FZ2821DLWS.09-01 |
Screw | GB80 M8×12 |
O-ring | 23.6×3.55 |
Cylinder.manifold A | N/A |
Locking screw | 2FZ2821DLWS.03-12 |
Cylinder Bolt | 2FZ2821DLWS.03-09 |
Cap Nut | 2FZ2821DLWS.03-10 |
FZ2835LWS Parts list
Description | FZ2835LWS Part No./Model | |
Body | 1 | |
Ram Assembly | 2FZ2835ALWS.02（）-00 | |
Door bolt | 2FZ2835ALWS-10 | |
Plug NPT1/2 | SFZ2835-39 | |
Hinge Pin | 2FZ2835ALWS-08 | |
O-ring | 38.7×3.55 | |
Dowel Pin | 2FZ2835ALWS-07 | |
grease fitting | GB1152 M10×1 | |
Dowel Pin | GB120 A16×65 | |
Socket cap screw | N/A | |
Plug NPT 1" | SFZ2835-38 | |
Socket cap screw | 2FZ2835ALWS-11 | |
Hinge Bracket | 2FZ2835ALWS-06 | |
O-ring | 22.4×3.55 | |
Straight oil pipe | 2FZ2835ALWS-04 | |
Bent oil pipe (1) | 2FZ2835ALWS-05 | |
Bent oil pipe(2) | 2FZ2835ALWS-02 | |
Right Cylinder head | 2FZ2835ALWS.03-12 | |
Left Cylinder head | 2FZ2835ALWS.09-12 | |
O-ring | 230×7 | |
Locking Shaft Seal Assembly | See3.2.4 | |
Hydraulic cylinder | 2FZ2835ALWS.03-04 | |
Socket cap screw | 2FZ2835ALWS.03.08 | |
Gasket | GB93 10 | |
Support ring | 2FZ2835ALWS.03.09 | |
Piston lock nut | 2FZ2835ALWS.03-16 | |
Piston | 2FZ2835ALWS.03-07 | |
O-ring | 75×5.3 | |
Piston Seal | 2FZ2835ALWS.03-06 | |
Secondary Seal System | See 3.2.3 | |
Ram Shaft Seal Assembly | See3.2.2 | |
Ram shaft | 2FZ2835ALWS.03-05 | |
O-ring | 400×7 | |
Right door | 2FZ2835ALWS.03.01-00 | |
Left door | 2FZ2835ALWS.09.01-00 | |
Screw | 2FZ2835ALWS.03.15 | |
O-ring | 25×3.55 | |
Cylinder.manifold A | N/A | |
Locking screw | 2FZ2835ALWS.03.13 | |
Cylinder Bolt | 2FZ2835ALWS.03-10 | |
Cap Nut | 2FZ2835ALWS.03-11 |
FZ1821LWS /FZ1835LWS Spare Parts
Description | FZ1821LWS /FZ1835LWS Part No./Model |
O-ring | 31.5×3.55 |
O-ring | 19×3.55 |
O-ring | 175×3.55 |
O-ring | 36.5×5.3 |
O-ring | 71×3.55 |
Wiper ring | 2FZ1835DLWS.03.09-01 |
O-ring | 73×5.3 |
Piston Seal | 2FZ2821DLWS.03-05 |
Wiper ring | 2FZ1835DLWS.03.02-01 |
O-ring | 90×5.3 |
O-ring | 75×5.3 |
O-ring | 290×7 |
O-ring | 22.4×3.55 |
FZ2821LWS Spare Parts for one year
Description | FZ2821LWS Part No./Model |
O-ring | 31.5×3.55 |
O-ring | 19×3.55 |
O-ring | 175×3.55 |
O-ring | 2FZ2821DLWS.03.13-04 |
O-ring | 73×3.55 |
Wiper ring | 2FZ2821DLWS.03.13-03 |
O-ring | 63×5.3 |
Piston Seal | 2FZ2821DLWS.03-05 |
Wiper ring | 2FZ2821DLWS.03.02-03 |
O-ring | 92.5×5.3 |
O-ring | 75×5.3 |
O-ring | 350×7 |
O-ring | 23.6×3.55 |
FZ2835LWS Spare Parts
Description | FZ2821LWS Part No./Model |
O-ring | 38.7×3.55 |
O-ring | 22.4×3.55 |
O-ring | 230×7 |
Packing | 2FZ2835ALWS.03.14.03-00 |
Wiper ring | 2FZ2835ALWS.03.14-05 |
O-ring | 75×5.3 |
Piston Seal | 2FZ2835ALWS.03-06 |
Secondary sealing grease | 2 |
Wiper ring | 2FZ2835ALWS.03.02-03 |
Piston Seal | 2FZ2835ALWS.03.02.04-00 |
Lipring (cover) | 2FZ2835ALWS.03.02-06 |
O-ring | 400×7 |
O-ring | 25×3.55 |
2. On-Site Fault Repair Cases
Case 1: 2FZ1835LWS BOP Ram Shaft Leakage
Scenario: Leakage occurred at the ram shaft seal during drilling, reducing wellbore pressure control efficiency. Root Cause: Worn wiper rings (P/N: 2FZ1835DLWS.03.02-01) and hardened O-rings (90×5.3) due to prolonged exposure to high-temperature formation fluids, violating GB/T 3452.1-2005 seal standards. Repair: Replaced wiper rings and O-rings with annual spares, cleaned the ram shaft surface to remove debris, and applied high-temperature grease. Prevention: Shorten seal replacement cycle to 8 months in high-temperature wells; install a fluid cooler to reduce operating temperature.
Case 2: 2FZ2821LWS BOP Locking Shaft Seizure
Scenario: The locking shaft failed to actuate, preventing ram locking after closure. Root Cause: Corrosion and debris accumulation on the support ring (P/N: 2FZ2821DLWS.03.13-02) and wiper ring, caused by inadequate lubrication and saltwater intrusion. Repair: Disassembled the locking shaft seal assembly, cleaned components with degreaser, replaced corroded parts, and applied anti-seize lubricant compatible with saltwater.Prevention: Lubricate locking shafts bi-weekly in offshore environments; flush with fresh water after each operation to remove salt residues.
Case 3: FZ2835LWS BOP Piston Seal Failure
Scenario: Hydraulic cylinder failed to close the ram completely, resulting in incomplete wellbore sealing. Root Cause: Damaged piston seals (P/N: 2FZ2835ALWS.03-06) due to overpressure (exceeding 52.5MPa rated hydraulic control pressure) and incompatible hydraulic oil. Repair: Replaced piston seals and hydraulic oil with ISO VG 46 grade (compliant with API 670), adjusted hydraulic system pressure to 21MPa (recommended operation pressure). Prevention: Install pressure relief valves to avoid overpressure; regularly test hydraulic oil purity and replace every 6 months.
Case 4: 2FZ2835LWS BOP Secondary Seal System Blockage
Scenario: Secondary seal grease failed to inject, losing backup sealing capacity. Root Cause: Blockage in the cock (P/N: 2FZ2835ALWS.03-03) due to dried grease and杂质 accumulation. Repair: Disassembled the cock, cleared blockages with a high-pressure air gun, replaced old grease with genuine secondary sealing grease, and tested injection flow. Prevention: Inject fresh grease monthly to keep the system unobstructed; use a filter when refilling grease to remove impurities.
3. FAQ
Question | Answer |
What is the compatibility of pipe ram assemblies across LWS models? | Pipe ram assemblies are model-specific: 2FZ1835DLWS series for 2FZ1821LWS/2FZ1835LWS, 2FZ2821DLWS for 2FZ2821LWS, and 2FZ2835ALWS for 2FZ2835LWS. Do not mix parts across models, as bore size and pressure ratings differ, leading to seal failure. |
Can I use non-genuine O-rings and seals for maintenance? | No. Non-genuine seals may not meet API 16A and GB standards for pressure resistance and chemical compatibility. They can cause leakage, pressure loss, or catastrophic BOP failure. Always use original parts (e.g., O-rings 90×5.3, 75×5.3) to ensure safety. |
What torque specifications apply to M20 cylinder bolts of LWS BOPs? | For M20 cylinder bolts (e.g., 2FZ1835DLWS.03-11), torque to 220-250N·m per GB/T 16823.3-1997. Retorque after the first 100 operating hours and quarterly thereafter to prevent loosening from vibration. |
How to determine if ram rubber seals need replacement? | Replace rubber seals if: ① Wear depth exceeds 0.5mm; ② Cracks or deformation are visible; ③ Hardness exceeds 80 Shore A (test with a durometer); ④ Leakage occurs after ram closure. For high-corrosion wells, replace every 6 months proactively. |
What is the service life of LWS Ram BOP under normal operating conditions? | Under proper maintenance (regular seal replacement, lubrication, and pressure testing), the main body has a service life of 8-10 years. Hydraulic cylinders and seal assemblies typically require replacement every 3-5 years, depending on operation frequency and environmental conditions. |
4. Procurement Guidance & Call to Action
The LWS Series Ram BOPs and their spare parts are engineered to meet the strictest well control standards (API 16A, GB/T 3452.1-2005), ensuring reliable performance in high-pressure, corrosive oilfield environments. Our genuine parts—including pipe ram assemblies, seal systems, hydraulic components, and annual spare kits—are precision-manufactured to match original equipment specifications, eliminating compatibility risks and minimizing downtime.
We provide personalized support, including part compatibility verification, maintenance consulting, and on-site technical guidance to optimize your LWS BOP operation. The annual spare kits are pre-configured with high-wear parts (O-rings, wiper rings, piston seals) to align with maintenance schedules, ensuring you have critical components on hand when needed.
Choose genuine LWS Ram BOP parts and assemblies to safeguard your drilling operations, maintain regulatory compliance, and extend equipment service life. Contact us today to discuss your specific model requirements (FZ18/28 series, single/double ram), spare part needs, or technical support inquiries. Our team will tailor a solution aligned with your operational goals and well control standards.
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Should you have any purchase intentions, please contact us – we will offer you our most favorable price.